# برنامج تدريبى مجانى داخل المنتدى فى هندسة السيارات / جزء (1) (2)



## mohamed abouzahra (6 أغسطس 2007)

_بسم الله الرحمن الرحيم_

_الى كل من يهمة مجال السيارات _

_سوف اقوم ان شاء الله _

_بوضع شرح بعض منظومات السيارات ومبداها _

_يعنى لكى يتم فهم الانظمة لابد من فهم اساسيات الكهرباء والالكترونيات ._

_وربنا يوفقنى فى ذلك._
_ان الله فى عون العبد ما دام العبد فى عون اخيه ._ 




البداية هى مبادى الكهرباء واساسيتها 


سوف نتناول المواضيع التالية ان شاء الله


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Electrical Fundamentals [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Electrical Circuits [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Control Devices[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Circuit Protection [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Variable Resistors[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Understanding Relays [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Battery Basics[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Battery Services[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Understanding Alernators [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Understanding Logic Gates[/SIZE][/FONT] 




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1. 
*Electrical Fundamentals*





[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]MATTER[/SIZE]
*Everything in the world is made of matter. Matter is anything that has mass (weight) and occupies space. [/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]Matter can be made up of a group or series of different atoms to form a molecule. These groups of atoms (molecules) are sometimes called compounds. Some types of matter can be broken down to a single atom while still maintaining the properties of the original material. These types of material are called elements.[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]Matter has three states: Solid, Liquid, and Vapor.[/FONT]








[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
MOLECULE EXAMPLE
*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]Imagine a lake. Now imagine taking the smallest particle or piece of water from the lake. You would have a single molecule of water, *H2O,* which is made up of two hydrogen atoms and one oxygen atom.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Not all materials are made up of molecules. Copper, for example, is made up of a single copper atom. These are called elements. Each element is a type of matter that has certain individual characteristics.[/SIZE][/FONT]










[FONT=Verdana, Arial, Helvetica]
[/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]*THE ATOM*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]One of the basic building blocks in the universe for matter is the atom. All matter - gas, liquid, or solid - is made up of molecules or atoms joined together. These atoms are the smallest particle into which an element or substance can be divided without losing its property.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]A single atom consists of three basic components: a proton, a neutron, and an electron. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Within the atom there is a Nucleus. The Nucleus contains the protons and neutrons. Orbiting around the nucleus are the electrons.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]An atom is similar to a miniature solar system. As with the sun in the center of the universe, the nucleus is in the center of the atom. Protons and Neutrons are contained inside the nucleus. Orbiting around the nucleus are the electrons.[/SIZE][/FONT]










[FONT=Verdana, Arial, Helvetica]
[/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]*ATOM CONSTRUCTION
*An atom is similar to a miniature solar system. As the sun is in the center of the solar system, so is the nucleus is in the center of the atom. Protons and neutrons are contained within the nucleus. Electrons orbit around the nucleus, which would be similar to planets orbiting around the sun. [/SIZE][/FONT]

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[/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]*NUCLEUS
*The Nucleus is located in the center of the atom (shown in red).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]The Nucleus contains the protons and neutrons. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Orbiting around the nucleus are the electrons.[/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
PROTONS
*Protons are located within the nucleus of the atom (shown in blue).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Protons are positively (+) charged.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]
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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*NEUTRONS
*Neutrons add atomic weight to an atom (shown in green).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Neutrons have no electrical charge.[/SIZE][/FONT]


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## mohamed abouzahra (6 أغسطس 2007)

نكمل الموضوع .





[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
ELECTRONS
*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]Electrons orbit around the nucleus of the atom (shown in yellow).[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Electrons are negatively (-) charged.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Since electrons are lighter than protons and are outside the nucleus, they can be easily moved from atom to atom to form a flow of electrons. Normally electrons are prevented from being pulled into the atom by the forward momentum of their rotation. Electrons are also prevented from flying away because of the magnetic attraction of the protons inside the nucleus, the same type of force that keeps the planets orbiting around the sun.[/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*ELECTRICAL CHARGES 
*Opposite electrical charges always attract each other. So these particles with opposite charges will tend to move toward each other. Like electrical charges always repel. So particles with like charges will move away from each other.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Remember: Opposites charges attract, and like charges repel.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Atoms always try to remain electrically balanced.[/SIZE][/FONT]









[FONT=Verdana, Arial, Helvetica][SIZE=-1]*BALANCED ATOMS
*Atoms normally have an equal number of electrons and protons. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]Atoms have no electrical charge. They are neither positive nor negative. They are electrically neutral or BALANCED.The negative charge of the electrons will cancel the positive charge of the protons, thus balancing the charge of the atom.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]This cancellation of charges creates a natural attraction or bonding between the positive proton and the negative electron. [/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
ION PARTICLES
*When an atom loses or gains an electron, an imbalance occurs. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]The atom becomes either a positively or negatively charged particle called an ION. These unbalanced charged ION particles are responsible for electron flow (electricity).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]IONs will take or release an electron to become balanced again.[/SIZE][/FONT]









[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
ION CHARGE
*A positive (+) ION has one less electron than it has protons.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]A negative (-) ION has one more electron than it has protons.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]The positive ION attracts a negative ION to become balanced. This attraction or difference in electrical potential causes electron flow.[/SIZE][/FONT]








[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
ELECTRON ORBITS
*Electrons rotate around the atom at different orbits called Rings, Orbits, or Shells.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]BOUND ELECTRONS orbit the nucleus on the inner rings. Bound electrons have a strong magnetic attraction to the nucleus.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]FREE ELECTRONS orbit on the outermost ring which is known as the VALANCE RING. [/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
FREE ELECTRONS
*Only the FREE ELECTRONS in the outermost shell (Valance Ring) are free to move from atom to atom. This movement is called ELECTRON FLOW.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]These FREE ELECTRONS are loosely held and can easily be moved to another atom or ion. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Because of their distance from the nucleus, free electrons have a weak magnetic attraction. Since this attraction is not as strong to the nucleus as the bound electrons on the inner orbits, the electrons move easily from atom to atom.[/SIZE][/FONT] 








[FONT=Verdana, Arial, Helvetica][SIZE=-1]*INSULATORS
*An INSULATOR is any material that inhibits (stops) the flow of electrons (electricity).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]An insulator is any material with 5 to 8 free electrons in the outer ring.Because, atoms with 5 to 8 electrons in the outer ring are held (bound) tightly to the atom, they CANNOT be easily moved to another atom nor make room for more electrons.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Insulator material includes glass, rubber, and plastic.[/SIZE][/FONT]


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## mohamed abouzahra (6 أغسطس 2007)

ونكمل





[FONT=Verdana, Arial, Helvetica][SIZE=-1]*CONDUCTORS
*A CONDUCTOR is any material that easily allows electrons (electricity) to flow.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]A CONDUCTOR has 1 to 3 free electrons in the outer ring.Because atoms with 1 to 3 electrons in the outer ring are held (bound) loosely to the atom, they can easily move to another atom or make room for more electrons.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Conductor material includes copper and gold.[/SIZE][/FONT]










[FONT=Verdana, Arial, Helvetica][SIZE=-1]*SEMICONDUCTORS
*Any material with exactly 4 free flectrons in the outer orbit are called SEMICONDUCTORS.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]A semiconductor is neither a conductor or insulator.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]semiconductor material includes carbon, silicon, and germanium.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]These materials are be used in the manufacturer of diodes, transistors, and integrated circuit chips.[/SIZE][/FONT]






[FONT=Verdana, Arial, Helvetica][SIZE=-1]Two Current Flow theories exist. The first is:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*ELECTRON THEORY*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]
[SIZE=-1]The Electron Theory states that current flows from NEGATIVE to POSITIVE. Electrons move from atom to atom as they move through the conductor towards positive.[/SIZE]

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[FONT=Verdana, Arial, Helvetica][SIZE=-1]The second Current Flow theory is:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*CONVENTIONAL THEORY*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]
[SIZE=-1]Conventional theory, also known as HOLE THEORY, states that current flows from POSITIVE to NEGATIVE. Protons or the lack of electrons (the holes) move towards the negative. (Current flow direction in Hole Theory is the opposite of that in Electron Theory.)[/SIZE]
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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*VOLTAGE*
Voltage is the electrical force that moves electrons through a conductor. Voltage is electrical pressure also known as EMF (Electro Motive Force) that pushes electrons.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]The greater the difference in electrical potential push (difference between positive and negative), the greater the voltage force potential.

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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*
MEASUREMENT*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]A VOLTMETER measures the voltage potential across or parallel to the circuit. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]The Voltmeter measures the amount of electrical pressure difference between two points being measured.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Voltage can exist between two points without electron flow.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2] [/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica][SIZE=-1]*VOLTAGE UNITS
*Voltage is measured in units called VOLTS. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Voltage measurements can use different value prefixes such as millivolt, volt, Kilovolt, and Megavolt.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

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[FONT=Verdana, Arial, Helvetica][SIZE=-2]VOLTAGE[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]LESS THAN
BASE UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]BASIC UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]LARGER THAN
BASE UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Symbol[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]mV[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]V[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]kV[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Pronounced[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]millivolt[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Volt[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Kilovolt[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Multiplier[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]0.001[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]1[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]1,000[/SIZE][/FONT] 






[FONT=Verdana, Arial, Helvetica][SIZE=-1]*CURRENT (AMPERES)*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]CURRENT is the quantity or flow rate of electrons moving past a point within one second. Current flow is also known as amperage, or amps for short.[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Higher voltage will produce higher current flow, and lower voltage will produce lower current flow.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

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## mohamed abouzahra (6 أغسطس 2007)

ونكمل الموضوع 




[FONT=Verdana, Arial, Helvetica][SIZE=-1]*MEASUREMENT
*An AMMETER measures the quantity of current flow.[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Ammeters are placed in series (inline) to count the electrons passing through it.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Example: A water meter counts the gallons of water flowing through it.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

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[SIZE=-1][FONT=Verdana, Arial, Helvetica][SIZE=-1]*AMPERAGE UNITS
*Current flow is measured in units called Amperes or AMPS.[/SIZE]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Amperage measurements can use different value prefixes, such as microamp, milliamp, and Amp.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

[/SIZE][/FONT]
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[FONT=Verdana, Arial, Helvetica][SIZE=-2][FONT=Verdana, Arial, Helvetica][SIZE=-2]AMPERAGE[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]LESS THAN
BASE UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]LESS THAN
BASE UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]BASIC UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]Symbol[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]µA[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]mA[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]A[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]Pronounced[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]Microamp[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]milliamp[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]Amp[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]Multiplier[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]0.000001[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]0.001[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-2]1[/SIZE][/FONT] [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1][/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica][SIZE=-1]*AFFECTS OF CURRENT FLOW
*Two common effects of current flow are Heat Generation and Electromagnetism.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]HEAT: When current flows, heat will be generated. The higher the current flow the greater the heat generated. An example would be a light bulb. If enough current flows across the filament, it will glow white hot and illuminate to produce light.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]ELECTROMAGNETISM: When current flows, a small magnetic field is created. The higher the current flow, the stronger the magnetic field. An example: Electromagnetism principles are used in alternators, ignition systems, and other electronic devices.[/SIZE][/FONT]





[FONT=Verdana, Arial, Helvetica][SIZE=-1]*RESISTANCE
*Resistance is the force that reduces or stops the flow of electrons. It opposes voltage.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Higher resistance will decrease the flow of electrons and lower resistance will allow more electrons to flow.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

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[FONT=Verdana, Arial, Helvetica][SIZE=-1]*MEASUREMENT
*An OHMMETER measures the resistance of an electrical circuit or component. No voltage can be applied while the ohmmeter is connected, or damage to the meter will occur.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Example: Water flows through a garden hose, and someone steps on the hose. The greater the pressure placed on the hose, the greater the hose restriction and the less water flows.[/SIZE][/FONT]





[FONT=Verdana, Arial, Helvetica][SIZE=-1]*RESISTANCE UNITS
*Resistance is measured in units called OHMS.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Resistance measurements can use different value prefixes, such as Kilo ohm and Megaohms.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

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[FONT=Verdana, Arial, Helvetica][SIZE=-2][FONT=Verdana, Arial, Helvetica][SIZE=-1]AMPERAGE[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]BASIC UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]MORE THAN
BASE UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]MORE THAN
BASE UNIT[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Symbol[/SIZE][/FONT] [SIZE=-1][/SIZE]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]K[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]M[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Pronounced[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Ohm[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Kilo ohm[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Megaohm[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]Multiplier[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]1[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]1,000[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica][SIZE=-1]1,000,000[/SIZE][/FONT] [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1][/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica][SIZE=-1]*RESISTANCE FACTORS*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]Various factors can affect the resistance. These include:[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]LENGTH of the conductor. The longer the conductor, the higher the resistance.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]DIAMETER of the conductor. The narrower the conductor, the higher the resistance.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]TEMPERATURE of the material. Depending on the material, most will increase resistance as temperature increases.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]PHYSICAL CONDITION (DAMAGE) to the material. Any damage will increase resistance.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]TYPE of MATERIAL used. Various materials have a wide range of resistances.[/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica][SIZE=-1]*TYPES OF ELECTRICITY*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]
[SIZE=-1]Two basic types of Electricity classifications:[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*STATIC ELECTRICITY* is electricity that is standing still. Voltage potential with *NO* electron flow.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-2]*[SIZE=-1]DYNAMIC ELECTRICITY[/SIZE]*[SIZE=-1] is electricity that is in motion. Voltage potential *WITH* electron flow. Two types of D[/SIZE][/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]ynamic electricity exist: [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*Direct Current (DC)* Electron Flow is in only one direction.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*Alternating Current (AC)* Electron flow alternates and flows in both directions (back and forth).[/SIZE][/FONT]





[FONT=Verdana, Arial, Helvetica][SIZE=-1]*STATIC ELECTRICITY*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]
[SIZE=-1]Voltage potential with *NO* electron flow.[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Example: By rubbing a silk cloth on a glass rod, you physically remove electrons from the glass rod and place them on the cloth. The cloth now has a surplus of electrons (negatively charged), and the rod now has a deficiency of electrons (positively charged). [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Another example: Rub your shoes on a rug and then touch a metal table or chair .... [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]Zap!! [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]The shock you felt was the static electricity dissipating through your body.[/SIZE][/FONT]















[FONT=Verdana, Arial, Helvetica][SIZE=-1]*DYNAMIC ELECTRICITY*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]is electricity in motion, meaning you have electrons flowing, in other words voltage potential WITH electron flow.[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Two types of dynamic electricity exists: [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Direct Current (DC)[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Alternating Current (AC[/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica][SIZE=-1]*DIRECT CURRENT (DC)*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]Electricity with electrons flowing in only one direction is called Direct Current or DC. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]DC electrical systems are used in cars.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

[/SIZE][/FONT]












[FONT=Verdana, Arial, Helvetica][SIZE=-1]*ALTERNATING CURRENT (AC)*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2][SIZE=-1]Electricity with electrons flowing back and forth, negative - positive- negative, is called Alternating Current, or AC. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]The electrical appliances in your home use AC power.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-2]

[/SIZE][/FONT]










[FONT=Verdana, Arial, Helvetica][SIZE=-1]*SOURCES OF ELECTRICITY
*Electricity can be created by several means: Friction, Heat, Light, Pressure, Chemical Action, or Magnetic Action.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Only a few of these sources of energy are used in the automobile. The battery produces electricity through chemical action, and the alternator produces electricity through magnetic action.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*Friction* creates static electricity.
*Heat* can act upon a device called a thermo couple to create DC.
*Light *applied to photoelectric materials will produce DC electricity.
*Pressure* applied to a piezoelectric material will produce DC electricity.
*Chemical Action* of certain chemicals will create electricity.[/SIZE][/FONT]


وفى نهاية الموضوع وليس نهاية المواضيع هناك اخرى الكثير ان شاء الله وربنا يوفقنى فى ذلك ان شاء الله ​


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## mohamed abouzahra (6 أغسطس 2007)

الخلاصة من هذا الموضوع 

هو التعرف على بعض المفاهيم مثل 
ما معنى مادة موصلة او شبة موصلة او معرزولة 

وايضا ما معنى فولت وامبير اسيبكم تشوفو الموضوع احسن .


اخوكم / محمد أبوزهرة .


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## م. محمد عبد الحميد (6 أغسطس 2007)

واصل يا اخي 
الله يبارك فيك


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## mohamed abouzahra (6 أغسطس 2007)

الموضوع الثانى .

*Electrical Circuits*


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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*AN ELECTRICAL CIRCUIT
*The circuit shown below has a power source, fuse, switch, two lamps and wires connecting each into a loop or circle. When the connection is complete, current flows from the positive terminal of the battery through the wire, the fuse, the switch, another wire, the lamps, a wire and to the negative terminal of the battery. The route along which the electricity flows is called an electrical circuit.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]



[/FONT]

​[FONT=Verdana, Arial, Helvetica][SIZE=-1]*ELECTRICAL CIRCUIT REQUIREMENTS
*A complete Electrical Circuit is required in order to make electricity practical. Electrons must flow from and return to the power source.[/SIZE][/FONT] 
[FONT=Verdana, Arial, Helvetica][SIZE=-1]There are three different [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]circuit types[/SIZE][/FONT][SIZE=-1],[FONT=Verdana, Arial, Helvetica] all require the same basic components: [/FONT][/SIZE]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]1. Power Source is needed to supply the flow of electrons (electricity).
2. Protection Device prevents damage to the circuit in the event of a short. 
3. Load Device converts the electricity into work.
4. Control Device allows the user control to turn the circuit on or off
5. Conductors provide an electrical path to and from the power source.[/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica][SIZE=-1]*BASIC CIRCUIT CONSTRUCTION
*1. Power Source (Battery, Alternator, Generator, etc.)
2. Protection Device (Fuse, Fusible Link, or Circuit Breaker)
3. Load Device (Lamp, Motor, Winding, Resistor, etc.
4. Control (Switch, Relay, or Transistor)
5. Conductors (A Return Path, Wiring to Ground)[/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*LOADS*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]The illustration below has a horn in place of the lamp. Any device such as a lamp, horn, wiper motor, or rear window defogger, that consumes electricity is called a load. In an electrical circuit, all loads are regarded as resistance. Loads use up voltage and control the amount of current flowing in a circuit. Loads with high resistance cause less current to flow while those with lower resistance allow high current rates to flow.[/SIZE][/SIZE][/FONT] 





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]AUTOMOTIVE ELECTRICAL CIRCUITS[/SIZE]
*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In an automotive electrical circuit, one end of the wire from each load returning to the battery is connected to the vehicle body or frame. Therefore, the vehicle body or frame itself functions as a conductor, allowing current to flow though the body or frame and back to the battery. The body or frame is then referred to as the body ground (or earth) of the circuit (meaning that part of the circuit that returns the current to the battery). [/SIZE][/FONT]






​[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]W[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]HAT IS OHM'S LAW?[/FONT]*[/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif]
[SIZE=-1]A simple relationship exists between voltage, current, and resistance in electrical circuits. Understanding this relationship is important for fast, accurate electrical problem diagnosis and repair. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*OHM'S LAW*[/SIZE][SIZE=-2]
[SIZE=-1]Ohm's Law says: The current in a circuit is directly proportional to the applied voltage and inversely proportional to the amount of resistance. This means that if the voltage goes up, the current flow will go up, and vice versa. Also, as the resistance goes up, the current goes down, and vice versa. Ohm's Law can be put to good use in electrical troubleshooting. But calculating precise values for voltage, current, and resistance is not always practical ... nor, really needed. A more practical, less time-consuming use of Ohm's Law would be to simply apply the concepts involved:[/SIZE] [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]SOURCE VOLTAGE[/SIZE]*[SIZE=-1] is not affected by either current or resistance. It is either too low, normal, or too high. If it is too low, current will be low. If it is normal, current will be high if resistance is low, or current will be low if resistance is high. If voltage is too high, current will be high[/SIZE]. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CURRENT[/SIZE]*[SIZE=-1] is affected by either voltage or resistance. If the voltage is high or the resistance is low, current will be high. If the voltage is low or the resistance is high, current will be low. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RESISTANCE* is not affected by either voltage or current. It is either too low, okay, or too high. If resistance is too low, current will be high at any voltage. If resistance is too high, current will be low if voltage is okay. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*NOTE:* When the voltage stays the same, such as in an Automotive Circuit... current goes up as resistance goes down, and current goes down as resistance goes up. Bypassed devices reduce resistance, causing high current. Loose connections increase resistance, causing low current. [/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]OHM'S LAW FORMULA[/SIZE]*
[SIZE=-1]When voltage is applied to an electrical circuit, current flows in the circuit. The following special relationship exists among the voltage, current and resistance within the circuit: the size of the current that flows in a circuit varies in proportion to the voltage which is applied to the circuit, and in inverse proportion to the resistance through which it must pass. This relationship is called Ohm's law, and can be expressed as follows:[/SIZE][/SIZE][/FONT]​[SIZE=+2]*E = I R*[/SIZE]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Voltage = Current x Resistance[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]E [/SIZE]*[SIZE=-1]Voltage applied to the circuit, in volts (*V*) [/SIZE][/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*I *Current flowing in the circuit, in amperes (*A*) [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*R* Resistance in the circuit, in ohms[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In practical terms "V = I x R" which means 
"Voltage = Current x Resistance". [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1 volt will push one amp through 1 ohm of resistance.[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*NOTE:* E = IR, V=AR, or V=IR are all variations of the same formula. How you learned Ohm's law will determine which one you will use. Personal preference is the only difference; anyone will get you the correct answer.[/SIZE][/FONT]
​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]OHM'S LAW SYMBOL SHORTCUT[/SIZE]*
[SIZE=-1]Mathematical formulas can be difficult for many who don't use them regularly. Most people can remember a picture easier than a mathematical formula. By using the Ohms law symbol below, anyone can remember the correct formula to use. By knowing any two values you can figure out the third. Simply put your finger over the portion of the symbol you are trying to figure out and you have your formula.[/SIZE][/SIZE][/FONT]


 
​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*APPLICATIONS OF OHM'S LAW*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]
[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]As an application of Ohm's law, any voltage *V*, current *I* or resistance *R* in an electrical circuit can be determined without actually measuring it if the two others values are known. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]This law can be used to determine the amount of current *I* flowing in the circuit when voltage *V* is applied to resistance *R*. As stated previously, Ohm's law is: [/SIZE][/FONT]





[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Current = Voltage / Resistance. [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In the following circuit, assume that resistance R is 2 and voltage V that is applied to it is 12 V. Then, current I flowing in the circuit can be determined as follows: [/SIZE][/FONT]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]This law can also be used to determine the voltage V that is needed to permit current I to pass through resistance R: V = I x R (Voltage= Current x Resistance).
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In the following circuit, assume that resistance R is 4 ohms. The voltage V that is necessary to permit a current I of 3 A to pass through the resistance can be determined as follows: [/SIZE][/FONT]





​[/SIZE][/FONT]
​


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## mohamed abouzahra (6 أغسطس 2007)

ونكمل الموضوع ان شاء الله .

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Still another application of the law can be used to determine the resistance R when the voltage V which is applied to the circuit and current I flowing in the circuit are already known: [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In the following circuit, assume that a voltage V of 12 V is applied to the circuit and current I of 4 A flows in it. Then, the resistance value R of the resistance or load can be determined as follows: [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*TYPES OF CIRCUITS *[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Individual electrical circuits normally combine one or more resistance or load devices. The design of the automotive electrical circuit will determine which type of circuit is used. There are three basic types of circuits:[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]Series Circuit [/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Parallel Circuit*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Series-Parallel Circuit *[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica][SIZE=-1]*SERIES CIRCUITS*[/SIZE][/FONT][SIZE=-2]
[SIZE=-1]A series circuit is the simplest circuit. The conductors, control and protection devices, loads, and power source are connected with only one path to ground for current flow. The resistance of each device can be different. The same amount of current will flow through each. The voltage across each will be different. If the path is broken, no current flows and no part of the circuit works. Christmas tree lights are a good example; when one light goes out the entire string stops working.[/SIZE][/SIZE] 
[SIZE=-2]
[/SIZE]
[SIZE=-2]



[/SIZE]



​[FONT=Verdana, Arial, Helvetica][SIZE=-1]*SERIES CIRCUITS
*A Series Circuit has only one path to ground, so electrons must go through each component to get back to ground. All loads are placed in series. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]Therefore:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]1. An open in the circuit will disable the entire circuit. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]2. The voltage divides (shared) between the loads.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]3. The current flow is the same throughout the circuit.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]4. The resistance of each load can be different.[/SIZE][/FONT]








​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SERIES CIRCUIT CALCULATIONS*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]If, for example, two or more lamps (resistances R1 and R2, etc.) are connected in a circuit as follows, there is only one route that the current can take. This type of connection is called a series connection. The value of current I is always the same at any point in a series circuit[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]. [/SIZE][/FONT]​



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The combined resistance RO in this circuit is equal to the sum of individual resistance R1 and R2. In other words: The total resistance(RO) is equal to the sum of all resistances (R1 + R2 + R3 + .......)[/SIZE][/FONT]




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Therefore, the strength of current (I) flowing in the circuit can be found as follows: [/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Resistance R0 (a combination of resistances R1 and R2, which are connected in series in the circuit as illustrated) and current I flowing in this circuit can be determined as follows: [/SIZE][/FONT]​






​
[SIZE=-1]*Electrical Circuits*
[SIZE=-1]18 of 31[/SIZE] 




​[/SIZE][SIZE=+2][/SIZE]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]VOLTAGE DROP[/SIZE]*
[SIZE=-1]A voltage drop is the amount of voltage or electrical pressure that is used or given up as electrons pass through a resistance (load). All voltage will be used up in the circuit. The sum of the voltage drops will equal source voltage. A voltage drop measurement is done by measuring the voltage before entering the load and the voltage as it leaves the load. The difference between these two voltage readings is the voltage drop.[/SIZE][/SIZE][/FONT]​



​​

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]VOLTAGE DROP TOTAL[/SIZE]*
[SIZE=-1]When more than one load exists in a circuit, the voltage divides and will be shared among the loads. The sum of the voltage drops equal source voltage. The higher the resistance the higher the voltage drop. Depending on the resistance, each load will have a different voltage drop. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]0V + 5V + 7V + 0V = 12V[/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]VOLTAGE DROP CALCULATION[/SIZE]*
[SIZE=-1]When current flows in a circuit, the presence of a resistance in that circuit will cause the voltage to fall or drop as it passes through the resistance. The resultant difference in the voltage on each side of the resistance is called a voltage drop. When current (*I*) flows in the following circuit, voltage drops V1 and V2 across resistances R1 and R2 can be determined as follows from Ohm's law. (The value of current *I* is the same for both R1 and R2 since they are connected in series.)[/SIZE][/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]







[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The sum of the voltage drops across all resistances is equal to the voltage of the power source (VT):[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]




[/SIZE][/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The voltage drop across resistances R1 and R2 in the following circuit can be determined as follows: [/SIZE][/FONT]​



​​ 

PARALLEL CIRCUIT
A parallel circuit has more than one path for current flow. The same voltage is applied across each branch. If the load resistance in each branch is the same, the current in each branch will be the same. If the load resistance in each branch is different, the current in each branch will be different. If one branch is broken, current will continue flowing to the other branches. 




​[FONT=Verdana, Arial, Helvetica][SIZE=-1]*PARALLEL CIRCUITS
*A Parallel Circuit has multiple paths or branches to ground. Therefore:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]1. In the event of an open in the circuit in one of the branches, current will continue to flow through the remaining.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]2. Each branch receives source voltage.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]3. Current flow through each branch can be different.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]4. The resistance of each branch can be different.[/SIZE][/FONT]






​


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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2][SIZE=-1]PARALLEL CIRCUIT[/SIZE]
[SIZE=-1]In parallel connection, two or more resistances (R1, R2, etc.) are connected in a circuit as follows, with one end of each resistance connected to the high (positive) side of the circuit, and one end connected to the low (negative) side. Full battery voltage is applied to all resistances within a circuit having a parallel connection.[/SIZE][/SIZE][/FONT]​




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Resistance R0 (a combination of resistances R1 and R2) in a parallel connection can be determined as follows: [/SIZE][/FONT]​



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]From the above, the total current I flowing in this circuit can be determined from Ohm's law as follows: [/SIZE][/FONT]​



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The total current I is also equal to the sum of currents I1 and I2 flowing through individual resistances R1 and R2 [/SIZE][/FONT]​



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Since battery voltage V is applied equally to all resistances, the strength of currents I1 and I2 can be determined from Ohm's law as follows: [/SIZE][/FONT]​




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Resistance RO (a combination of resistances R1 and R2, which are connected in parallel in the circuit as shown below), the total current I flowing in the circuit, and currents I1 and I2 flowing through resistances R1 and R2, can be determined respectively as follows: [/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]SERIES PARALLEL CIRCUIT[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]A series-parallel circuit has some components in series and others in parallel. The power source and control or protection devices are usually in series; the loads are usually in parallel. The same current flows in the series portion, different currents in the parallel portion. The same voltage is applied to parallel devices, different voltages to series devices. If the series portion is broken, current stops flowing in the entire circuit. If a parallel branch is broken, current continues flowing in the series portion and the remaining branches. [/SIZE][/SIZE][/FONT]








SERIES-PARALLEL CIRCUIT
A resistance and lamps may be connected in a circuit as illustrated below. This type of connecting method is called series-parallel connection, and is a combination of series and parallel connections. The interior dash board lights are a good example. By adjusting the rheostat, you can increase or decrease the brilliance of the lights. 





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The combined resistance R02 in this series-parallel connection can be determined in the following order:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]a. Determine combined resistance R01, which is a combination of resistances R2 and R3 connected in parallel. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]b. Then, determine resistance R02, which is a combination of resistance R1 and combined resistance R01 connected in series. [/SIZE][/FONT]​



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Total current I flowing in the circuit can be determined from Ohm's law as follows: [/SIZE][/FONT]​



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The voltage applied to R2 and R3 can be found by the following formula: [/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Currents I1, I2 and I flowing through resistances R1, R2 and R3 in the series-parallel connection, as shown below, can be determined as follows: [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]



وفى نهاية الموضوع ارجو الدعاء لنا ويجعلة فى ميزان حسناتنا ان شاء الله ​


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## mohamed abouzahra (6 أغسطس 2007)

قريبا الموضوع الثالث ان شاء الله


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## ahmed morshidy (6 أغسطس 2007)

السلام عليكم
ما شاء الله :15: مجهود رائع ومتميز 
كم كنت محتاج الى هذا الجزء من الكهرباء بداية من معنى الفولت voltage
سأكون على متابعة معك باذن الله
جزاك الله خيرا


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## do3a2rose (6 أغسطس 2007)

محمد بجد ماشاء الله عليك 

وانا عارفة انت تعبت اد اية على ماوصلت للموضوع 

وكمان على مانزلته بجد ربنا يبارك فيك


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## الاعرجي (6 أغسطس 2007)

مشكووووووووووور اخي على هذا الموضوع الرائع ونتمنا ان تحضر لنا موضوع عن النضريات في الكهرباء مثل نضرية اوم ودوائر ثفنن ونورتن واكرر الشكر


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## mohamed abouzahra (6 أغسطس 2007)

مشكوررر على هذة الردود 
ان الله فى عون العبد ما دام العبد فى عون اخيه .


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## mohamed abouzahra (6 أغسطس 2007)

بسم الله الرحمن الرحيم 
سوف ابدا الان انشاء الله بوضع الجزء الثالث وهو 
*Control Devices*

وسوف نتكلم فية عن الشوتش وانواعة وكيف يعمل وايضا الريلى ويضا السولنايد ( صمام يعمل بالمجلب المغناطيسى ) 


*Control Devices*
_________________________


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CONTROLS*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Control devices are used to "turn on" or "turn off" current flow in an electrical circuit. Control devices include a variety of switches, relays, and solenoids. *Electronic control devices include* *capacitors, diodes, and transistors, but those will be discussed in another training module*. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Control devices are needed to start, stop, or redirect current flow in an electrical circuit. Most switches require physical movement for operation while relays and solenoids are operated with electromagnetism.[/SIZE][/FONT]


 




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CONTROL DEVICES*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]SWITCHES[/SIZE]*[/SIZE][/FONT] 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Single Pole Single Throw (SPST)
Single Pole Double Throw (SPDT)
Momentary Contact
Multiple Pole Multiple Throw (MPMT or Gang Switch)
Mercury
Temperature (Bimetal)
Time Delay
[/SIZE][/FONT][SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]Flasher
[/FONT][/SIZE]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAYS*[/SIZE][/FONT] 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SOLENOIDS*[/SIZE][/FONT]​ 

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SWITCHES*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A switch is the most common circuit control device. Switches usually have two or more sets of contacts. Opening these contacts is called "break" or "open" the circuit, Closing the contacts is called "make" or "completing" the circuit. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Switches are described by the number of *Poles* and *Throws* they have. "Poles" refer to the number of input circuit terminals while "Throws" refer to the number of output circuit terminal. Switches are referred to as SPST (single-pole, single-throw), SPDT (single-pole, double-throw), or MPMT (multiple-pole, multiple-throw). [/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]SINGLE POLE SINGLE THROW SPST)[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The simplest type of switch is a "hinged pawl" or "knife blade" switch. It either "completes" (turn on) or "break" (turn off) the circuit in a single circuit. This switch has a single input pole and a single output throw.[/SIZE][/FONT]
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[/FONT]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SINGLE POLE DOUBLE THROW SPDT)*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A single-pole input, double-throw output switch has one wire going it and two wires coming out. A Headlamp dimmer switch is a good example of a single-pole double-throw switch. The switch sends current to either the high-beams or low-beams of the headlight circuit. [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif]



[/FONT]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]MULTIPLE POLE MULTIPLE THROW MPMT)[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Multiple-Pole input, Multiple-Throw output switches, which are also known as "gang" switches, have movable contacts in wired in parallel. These switches move together to supply different sets of output contacts with current. An ignition switch is a good example of a multiple-pole multiple-throw switch. Each switch sends current from different source to different output circuits at the same time depending on position. The dotted line between the switches indicates they move together; one will not move without the other moving as well.[/SIZE][/FONT]
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[/FONT]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]MOMENTARY CONTACT[/SIZE]*[SIZE=-1]
The momentary contact switch has a spring-loaded contact that keeps it from making the circuit except when pressure is applied to the button. This is a "*normally open*" type (shown below). A horn switch is a good example of a momentary contact switch. Push the horn button and the hold sounds; release the button and the horn stops. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A variation of this type is the *normally closed* (not shown) which works the opposite as described above*. *The spring holds the contacts closed except when the button is pressed. In other words the circuit is "ON" until the button is pushed to break the circuit.[/SIZE][/FONT]
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[/FONT]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*MERCURY*
A mercury switch is made of a sealed capsule that is partially filled with mercury. In one end of the capsule are two electrical contacts. As the switch is rotated (moved from true vertical) the mercury flows to the opposite end of the capsule with the contacts, completing the circuit. Mercury switches are often be used to detect motion, such as the one used in the engine compartment on the light. Other uses include fuel cut off for roll-overs, and some air bag sensor applications. Mercury is a hazardous waste and should be handled with care.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1] [/SIZE][/FONT]
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[/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BI-METALLIC*
A temperature-sensitive switch, also known as a "bi-metallic" switch, usually contains a bimetal element that bends when heated to make contact completing a circuit or to break contact opening a circuit. In an engine coolant temperature switch, when the coolant reaches the temperature limit, the bimetal element bends causing the contacts in the switch to close. This completes the circuit and lights the warning indicator on the instrument panel. [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif]



[/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*TIME DELAY SWITCH*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The time delay switch contains a bimetal strip, contacts, and a heating element. The time delay switch is normally closed. As current flows through the switch, current flows through the heating element causing it to heat, which causes the bimetal strip to bend and open the contacts. As current continues to flows through the heating element, the bimetal strip is kept hot, keeping the switch contacts open. The amount of time delay before the contacts open is determined by the characteristics of the bimetal strip and the amount of heat produced by the heating element. When power to the switch is turned off, the heating element cools and the bimetal strip returns to the rest position and the contacts are closed. A common application for a time delay switch is the rear window defroster. [/SIZE][/FONT]




​


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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FLASHER
*The flasher operates basically the same as the time delay switch; except when the contacts open, current stops flowing through the heating element. This causes the heating element and bimetal strip to cool. The bimetal strip returns to the rest position which closes the contacts, allowing current to flow through the contacts and heating element again. This cycle repeats over and over until power to the flasher is eliminated. Common uses for this type of switch are the turn signals or the four-way flasher (hazard lamps). [/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAYS*
A relay is simply a remote-control switch, which uses a small amount of current to control a large amount of current. A typical relay has both a *control circuit* and a *power circuit*. Relay construction contains an iron core, electromagnetic coil, and an armature (moveable contact set). There are two types of relays: *normally open* (shown below) and *normally closed* (NOT shown). A Normally open (N.O.) relay has contacts that are "open" until the relay is energized while a normally closed (N.C.) relay has contacts that are "closed" until the relay is energized.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]



[/FONT]



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAY OPERATION*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Current flows through the control coil, which is wrapped around an iron core. The iron core intensifies the magnetic field. The magnetic field attracts the upper contact arm and pulls it down, closing the contacts and allowing power from the power source to go to the load. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]When the coil is not energized, the contacts are open, and no power goes to the load. When the control circuit switch is closed, however, current flows to the relay and energizes the coil. The resulting magnetic field pulls the armature down, closing the contacts and allowing power to the load. Many relays are used for controlling high current in one circuit with low current in another circuit. An example would be a computer, which controls a relay, and the relay controls a higher current circuit. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SOLENOIDS - PULLING TYPE*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A solenoid is an electromagnetic switch that converts current flow into mechanical movement. As current flows through the winding a magnetic field is created. The magnetic field will pull the moveable iron core into the center of the winding. [/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]This type of solenoid is called a "pulling" type solenoid, as the magnetic field pulls the moveable iron core into the coil. [/SIZE][/FONT][SIZE=-1]A common use for pulling solenoids are in the starting system. The starter solenoid engages the starter with the flywheel.[/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SOLENOIDS - PULLING TYPE OPERATION*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]As current flows through the winding a magnetic field is created. These[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]magnetic lines of force want to be as small as possible. If an iron core is placed near the coil that has current flowing through it, the magnetic field will stretch out like a rubber band, reaching out and pulling the iron bar into the center of the coil. [/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SOLENOIDS - PUSH/PULL TYPE*[/SIZE][/FONT][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In a "push-pull" type solenoid, a permanent magnet is used for the core. Since "like" magnetic charges repel and [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2][SIZE=-1]"unlike" magnetic charges attract, by changing the direction of current flow through the coil, the core is either "pulled in" or "pushed out." A common use for this type of solenoid is on electric door locks. [/SIZE][/SIZE][/FONT]









اى استفسار ان شاء الله انا موجود 

ان شاء الله قريبا الموضوع الرابع
​


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## mohamed abouzahra (6 أغسطس 2007)

الموضوع الرابع عن ( حماية الدوائر الكهربية فى السيارات ) 

يارب يعجبكم .


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## mohamed abouzahra (6 أغسطس 2007)

*Circuit Protection*
_______________________________









[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CIRCUIT PROTECTION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Circuit protection devices are used to protect wires and connectors from being damaged by excess current flow caused by either an over current or short-circuit. Excess current causes excess heat, which causes circuit protection to "open circuit". [/SIZE][/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CIRCUIT PROTECTION DEVICES*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Fuses, fuse elements, fusible links, and circuit breakers are used as circuit protection devices. Circuit protection devices are available in a variety of types, shapes, and specific current ratings.[/SIZE][/SIZE][/FONT]​






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSES[/SIZE]*
[SIZE=-1]A fuse is the most common protection device. A fuse is placed in an electrical circuit, so that when current flow exceeds the rating of the fuse it "blows" or "blows out". The element in the fuse melts, opening the circuit and preventing other components of the circuit from being damaged by the overcurrent. The size of the metal fuse element determines its rating. Remember, excessive current causes excess heat, and it's the heat and not the current that causes the circuit protector to open. Once a fuse "blows" it must be replaced with a new one. [/SIZE][/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSE LOCATIONS[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[SIZE=-1]Fuses are located throughout the entire vehicle. Common locations include the engine compartment, behind the left or right kick panels, or under the dash. Fuses are usually grouped together and are often mixed in with other components like relays, circuit breakers, and fuse elements.[/SIZE][/FONT]
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[/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSE BLOCK COVERS[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[SIZE=-1]Fuse / relay block covers usually label the location and position of each fuse, relay, and fuse element contained within.[/SIZE][/FONT]​






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FUSE TYPES*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Fuses are classified into basic categories: blade type fuses or cartridge type fuses. Several variations of each are used.[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]



​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]COMMON FUSE TYPES[/SIZE]*
[SIZE=-1]The blade fuse and fuse element are by far the most commonly used today. Three different types of blade fuses exist; The Maxi Fuse, The Standard Auto fuse, and the Mini fuse. The fuse element has replaced the fusible link and will be explained later.[/SIZE][/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]BASIC CONSTRUCTION[/SIZE]*
[SIZE=-1]The blade type fuse is a compact design with a metal element and transparent insulating housing which is color-coded for each current rating. (Standard Auto shown below; however construction of both the mini and maxi fuses are the same.)[/SIZE][/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FUSE AMPERAGE COLOR RATING
*Fuse amperage color ratings for both the mini and standard ATO fuses are identical. However, the amperage color ratings of maxi fuses use a different color scheme.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]

[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Color Ratings For STANDARD and MINI Fuses*[/SIZE][/FONT]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Fuse Amp Rating[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Identification Color[/FONT]*[/SIZE]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*3*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Violet *[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*5*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Tan *[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*7.5*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Brown*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*10*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Red*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*15*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Blue*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*20*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Yellow*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*25*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Colorless*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*30*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Green*[/SIZE][/FONT]




*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]MAXI[/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]STANDARD[/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]MINI[/SIZE][/FONT]*​
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Color Ratings For MAXI Fuses*[/SIZE][/FONT]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Fuse Amp Rating[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Identification Color[/FONT]*[/SIZE]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*20*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Yellow *[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*30*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Green*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*40*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Amber*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*50*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Red*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*60*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Blue*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*70*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Brown*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*80*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Colorless*[/SIZE][/FONT]​ 




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*OLDER TYPE FUSES *[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Many older vehicles, both foreign and domestic, use glass or ceramic fuse cartridges that were either color coded or stamped on case for current ratings. Glass fuses were used on older domestic vehicles while the ceramic were used on most older European vehicles. Ceramic fuses used an amperage color rating system while glass fuses have the amperage ratings stamped into one of the metal end caps.[/SIZE][/SIZE][/FONT]









​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FUSIBLE LINKS AND FUSE ELEMENTS*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Fusible links are divided into two categories: the fuse element cartridge and the fusible link. The construction and function of fusible links and fuse elements are similar to that of a fuse. The main difference is that the fusible link and fuse element are used to protect higher amperage electrical circuits, generally circuits 30 amps or more. As with fuses, once a fusible link or fuse element blows out, it must be replaced with a new one. [/SIZE][/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSE ELEMENT CARTRIDGE[/SIZE]*
[SIZE=-1]Fuse elements, a cartridge type fusible link, are also known as a Pacific fuses. The element has the terminal and fusing portion as a unit. Fuse elements have replaced fusible links for the most part. The housing is color coded for each current rating. Although fuse elements are available in two physical sizes and are either plug in or bolt on design, the plug-in type is the most popular.[/SIZE][/SIZE][/FONT]







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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSE ELEMENT CARTRIDGE CONSTRUCTION[/SIZE]*
[SIZE=-1]Construction of the fuse element is quite simple. A colored plastic housing contains the fusing portion element which can be viewed through a clear top. Fuse ratings are also stamped on the case.[/SIZE][/SIZE][/FONT]​







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FUSE ELEMENT COLOR IDENTIFICATION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Fuse amperage color ratings are shown below. The fusing portion of the fuse element is visible through a clear window. The amperage ratings are also listed on the fuse element.[/SIZE][/FONT]​




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Fuse Element Color Ratings - Pacific*[/SIZE][/FONT]
[SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Amperage Rating[/SIZE][/FONT]*[/SIZE]
[SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Identification Color[/SIZE][/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]30[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Pink[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]40[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Green[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]50[/FONT]*[/SIZE]
[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]*[FONT=Verdana, Arial, Helvetica, sans-serif]Red[/FONT]*[/FONT][/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]60[/FONT]*[/SIZE]
[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]*[FONT=Verdana, Arial, Helvetica, sans-serif]Yellow[/FONT]*[/FONT][/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]80[/FONT]*[/SIZE]
[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]*[FONT=Verdana, Arial, Helvetica, sans-serif]Black[/FONT]*[/FONT][/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]100[/FONT]*[/SIZE]
[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]*[FONT=Verdana, Arial, Helvetica, sans-serif]Blue[/FONT]*[/FONT][/SIZE]​ 



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSIBLE ELEMENTS[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[SIZE=-1]Fusible elements are often located near the battery by themselves.[/SIZE]
[/FONT]








​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSIBLE ELEMENTS[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[SIZE=-1]Fusible elements can also be located in relay / fuse boxes in the engine compartment.[/SIZE][/FONT]​








​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]FUSIBLE LINKS [/SIZE]*
[SIZE=-1]Fusible links are short pieces of a smaller diameter wire designed to melt during an over current condition. A fusible link is usually four (4) wire sizes smaller than the circuit that it is protecting. The insulation of a fusible link is a special nonflammable material. This allows the wire to melt, but the insulation to remain intact for safety. Some fusible links have a tag at one end that indicates its rating. Like fuses, fusible links must be replaced after they have "blown" or melted opened. Many manufacturers have replaced fusible links with fuse elements or maxi fuses.[/SIZE][/SIZE][/FONT]









​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CIRCUIT BREAKERS [/SIZE]*
[SIZE=-1]Circuit breakers are used in place of fuses for the protection of complicated power circuits such as the power windows, sunroofs and heater circuits. Three types of circuit breakers exists: The manual reset type - mechanical, the automatic resetting type - mechanical, and the automatically reset solid state type - PTC. Circuit breakers are usually located in relay/fuse boxes; however, some components like power window motors have circuit breakers built in. [/SIZE][/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CIRCUIT BREAKER CONSTRUCTION MANUAL TYPE
[/SIZE]*[SIZE=-1]A circuit breaker basically consists of a bimetal strip connected to two terminals and to a contact in between. Manual circuit breaker when tripped (current flow beyond its rating) will open and must be reset manually. These manual circuit breakers are called "non-cycling" circuit breakers.[/SIZE][/SIZE][/FONT]




​ 



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CIRCUIT BREAKER OPERATION MANUAL TYPE[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2][SIZE=-1]The circuit breaker contains a metal strip made of two different metals bonded together called a bimetal strip. This strip is in the shape of a disc and is concaved downward. When heat from the excessive current is higher than the circuit breaker current rating, the two metals change shape unevenly. The strip bends or warps upwards and the contacts open to stop current flow. The circuit breaker can be reset after it is tripped.[/SIZE] [/SIZE][/FONT]








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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]MANUAL RESET TYPE[/SIZE]*
[SIZE=-1]When a circuit breaker is opened by an over-current condition, the circuit breaker requires reset. To do so, insert a small rod (paper clip) to reset the bimetal plate as shown below. [/SIZE][/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]AUTOMATIC RESETTING TYPE - MECHANICAL[/SIZE]*
[SIZE=-1]Circuit breakers that automatically reset are called "cycling" circuit breakers. This type of circuit breaker is used to protect high current circuits, such as power door locks, power windows, air conditioning, etc. The automatically resetting circuit breaker contains a bimetal strip. The bimetal strip will overheat and open from the excess current by an overcurrent condition and is automatically reset when the temperature of the bimetal strip cools. [/SIZE][/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]AUTO RESET CONSTRUCTION AND OPERATION[/SIZE]*
[SIZE=-1]A cycling circuit breaker contains a metal strip made of two different metals bonded together called a bimetal strip. When heat from the excessive current is higher than the circuit breaker current rating the two metals change shape unevenly. The strip bends upwards and a set of contacts open to stop current flow. With no current flowing the bimetal strip cools and returns to its normal shape, closing the contacts, and resuming the current flow. Automatically resetting circuit breakers are said to "cycle" because they cycle open and closed until the current returns to a normal level.[/SIZE] [/SIZE][/FONT]​






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]AUTOMATIC RESETTING SOLID STATE TYPE - PTC[/SIZE]*
[SIZE=-1]A Polymer PTC (for Positive Temperature Coefficient) is a special type of circuit breaker called a thermistor (or thermal resistor). A PTC thermistor increases resistance as its temperature in increased. PTCs, which are made from a conductive polymer, are solid state devices, which means they have no moving parts. PTCs are commonly used to protect power window and power door lock circuits. [/SIZE][/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]POLYMER PTC CONSTRUCTION AND OPERATION
[/SIZE]*[SIZE=-1]In its normal state, the material in a polymer PTC is in the form of a dense crystal, with many carbon particles packed together. The carbon particles provide conductive pathways for current flow. This resistance is low. When the material is heated from excessive current, the polymer expands, pulling the carbon chains apart. In this expanded "tripped" state, there are few pathways for current. When current flow exceeds the trip threshold, the device remains in the "open circuit" state as long as voltage remains applied to the circuit. It resets only when voltage is removed and the polymer cools. PTCs are used to protect power window and power door lock circuits. [/SIZE][/SIZE][/FONT]​



​[SIZE=-1][/SIZE] 



فى نهاية الموضوع نرجو منكم الدعاء


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## mohamed abouzahra (6 أغسطس 2007)

الموضوع الخامس عن المقاومة المتغيرة 
ولها استخدمات كتير اوى فى السيارات من ابسطهم مقياس كمية الوقود ايضا معرفة كمية الهواء فى الانظمة القديمة وغيرها نشوف الموضوع احسن .

*Variable Resistors*
________________________________


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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RESISTORS
*All electrical circuits require resistance to operate correctly. Resistors are sometimes added to an electrical circuit to limit current flow, create voltage drops, or provide different operating modes. All resistors are rated in both a fixed ohm value of resistance and a power rating in watts. (Watt = Volts X Amps)[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Three basic categories of resistors are used in automotive electrical systems:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*1. Fixed;*[/SIZE][/FONT]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]2. Stepped or tapped;[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]3. Variable.[/FONT]*[/SIZE]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Each has different characteristics and usage ranging from a simple fan circuit to a completed computer circuit.[/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FIXED RESISTORS*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Fixed-value resistors are divided into two category types of resistors: *Carbon / Metal Oxide and Wire-Wound.*
[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Carbon and Metal Oxide Film[/SIZE][/FONT]*[/SIZE][/FONT]






[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Wire-Wound*[/SIZE][/FONT]





*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Fixed Resistor
Electrical Symbol[/SIZE][/FONT]*​ 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CARBON RESISTORS
*Carbon resistors are commonly used in electronic systems. Carbon is mixed with binder; the more carbon, the lower the resistance. Carbon resistors have a fixed resistance value and are used to limit current flow. They are rated in watts and most have color-code bands to show the resistance value. A typical resistor has a watt rating from 0.125W to 2.0 W. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Note: Metal-Oxide Film is sometimes used instead of carbon. While carbon is commonly used for ratings up to 0.5 watt , Metal-Oxide Film provide, better high-temperature satiability and is often used for 1.0 - 2.0 watt resistors.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Carbon[/SIZE][/FONT]*[/SIZE][/FONT]





[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Metal Oxide Film[/SIZE][/FONT]*[/SIZE][/FONT]​ 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RESISTOR RATING COLOR BANDS*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The first two bands set the digit or number value of the resistor. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The third band, also known as the multiplier band, is the number of zeros added to the number value.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The last band is the Tolerance band. Example: +/- 10%[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RESISTOR COLOR BAND CHART
*The chart below is used to interpret the color bands on the carbon resistor. Another chart is used to show the value of tolerance band colors (not shown).[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Using the illustration below:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The first color band is *Green* with a value of "*5*".
The second color band is *Red* with a value of "*2*".
The third band is *Black* with a value of "*0*" zero. (No zeros are added)[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]So the resistor has a base value of *52 ohms*. [/SIZE][/FONT]









​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*READING COLOR BANDS - TOLERANCE VALUE
*Resistors vary in tolerance (accuracy). Common tolerance values are 20%, 10%, 5%, 2%, or 1%, simply meaning the maximum percent allowable difference the resistor value actually is from the designed value rating. A 1% resistor is a higher quality resistor than one with a 20% rating.[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The tolerance band (last band) is *silver* with a value of 10%. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]So, the resistance value is "*52 ohms plus or minus 5.2 ohms*" (46.8 to 57.2 ohms).[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT]​




[SIZE=-1][/SIZE] 



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*FIXED RESISTOR USAGE
*Fixed resistors are often used in voltage division circuits. One example is the computer sensor circuit shown below. Notice two resistors, R1 and R2, are placed in series. A fixed resistor R1, known as a pull-up resistor, is used to create a voltage drop point. As the resistance of water temp sensor (R2) changes, so does its voltage drop. This change also changes the voltage drop of R1. A monitor circuit inside the computer measures this voltage drop in between the two resistors. [/SIZE][/FONT]​


[SIZE=-1][/SIZE]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]WIRE-WOUND RESISTORS
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Wire-wound resistors are made with coils of resistance wire. Often enclosed in ceramic to help dissipate heat and protect the resistor wire, they are accurate and heat stable. The resistance value is often marked. Wire-wound are used in higher watt circuits often 2W or higher. An ignition ballast resistor is an example of a wire wound resistor.[/SIZE][/FONT]​








​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]STEPPED OR TAPPED RESISTORS
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A stepped or tapped resistor has two or more fixed taps that provide different resistance values. These taps allow current to flow through all or part of the resistor, which changes the amount of current flowing through the circuit. Stepped resistors can also be encased in ceramic and are nothing more than a series of fixed resistors placed end to end. [/SIZE][/FONT]​






[SIZE=-1][/SIZE]

​


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## mohamed abouzahra (6 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]STEPPED RESISTOR OPERATION
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]An example of a stepped resistor in operation is the blower motor circuit shown below. Notice the blower resistor is in series with the blower motor. Higher resistance in series will lower the current flow; thus, higher blower resistor resistance will result in lower blower speeds. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In low speed current flows through the entire resister from pin#3 though pin#1 to ground (shown in *blue*). The motor will be in low speed because less current is flowing. Moving the blower switch to medium 2 speed opens a path for current out pin #4 to ground. Current flows through pin#3 and out pin#4 to ground (shown in *green*). Current will flow through only part of the resistor. The motor will be in medium 2 speed causing the blower motor to spin faster compared to low speed because more current is flowing through the circuit. [/SIZE][/FONT]​




​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]VARIABLE RESISTORS
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Variable resistors provide an infinite amount of resistance values. Variable resistors are used by electrical circuits to provide information on temperature, position, or light source.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]There are four types of variable resistors used:[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]Rheostats[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Potentiometers*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Thermistors *[/SIZE][/FONT]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]Photoresistor [/FONT]*[/SIZE]​ [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]




*[SIZE=-1]Generic Variable Resistor
Electrical Symbol[/SIZE]*[/SIZE][/FONT]​ 



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RHEOSTAT
*Rheostats at one time were used in the headlamp switch to dim or brighten dash panel lighting and pre-OBDII fuel gauge sending units. Rheostats have two connections, one to the fixed end of a resistor and the other to a sliding contact on the resistor. Turning the control moves the sliding contact away from or toward the fixed end, increasing or decreasing the resistance. Rheostats control resistance, thus controlling current flow.[/SIZE][/FONT]​



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*
[SIZE=-1]Rheostat Symbol [/SIZE]*[/SIZE][/FONT][SIZE=-1][/SIZE]





[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*
[SIZE=-1]Variable Resistor Symbol[/SIZE]*[/SIZE][/FONT][SIZE=-1][/SIZE]​


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RHEOSTAT OPERATION
*As the wiper moves along the rheostat it exposes more or less of the resistor. Moving the wiper towards the high places a small portion of the resistor in series with the light, causing the light to glow bright. Moving the wiper toward the low, places a larger portion of the resistor in series with the lamp; this increased resistance causes less current to flow lowering the intensity of the light. Rheostats are not used on computer circuits because of temperature variations on the resistor when the wiper arm is moved. [/SIZE][/FONT]​


[SIZE=-1][/SIZE]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]POTENTIOMETER
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Potentiometers are used to measure changes in position. Potentiometers have three connections or legs: the *reference*, *signal*, and *ground*. The reference is at one end of a resistor and the Ground is at the other end. Current flows from the *Reference* through the resistor to *Ground* creating a voltage drop across the resistor. The *Signa*l is a sliding contact (movable wiper arm) that runs across the resistor. Unlike a rheostat, its main purpose is not to vary resistance but to vary the voltage in a circuit.[/SIZE][/FONT]​




*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Potentiometer Symbol[/SIZE][/FONT]* 






*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Variable Resistor Symbol[/SIZE][/FONT]*


 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]POTENTIOMETER OPERATION
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Remember a potentiometer has three legs, the reference (R), the signal (S) , and the ground (G) as shown below. 5 volts is supplied to the reference, current flows from the reference (R) through the entire resistor to ground (G). The Signal wiper slides across the resistor changing measure voltage as it moves. As the wiper moves towards the reference (R), the measured signal voltage at (S) will increase. As the wiper moves away from the Reference (R) towards ground (G), the measured signal voltage drops. [/SIZE][/FONT]​


[SIZE=-1][/SIZE]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]POTENTIOMETER APPLICATIONS
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Since potentiometer are used to measure changes in position they naturally are used for throttle, EGR, AC blend door, and power seat position sensors. All potentiometers have three wires and are used to measure position changes. [/SIZE][/FONT]



[SIZE=-1][/SIZE]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]THERMISTOR
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Thermistors are resistors that change resistance as the temperature changes. These are ideal in electrical circuits where measuring temperature change is required. There are two types of thermistors: [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*NTC (Negative Temperature Coefficient)* 
NTC thermistors: as the temperature goes down, the resistance goes up, and as the temperature goes up, the resistance drops. This type is used today in automotive applications.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*PTC (Positive Temperature Coefficient)
*PTC thermistors: as the temperature go down, the resistance goes down also, and as the temperature goes up, the resistance increases.[/SIZE][/FONT]​



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]Thermistor
Electrical Symbol[/SIZE]*[/SIZE][/FONT] 

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]THERMISTOR APPLICATIONS
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Thermistors are used as Air, Coolant, EGR, and Automatic Air Temperature sensors. All thermistors have two wires and are used to measure temperature changes. When placed in series with a fixed (pull-up) resistor, thermistors create a variable voltage drop circuit, which is ideal for use by computer circuits. Engine coolant temperature sensor (ECT) is shown below.[/SIZE][/FONT]​


[SIZE=-1][/SIZE]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]THERMISTOR OPERATION
[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]In the example below, as the engine warms up, R2 (water temp sensor) increases in temperature; this lowers the resistance of R2. The drop in R2 resistance results in a decreased voltage drop across R2 (less voltage is used). This decreased voltage drop across R2 causes the voltage drop across R1 to increase. R1 now uses more voltage. This increased voltage drop of R1 results in a lowered measured voltage by the monitor circuit and is seen by the computer as an increase in engine temperature. The reverse is true as the water temp sensor cools. [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*



*[/SIZE][/FONT][SIZE=-1][/SIZE]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]PHOTORESISTORS[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A photoresistor, or photoconductive cell, is basically a light sensitive resistor whose resistance changes as light is exposed to it. Basically photoresistors change resistance as light intensity changes. The photoresistor has high resistance with no light exposed and decreases in resistance as light intensity increases. A common automotive use for photoresistors is the automatic headlamp circuit.[/SIZE][/FONT]​





[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2][SIZE=-1]*[FONT=Arial, Helvetica, sans-serif]Photo Resistor
Electrical Symbol[/FONT]*[/SIZE][/SIZE][/FONT]​[SIZE=-1][/SIZE] 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]PHOTORESISTOR OPERATION [/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A photoresistor is placed in the automatic headlight circuit shown below. The photoresistor operates a normally closed headlight relay. During daylight driving light shines on the photoresistor, lowering its resistance, causing current to flow allowing the relay coil to energize, opening the relay contacts, thus preventing the headlights from operating. When the photoresistor is in darkness, its resistance increases preventing enough current flow through the relay coil to keep the relay contacts open. The closed relay contacts allow current to flow to the headlights causing them to turn on. Photoresistors respond slowly to changes in light intensity and may require several minutes to stabilize.[/SIZE][/FONT]​




ان شاء الله سوف ننتقل الى الموضوع السادس​


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## م/عماد (6 أغسطس 2007)

_انامعاك فى الموضوع الشديد بس عايزك تفصل تفصيل كامل فى ميكانيكاالسيارات_


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## mohamed abouzahra (6 أغسطس 2007)

اخى العزيز م / عماد 
حدد لى الموضوع الى انت عايزة وان شاء الله لو فى مقدرتى انى اجيبة ان شاء الله هجيبة 

بس لاحظ ان مهندس السيارات الى بقى مهندس كهرباء يعنى شغل السيارات الحديثة نسبة الميكانيكا بة بسيطة جدا 
حتى محركات الديزل الجديدة .

وعلى العموم انا تحت امرك فى اى شى تحتاجة ان شاء الله ويوفقنى فى ذلك .


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## elbary (6 أغسطس 2007)

بارك الله فيك


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## mohamed abouzahra (6 أغسطس 2007)

كل الموضوع دة ومفيش ردود 
يعنى بلاش احسن الواحد يكمل باقية الدورة ما دام الموضوع مفيش حد قد يستفيد منة 

ومشكور على الرد يا بشمهندس (elbary


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## eng_mechanic (6 أغسطس 2007)

موضوع جميل بس يا ريت اللى عنده فيديو على السيارات يراسلنى على ****** علىeng_mechanic2005واكون شاكر ليكم جميعا


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## eng_mechanic (6 أغسطس 2007)

شكرا للرقابه


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## mohamed abouzahra (7 أغسطس 2007)

eng_mechanic قال:


> شكرا للرقابه


 

مشكوررررر اخى على ردك


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## mohamed abouzahra (7 أغسطس 2007)

نبدا الموضوع السادس وسوف نتكلم عن الكتاوت 
*Understanding Relays*
_____________________________
-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_--_-_-_-_-_-_-_-_--_--


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAYS*
Relays are used throughout the automobile. Relays which come in assorted sizes, ratings, and applications, are used as remote control switches. A typical vehicle can have 20 relays or more.[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]RELAY LOCATIONS[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Relays are located throughout the entire vehicle. Relay blocks, both large and small, are located in the engine compartment; behind the left or right kick panels, or under the dash are common locations. Relays are often grouped together or with other components like fuses or placed by themselves.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]



[/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]RELAY POSITION[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1] IDENTIFICATION[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[SIZE=-1]Relay / Fuse block covers usually label the location and position of each fuse, relay, or fuse element contained within.[/SIZE][/FONT]




​ 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAY APPLICATIONS*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1][SIZE=-2]
[SIZE=-1]Relays are remote control electrical switches that are controlled by another switch, such as a horn switch or a computer as in a power train control module. Relays allow a small current flow circuit to control a higher current circuit.[/SIZE][/SIZE][/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1] Several designs of relays are in use today, 3-pin, 4-pin, 5-pin, and 6-pin, single switch or dual switches.[/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAY OPERATION*
All relays operate using the same basic principle. Our example will use a commonly used 4 - pin relay. Relays have two circuits: A control circuit (shown in GREEN) and a load circuit (shown in RED). The control circuit has a small control coil while the load circuit has a switch. The coil controls the operation of the switch. [/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1][SIZE=-2]*[SIZE=-1]RELAY ENERGIZED (ON)[/SIZE]*
[/SIZE]Current flowing through the control circuit coil (pins 1 and 3) creates a small magnetic field which causes the switch to close, pins 2 and 4. The switch, which is part of the load circuit, is used to control an electrical circuit that may connect to it. Current now flows through pins 2 and 4 shown in RED, when the relay is energized.[/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAY DE-ENERGIZED (OFF)*[SIZE=-2]
[/SIZE]When current stops flowing through the control circuit, pins 1 and 3, the relay becomes de-energized. Without the magnetic field, the switch opens and current is prevented from flowing through pins 2 and 4. The relay is now OFF.[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*RELAY OPERATION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [SIZE=-1]When no voltage is applied to pin 1, there is no current flow through the coil. No current means no magnetic field is developed, and the switch is open. When voltage is supplied to pin 1, current flow though the coil creates the magnetic field needed to close the switch allowing continuity between pins 2 and 4. [/SIZE][/SIZE][/FONT]​












​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*NORMALLY DESIGN ID*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Relays are either Normally Open or Normally Closed. Notice the position of the switches in the two relays shown below. Normally open relays have a switch that remains open until energized (ON) while normally closed relays are closed until energized. Relays are always shown in the de-energized position (no current flowing through the control circuit - OFF). Normally open relays are the most common in vehicles; however either can be use in automotive applications. [/SIZE][/SIZE][/FONT]​




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]Normally Open (NO)[/SIZE]*[/SIZE][/FONT] 




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]Normally Closed (NC)[/SIZE]*[/SIZE][/FONT]​


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]NORMALLY CLOSED RELAYS[/SIZE]*
[SIZE=-1]The operation of a Normally Closed relay is the same to that of a Normally Open relay, except backwards. In other words, when the relay control coil is NOT energized, the relay switch contacts are closed, completing the circuit through pins 2 and 4. When the control coil is energized, the relay switch contacts opens, which breaks the circuit open and no continuity exists between pins 2 and 4.[/SIZE][/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]DE - ENERGIZED (OFF) [/SIZE]*[/SIZE][/FONT] 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]



[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]ENERGIZED (ON) [/SIZE]*[/SIZE][/FONT]​ 

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]ACTUAL RELAY DESIGN[/SIZE]*
[SIZE=-1]Current flows through the control coil, which is wrapped around an iron core. The iron core intensifies the magnetic field. The magnetic field attracts the upper contact arm and pulls it down, closing the contacts and allowing power from the power source to go to the load.[/SIZE][/SIZE][/FONT]




 




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]RELAY VARIATIONS[/SIZE] *
[SIZE=-1]Other relay variations include three and five pin relays. A 3-PIN relay instead of two B+ input sources, this relay has one B+ input at pin 1. Current splits inside the relay, supplying power to both the control and load circuits. A 5-PIN relay has a single control circuit, but two separate current paths for the switch: One when the relay is de-energized (OFF - no current through the control coil) and the other the energized (ON - current is flowing through the control coil). When the 5-PIN relay is de-energized (OFF), pins 4 and 5 have continuity. When the relay is energized (ON), pins 3 and 5 have continuity. [/SIZE][/SIZE][/FONT]

[SIZE=-1]



[/SIZE]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*3 - PIN*[/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]4 - PIN[/SIZE]*[/SIZE][/FONT] [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*



*[/SIZE][/FONT] 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*5 - PIN *[/SIZE][/FONT]​ 


ISO STANDARDIZED RELAYS
ISO relays were designed to try and standardize relay connections, making it easier to test and design systems. ISO relays are currently used by almost all automotive manufacturers today. Both 4 and 5 pin designs are used in both standard mini and micro sizes. FYI: ISO is short for International Standard Organization. 





*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]STANDARD MINI SHOWN[/SIZE][/FONT]*



STANDARD MINI ISO RELAYS TYPES
Below are two popular standard MINI ISO relay configurations. The size of a ISO Standard MINI relay is a 1" square cube. Both 4 and 5 pins designs are used. 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*5 PIN
MINI RELAY*[/SIZE][/FONT]








​


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*4 PIN
MINI RELAY*[/SIZE][/FONT]













[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]ISO MICRO RELAY TYPES[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]
Below are two popular MICRO ISO relay configurations. The size of a ISO MICRO relay is a 1" x 1" x 1/2" square (1/2 as thick as a Mini relay). Both 4 and 5 pins designs are used. [/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*5 PIN
MICRO RELAY*[/SIZE][/FONT]




​




​




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*4 PIN
MICRO RELAY*[/SIZE][/FONT]




​








[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]VOLTAGE SPIKES [/SIZE]*
[SIZE=-1]When the switch is closed (shown left), current flows through the coil from positive to negative as shown in red. This current flow creates a magnetic field around the coil. The top of the coil is positive, and the bottom is negative. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]When the switch is opened (shown on right), current stops flowing through the control circuit coil, and the magnetic field surrounding the coil cannot be maintained. As the magnetic field collapses across the coil, it induces a voltage into itself, creating a reverse polarity voltage spike of several hundred volts. Although the top of the coil is still 12 volts positive, the bottom of the coil produces several hundred positive volts (200+ volts or more); 200 is "more positive" and stronger than 12 volts, so current flows from the bottom of the coil up towards the top.[/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]VOLTAGE SUPPRESSION RELAYS[/SIZE]*
[SIZE=-1]Relays are often controlled by a computer. When relays are controlled by semiconductors such as transistors, they require some type of voltage suppression device. Solid state circuits are vulnerable to voltage spikes. Voltage spikes slam against transistors, destroying them. While some computer circuits have voltage suppression built inside the computer, others rely on voltage suppression from within the relay. High ohm resistors, diodes, or capacitors can be used for voltage suppression. Diodes and resistors are the most common. NOTE: Relays are usually clearly marked if a suppression diode or resistor are present.[/SIZE][/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]RELAYS WITH DE-SPIKING DIODES[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1] [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]A de-spiking (clamping) diode is connected in parallel with the relay coil. It is in the reverse biased position when the relay is turned on; therefore no current will flow through the diode. When the relay control circuit is opened (turned OFF), current stops flowing through the coil, causing the magnetic field to collapse. The magnetic lines of force cut through the coil and induce a counter voltage (a voltage in reverse polarity) into the winding. The counter voltage begins to raise. When the bottom side of the diode sees .7 volts more positive voltage than the top, the diode becomes forward biased, allowing the excess voltage to pass, completing the circuit to the other end of the coil. The current flows around in the diode and coil circuit until the voltage is dissipated. [/SIZE][/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]RELAYS WITH DE-SPIKING RESISTORS[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1] [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]High ohm resistors are sometimes used instead of diodes. A resistor is more durable than a diode and can suppress voltage spikes similar to a diode, but the resistor will allow current to flow through it whenever the relay is on. Therefore resistance of the resistor must be fairly high (about 600 ohms) in order to prevent too much current flow in the circuit. High ohm resistors are not quite as efficient at suppressing a voltage spike as diodes.[/SIZE][/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CIRCUIT IDENTIFICATION[/SIZE]*
[SIZE=-1]Relays are easy to test but often misunderstood. Using a 4 pin relay for our example, we must first identify the pins. Some manufacturers place a diagram and pin ID on the outside of the relay case to show which pins are part of the control circuit and which pins are part of the load circuit. [/SIZE][/SIZE][/FONT]













[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CONTINUITY CHECK FOR PIN ID[/SIZE]*
[SIZE=-1]If the relay is not labeled, use an ohmmeter and check to see which pins are connected to each other. You should typically find an ohm value of approximately 50 to 120 ohms between two of the pins. This is the control circuit. If the coil is less that 50 ohms it could be suspect. Refer to manual to verify reading. The remaining two pins should read OL (infinite) if it's a normally open relay, or 0 ohms (continuity) if it's a normally closed relay. If the readings are correct, proceed to the next test. Note: If none of the relay pins showed a coil value and all pins show OL or 0 ohms, the control coil is damaged and should be replaced. [/SIZE][/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*PRACTICAL TESTING*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Once the pins have been identified, energize the control circuit by supplying B+ to pin 1 and a ground to pin 3. A faint "click" will be heard; although this "click" means the switch has moved (closed), it does not mean the relay is good. The load circuit switch contacts could still be faulty (high resistance), and further testing is required. A common mistake technicians make is they hear a "click" and assume the relay is good. Take the extra step and verify operation.[/SIZE] [/SIZE][/FONT]




 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CAUTION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Testing relays with built in clamping diodes require a special procedure. These relays are polarity sensitive; placing B+ to the wrong pin (backwards) while performing a practical test will forward bias the diode and damage the diode, thus destroying the protective quality of the diode.[/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*OPERATIONAL CHECK WITH TESTLIGHT*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Now start the second part of the test. Energize the relay (control side) by supplying B+ to pin 1 and a ground to pin 3. A[/SIZE] [SIZE=-1]click should be heard. With the relay still energized, supply B+ pin 2 of the load circuit. The test light will be on. De-energize (remove B+) the control circuit at pin 1; the test light at pin 4 should go off. A test light is preferred because a test light will draw current through the switch.[/SIZE][/SIZE][/FONT]




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CAUTION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Testing relays with built in clamping diodes require a special procedure. These relays are polarity sensitive; placing B+ to the wrong pin (backwards) while performing a practical test will forward bias the diode and damage the diode, thus destroying the protective quality of the diode.[/SIZE][/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]OPERATIONAL CHECK WITH VOLTMETER[/SIZE]*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]
A voltmeter can be substituted in place of a test light; however be aware if the contacts are partially burned, the voltmeter will show voltage indicating good contact even when bad. Remember high impedance digital voltmeters draw almost no current. Energize the relay (control side) by supplying B+ to pin 1 and a ground to pin 3. A click should be heard. With the relay still energized supply B+ to pin 2 of the load circuit. Connect the RED lead to pin 4 and the BLACK lead to ground. The voltmeter will indicate source voltage (12V). De-energize (remove B+) the control circuit at pin 1; the voltmeter should now read "zero". Re-energize the relay and the voltmeter should return to 12 volts. [/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CAUTION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Testing relays with built in clamping diodes require a special procedure. These relays are polarity sensitive; placing B+ to the wrong pin (backwards) while performing a practical test will forward bias the diode and damage the diode, thus destroying the protective quality of the diode.[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*OPERATIONAL CHECK WITH AN OHMMETER*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]An ohmmeter can also be used to test the load circuit, but the same problem as the voltmeter comes into play. Energize the relay (control side). Supply B+ to pin 1 and a ground (neg.) to pin 3. A click should be heard. Place the leads on an ohmmeter to across pin 2 and pin 4. Assuming it is a normally open relay the ohmmeter will indicate a complete circuit (close to zero -0 ohms). De-energize the control circuit at pin 1(remove B+). The ohmmeter should indicate OL (an open circuit - infinite). Re-energize the relay and the ohmmeter should return to "zero" ohms. Note: some manufactures provide a maximum ohm value when the switch contacts are closed, example 5 ohms max.[/SIZE][/SIZE][/FONT]




 [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CAUTION*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Testing relays with built in clamping diodes require a special procedure. These relays are polarity sensitive; placing B+ to the wrong pin (backwards) while performing a practical test will forward bias the diode and damage the diode, thus destroying the protective quality of the diode.[/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*OPERATIONAL CHECK FOR RELAY VOLTAGE SUPPRESSION DIODES*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]An ANALOG OHMMETER must be used. This test cannot be performed with a digital meter. The analog meter sends out a higher voltage which is required to forward bias the diode. Place the ohmmeter across the control circuit and record reading. Reverse the leads and check the control circuit again. A functioning diode will be indicated by have two different readings. A faulty diode will have the same reading in both directions.[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Current from the ohmmeter flows through the control coil, in one direction. By reversing the leads, you send current in the opposite direction through the control coil. One of the two directions the diode will be forward biased(on), creating two paths for current thus lowering resistance. With the leads in the other direction, the diode in will be reversed biased (off) creating only one path, with higher resistance. [/SIZE][/FONT]

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## mohamed abouzahra (7 أغسطس 2007)

وبعد كدة ندخل فى الجد شوية 

ان شاء الله نبدا فى 
اساسيات البطارية
*Battery Basics*


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica][SIZE=-1]*THE AUTOMOTIVE BATTERY
*A lead-acid storage battery is an electrochemical device that produces voltage and delivers electrical current. The battery is the primary "source" of electrical energy used in vehicles today. It's important to remember that a battery does not store electricity, but rather it stores a series of chemicals, and through a chemical process electricity is produced. Basically, two different types of lead in an acid mixture react to produce an electrical pressure called voltage. This electrochemical reaction changes chemical energy to electrical energy and is the basis for all automotive batteries. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT]








​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*THE PURPOSE OF THE BATTERY
*The battery supplies electricity when the:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*ENGINE IS OFF:* Electricity from the battery is used to operate lighting, accessories, or other electrical systems when the engine is not running. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*ENGINE IS STARTING:* Electricity from the battery is used to operate the starter motor and to provide current for the ignition system during engine cranking. Starting the car is the battery's most important function.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*ENGINE IS RUNNING*: Electricity from the battery may be needed to supplement the charging system when the vehicle's electrical load requirements exceed the charging system's ability to produce electricity. Both the battery and the alternator supply electricity when demand is high.[/SIZE][/FONT]
[SIZE=-1]



[/SIZE]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERIES - Primary or Secondary*[/SIZE][/FONT] 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Batteries can either be *a primary cell*, such as a flashlight battery once used, throw it away, or a *secondary cell*, such as a car battery (when the charge is gone, it can be recharged). [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*PRIMARY CELL:* Because the chemical reaction totally destroys one of the metals after a period of time, primary cells cannot be recharged. Small batteries such as flashlight and radio batteries are primary cells.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*SECONDARY CELL:* The metal plates and acid mixture change as the battery supplies voltage. As the battery drains the metal plates become similar and the acid strength weakens. This process is called discharging. By applying current to the battery in the reverse direction, the battery materials can be restored, thus recharging the battery. This process is called charging. Automotive lead-acid batteries are secondary cells and can be recharged.[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERIES*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]* - Wet or Dry Charged
*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]Batteries can be produced as Wet-Charged, such as current automotive batteries are today, or they can be Dry-Charged, such as a motorcycle battery where an electrolyte solution is added when put into service.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*WET-CHARGED:* The lead-acid battery is filled with electrolyte and charged when it is built. During storage, a slow chemical reaction will cause self-discharge. Periodic charging is required. Most batteries sold today are wet charged.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*DRY-CHARGED:* The battery is built, charged, washed and dried, sealed, and shipped without electrolyte. It can be stored for up to 18 months. When put into use, electrolyte and charging are required. Batteries of this type have a long shelf life. Motorcycle batteries are typically dry charged batteries.[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERY CONSTRUCTION *[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]An automobile battery contains a diluted sulfuric acid electrolyte and positive and negative electrodes, in the form of several plates. Since the plates are made of lead or lead-derived materials, this type of battery is often called a lead acid battery. A battery is separated into several cells (usually six in the case of automobile batteries), and in each cell there are several battery elements, all bathed in the electrolyte solution. [/SIZE][/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CELL OPERATION[/SIZE]*
[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Two dissimilar metals placed in an acid bath produce electrical potential across the poles. The cell produces voltage by a chemical reaction between the plates and the electrolyte. The positive plate is made of reddish-brown material such as Lead Dioxide (PBO2) while the negative plate is made of grayish material called Sponge Lead (PB). The acid bath is a mixture of sulfuric acid and water cell electrolyte. Together a cell element is formed. [/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CYCLING[/SIZE]*
[SIZE=-1]The battery stores electricity in the form of chemical energy. Through a chemical reaction process the battery creates and releases electricity as needed by the electrical system or devices. Since the battery loses its chemical energy in this process, the battery must be recharged by the alternator. By reversing electrical current flow through the battery the chemical process is reversed, thus charging the battery. The cycle of discharging and charging is repeated continuously and is called "battery cycling".[/SIZE][/SIZE][/FONT]​


[SIZE=-1][/SIZE]


​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]DEEP CYCLING[/SIZE]*
[SIZE=-1]Although batteries do cycle continuously, they do not cycle deeply. Deep cycling is when the battery is completely discharged before recharge. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Automotive batteries* are not designed as deep cycle batteries. Automotive batteries are designed to be fully charged when starting the car; after starting the vehicle, the lost charge is replaced by the alternator. So the battery remains fully charged. Deep cycling an automotive battery will cause damage to the plates and shorten battery life. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Marine or golf cart batteries (Deep Cycle Batteries) *on the other hand are designed to be completely discharged before recharging. Because charging causes excessive heat which can warp the plates, thicker and stronger plate grids are used. Normal automotive batteries are not designed for repeated deep cycling and use thinner plates. [/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]CELL VOLTAGE[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Each cell element of the battery produces approximately 2.1 volts, regardless of the quantity or size of the plates. Automobile batteries have six cells that are connected in series, which produces a total voltage of 12.6 volts. [/SIZE][/FONT]​


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]BATTERY CELL ELEMENT[/SIZE]*
[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The key to battery operation is the cell element. Positive plates and negative plates are each connected together by separate plate straps. These groups of positive and negative plates are then placed alternately, separated by micro-porous separators. Assembled together, the plates and separators form a battery cell element. Grouping the plates in this way serves to enlarge the surface area between the active materials and the electrolyte, thus allowing a greater amount of electricity to be supplied. In other words, the battery capacity is increased because of the increase in surface area. More plate surface area means the battery can deliver more current.[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]PLATES [/SIZE]*
[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Battery plates are constructed of a lead alloy containing a percentage of either Antimony or Calcium. The plates are designed as a thin flat grid, grids crossing at right angles (shown below) or grids crossing diagonally at different angles which reduces internal resistance. The grid provides the necessary framework for active material to be pasted onto the plate, making either a positive or a negative plate. The active material on a charged positive plate is a reddish-brown Lead Dioxide (PBO2), while the active material on a charged negative plate is a grayish Sponge Lead (PB).[/SIZE][/FONT]​




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]GEL CELL BATTERIES[/SIZE]*
[SIZE=-1]A gel battery design is typically a modification of the standard lead acid automotive. A gelling agent is added to the electrolyte to reduce movement inside the battery case. Many gel batteries also use one way valves in place of open vents, this helps the normal internal gasses to recombine back into water in the battery, reducing gassing. The spiral design provides more plate surface area and closer plate spacing resulting in a lower internal resistance. This low resistance provides more power in a smaller battery case and the ability to recharge much faster.[/SIZE][/SIZE][/FONT]​




​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERIES*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]* - Antimony, Calcium, or Gel
*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica][SIZE=-1]Several variations of the Lead -Acid battery are used today. Variations to the battery plate material and electrolyte solution provide different battery characteristics. Construction is basically the same; however, the materials used are slightly different.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica][SIZE=-1]*1. Lead Antimony* ( Most commonly used ).
Is commonly used in conventional lead acid battery which uses lead antimony cell plates.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Advantages:*
1. Longer service life than Calcium batteries.
2. Easier to recharge when completely discharged.
3. Lower cost.[/SIZE][/FONT] ​[FONT=Verdana, Arial, Helvetica][SIZE=-1]*2. Lead Calcium* ( AC Delco maintenance free batteries ).
Is a maintenance free lead acid battery which uses lead calcium cell plates.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Advantages:*
1. Larger electrolyte reserve area above the plates.
2. Higher Cold Cranking Amp ratings.
3. Little or No maintenance.[/SIZE][/FONT] ​[FONT=Verdana, Arial, Helvetica][SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]3. Recombination (Gel Cell)[/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif] ( Optima batteries and some others ).[/FONT][/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]
Is a completely sealed lead acid battery which uses an electrolyte that is a gel (solid) rather than a liquid. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Advantages:*
1. No liquid electrolyte to spill or leak.
2. Can be Deep Cycled several time without damage.
3. Totally corrosion and maintenance free.
4. Three to four times longer battery life than regular batteries.
5. More plate surface and closer plate spacing provides a compact case size.[/SIZE][/FONT]​ 

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]LEAD ANTIMONY VS. LEAD CALCIUM[/SIZE]*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]Lead-Antimony Cast Grid[/SIZE]*[SIZE=-1]
Conventional Low-Maintenance batteries use grids of Lead-antimony which is readily available, inexpensive, easy to cast, and provide a rechargeable battery that offers optimum efficiency and low cost. Lead antimony is used in *Low-Maintenance batteries. *[/SIZE][/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Such batteries are built to reduce internal heat and water loss. Battery construction provides a deeper well area to allow a slight water loss over the life of the battery. Under normal conditions, the addition of water should not be required. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Lead-Calcium Grid
*The maintenance-free batteries, such as Delco Freedom batteries, uses calcium. The lead-calcium grid is strong, more resistant to corrosion as well as overcharging, gassing, water usage, and self-discharge, all of which shorten battery life in conventional lead-acid batteries. Lead calcium is used in *Maintenance Free batteries*. Battery construction provides a [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]deeper well area to allow a slight water loss over the life of the battery. No provision for adding water to the cells is provided because the battery is sealed.[/SIZE][/FONT]

​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*ELECTROLYTE*
Battery electrolyte is a mixture of 64% [FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]distilled water (H20)[/SIZE][/FONT] [SIZE=-1]and 36% [/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]sulfuric acid (SO4)[/SIZE][/FONT][SIZE=-1]. Batteries today have an electrolyte with a specific gravity of 1.270 (at 20'C, 68'F) when fully charged. Specific Gravity is the weight of a given volume of liquid in comparison to the weight of the same volume of water. The higher the specific gravity of a liquid the denser (thicker) it is. Testing specific gravity will be discussed in the Battery Service Module.[/SIZE][/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]SPECIFIC GRAVITY OF ELECTROLYTE[/SIZE]*
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Specific gravity means exact weight. A "Hydrometer" or a "Refractometer" compares the exact weight of electrolyte with that of water. Electrolyte in a charged battery is stronger and heavier than electrolyte in a discharged battery. By weight, the electrolyte in a fully charged battery is about 36% acid and 64% water. The specific gravity of water is 1.000, and the specific gravity of sulfuric acid is 1.835, which means the acid is 1.835 times heavier than the water. The battery electrolyte mixture of water and acid has a specific gravity of 1.270 and is usually stated as "twelve and seventy." [/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERY SPECIAL HANDLING*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]The electrolyte inside the battery is a mixture of sulfuric acid and water. Sulfuric acid is very corrosive and can cause severe injury to your skin and eyes. Always wear protective goggles, gloves, and apron while servicing the battery. If it gets on your skin, flush with a large quantity of water immediately; if it gets in your eyes, flush with large quantities of water immediately (a mild solution of baking soda and water will neutralize the acid) and seek medical attention as soon as possible. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Because sulfuric acid will eat through clothing, it is advisable to wear proper work clothing when handling batteries. When charging the battery, hydrogen gas is released so it is extremely important to keep flames or sparks away from the battery to prevent explosion. [/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERY CASE*
The battery case holds the electrolyte and the individual battery cell elements. It is divided into six compartments or cells. The plates are raised up off the bottom of the case with ribs to prevent them from shorting out if any of the active materials (lead, etc.) should happen to fall from the plates. The case is made of polypropylene, hard rubber, and plastic base materials. Some battery manufacturers use translucent plastic cases which allow checking electrolyte level without removing vent caps[/SIZE][/FONT][SIZE=-1]. [FONT=Verdana, Arial, Helvetica, sans-serif]These cases often have "upper" and "lower" electrolyte level markers on the outside of the case. [/FONT][/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1][/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]VENT CAPS[/SIZE]*
[SIZE=-1]Vent [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]caps cover the holes that are used for adding electrolyte. They are also designed to separate the sulfuric acid mist and the hydrogen gas that forms when the battery charges. The caps are designed to the sulfuric acid mist to condense and drop back into the battery and allow hydrogen gas to escape through the vent holes to the atmosphere. Vent caps can cover each individual cell as shown below. Note:Many Gel Cell Batteries use a one way check valve enplane of vents.[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]VENT CAP STRIPS
[/SIZE]*[SIZE=-1]Most batteries [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]today use vent cap strips that cover multiple cells (shown below). The caps are are designed to allow hydrogen gas to escape and sulfuric acid mist to condense and drop back into the battery.[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY TERMINAL DESIGN
[/SIZE]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Three design types of battery terminals are used; the Top (Post) Terminal, Side Terminal, and the "L" Terminal types. The *top terminal* design is the most popular among automotive batteries. Top[/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1] post terminal batteries have tapered posts on the top of the battery. [/SIZE][/FONT][SIZE=-1]The *side terminal* design is used exclusively by General Motors, and the *"L" terminal* design is used in marine applications; both [/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]have internally threaded terminals.[/SIZE][/FONT][SIZE=-1] [/SIZE][/FONT][/FONT]





​


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY TERMINAL IDENTIFICATION
[/SIZE]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Ba[/SIZE][/FONT][SIZE=-1]ttery terminals are identified as either "*positive*" or "*negative*". Battery cases are marked with a "*+*" for the positive terminal, and a "*-*" on the negative terminal as shown below. The words "*POS*" or "*NEG*" are often used instead of the *+* or *-*. On top post terminal batteries, the positive post is slightly wider than the negative terminal post. This allow for easy identification.[/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY TERMINAL CLAMPS
[/SIZE]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Battery cable clamps are can be made of steel or lead depending on the manufacturer. In addition, they can be attached to the cable by either crimp or bolt and nut. A crimped one piece battery cable with clamp is the most common used today.[/SIZE][/FONT][/FONT]
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]




STEEL [/SIZE][/FONT]*
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]




LEAD [/FONT]*[/SIZE]​ 



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BUILT IN SPECIFIC GRAVITY INDICATOR
[/SIZE]*[SIZE=-1]Most maintenance free[/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1] batteries use a built in single ball hydrometer that measures specific gravity in one cell, which is located on the top of the battery.[/SIZE][/FONT][/FONT]








​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY HOLD DOWN / CARRIER
[/SIZE]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Battery hold downs are used to stop the battery from vibrating, moving, or spilling over while the car is in motion. Vibration will cause the battery to fail prematurely. Excessive vibration or sharp movement will cause active material to fall off the plates ruining the battery. The battery must always be secured. Additionally, a battery carrier or tray underneath the battery aids in securing the battery to the vehicle.[/SIZE][/FONT][/FONT]


 


[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]MANUFACTURER CODE / DATE CODE[/SIZE]*
[SIZE=-1]A manufacturer's code is stamped onto the battery case at time of its manufacture. This manufacturers code contains information as to the date of manufacture, type, manufacturing plant, etc. [/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]
[/SIZE][/FONT][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]A two letter code ( B0, A9, etc.) is also placed on the battery to make it easier for resellers and consumers to identify the production date. The code is on a sticker affixed to the battery or hot-stampded into the case cover along the top edge. The first letter represents the month, and the second number represents the year. The picture below shows B9, which is February 1999. Fresh batteries are always the best. Refer to the battery vendor or supplier for this information.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*STICKER
DATE CODES* 
A = January
B = February
C = March
D = April
E = May
F = June
G = July
H = August
J = September
K = October
L = November
M = December[/SIZE][/FONT] 


 


[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]DATE CODE EXCEPTIONS[/SIZE]*
[/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*DELCO* - Freedom, Voyager, and some Sears brands:
The code dates are stamped on the cover, usually near the posts. The first character represents the year (0-9) and the second shows the month (A-M, skipping I). For example, 4CN1 would stand for 1994, March. [/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]*[SIZE=-1]EXIDE[/SIZE]* -[SIZE=-1] Napa Legend, Edge, Power-Tron and Titan: The fourth or fifth character may be a letter code for the month and the following character a number code for the year (i.e. RO8F3B stands for June 1993).[/SIZE][/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY CAPACITY RATINGS[/SIZE]*
[SIZE=-1]Several battery capacity ratings have been established by the Battery Council International (BCl) that determine the current capacity of a battery. The current capacity is an indication of the battery's ability to develop and deliver high amperage current to the starter and provide reserve power to the electrical system.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]1) COLD CRANKING AMPS[/SIZE]*
[SIZE=-1]The first battery rating is the *cold cranking amps (CCA) rating*. This rating indicates the ability of a battery to deliver a specified current at low temperature. The rating is determined by the amount of current a fully charged battery can supply for 30 seconds at 0'F (- 17.8'C) without having the battery terminal voltage fall below 7.2 V. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]2) CRANKING AMPS
[/SIZE]*[SIZE=-1]The second battery rating is the *cranking amps (CA) rating* (not to be confused with COLD Cranking Amps), which is the battery's ability to deliver a cranking current at 32' F. *This CA Rating is the same test as in the CCA rating, except it is calculated at a high temperature.* A battery with a CA rating of 800 may confuse a technician who may assume it is a CCA rating number. To convert CA at 32 'F to CCA at 0 'F, divide CA by 1.25. Example: a 650 CCA rated battery has the same current capacity as a 812 CA rated battery. This apparent marketing ploy may confuse the public into thinking they are purchasing a battery which is higher in capacity than it really is.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]3) RESERVE CAPACITY [/SIZE]*
[SIZE=-1]The third battery rating, the *reserve capacity rating,* is the time in minutes a vehicle can be driven after the charging system fails. This is roughly equivalent to the conditions after the alternator fails while the vehicle is being driven at night with the headlights on. The battery alone must supply current to the headlights and the computer/ignition system. The assumed battery load is a constant discharge current of 25 A. The reserve capacity rating is the length of time a fully charged battery that is at a temperature of 80'F (26.7'C) can supply 25 A before the terminal voltage falls below 10.5 V. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]4) AMPERE HOUR[/SIZE]*
[SIZE=-1]The fourth battery rating, the *ampere-hour rating* (expressed in ampere-hours, or Ah) is the amount of current a fully charged battery can supply for 20 hours without having the terminal voltage fall below 10.5 V. This test is made at a temperature of 80'F (26.7'C). If a battery can deliver 4 A under these conditions, it is an 80-Ah battery (4 A X 20 hours = 80 Ah). [/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY GROUP SIZE [/SIZE]*
[SIZE=-1]The Battery Council International (BCI) also determines the size group number. The BCI size group number identifies a battery in terms of its width, length, height, terminal design, and other physical features. Automotive manufacturers provide a designated amount of space in the engine compartment to accommodate the battery. Battery companies build batteries of various current-capacity ratings in a variety of sizes and shapes. A replacement guide is used when replacing a battery because the battery must fit into the space provided. [/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY INFORMATION LABEL
[/SIZE]*[SIZE=-1]The capacity rating and group size information is usually located on the manufactures label. Additional information may also be provided.[/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]36 VOLT BATTERIES[/SIZE]* 
[SIZE=-1]Soon you will find 36 volt batteries on new model vehicles. With the growing number of electrical devices on vehicles, the number of wires keeps growing. The advantage of 36 volt batteries will be the high voltage allows devices to operate with lower current flow, resulting in smaller wires, lightening the vehicle weight. What kind of charging system will the 36 volt battery need? A 42 volt charging system to begin with. The higher voltage output of the alternator will result in lower current from the alternator, resulting in smaller or equivalent size alternators used today. Look for these being first on the market from Mercedes or other high end cars.[/SIZE][/FONT]




انتهى الموضوع بامر الله .


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## mohamed abouzahra (7 أغسطس 2007)

الموضوع السابع :
خدمة البطارية او صيانة البطارية .

Battery Service 
_-_-_-_-_-_-_-_-_-_-_-_-_-


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY SERVICE
[/SIZE]*[SIZE=-1]Battery services are routinely performed. These services include:[/SIZE][/FONT]

*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. Testing[/SIZE][/FONT]*



*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. Charging[/SIZE][/FONT]**[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3. Cleaning[/SIZE][/FONT]**[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]4. Jumping a dead battery[/SIZE][/FONT]**[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]5. Adding water[/SIZE][/FONT]*​


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY TESTING[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Battery testing has changed in recent years; although the three areas are basically the same, the equipment has improved.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. *Visual Inspection*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. *State of Charge*
a. Specific Gravity
b. Open Circuit Voltage[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3. *Capacity or Heavy Load Test*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* This does not include the Midtronics battery tester which has a different test procedure and will be discussed later in this module.[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]VISUAL INSPECTION [/SIZE]*
[SIZE=-1]Battery service should begin with a thorough visual inspection. This inspection may reveal simple, easily corrected problems.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1 . Check for cracks in the battery case and broken terminals. Either may allow electrolyte leakage, which requires battery replacement. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. Check for cracked or broken cables or connections. Replace, as needed. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3. Check for corrosion on terminals and dirt or acid on the case top. Clean the terminals and case top with a mixture of water and baking soda. A battery wire brush tool is needed for heavy corrosion on the terminals. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]4. Check for a loose battery hold-down or loose cable connections. Clean and tighten, as needed.[/SIZE][/FONT]







​[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]VISUAL INSPECTION - CONTINUED[/SIZE]*[/FONT][SIZE=-2]
[/SIZE][SIZE=-1]5. Check the electrolyte fluid level. The level can be viewed through the translucent plastic case or by removing the vent caps and looking directly into each cell. The proper level is 1/2" above the separators (about 1/8" below the fill ring shown below). Add distilled water if necessary. Do not overfill. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]6. Check for cloudy or discolored electrolyte caused by overcharging or vibration. This could cause high self discharge. Correct the cause and replace the battery. [/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]STATE OF CHARGE[/SIZE]*
[SIZE=-1]The state of charge of a battery can be easily check in one of two ways: [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*1) Specific Gravity Test*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*2) Open Circuit Voltage Test*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note 1:* A state of charge test is required to determine if there is sufficient charge in the battery to properly perform a capacity test (explained later). [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note 2: *The only exception to this is the MIDTRONICS Battery Tester. This new state of the art capacitance tester will be discussed later in this module.[/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]SPECIFIC GRAVITY[/SIZE]*
[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Specific gravity means exact weight. A "Hydrometer" or a "Refractometer" compares the exact weight of electrolyte with that of water. Strong electrolyte in a charged battery is heavier than weak electrolyte in a discharged battery. By weight, the electrolyte in a fully charged battery is about 36% acid and 64% water. The specific gravity of water is 1.000. The acid is 1.835 times heavier than water, so its specific gravity is 1.835. The electrolyte mixture of water and acid has a specific gravity of 1.270, usually stated as "twelve and seventy." [/SIZE][/FONT]


 



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]SPECIFIC GRAVITY [/SIZE]*[/FONT][SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]READINGS
[/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif]By measuring the specific gravity of the electrolyte, you can tell if the battery is fully charged, requires charging, or must be replaced. It can tell you if the battery is sufficiently charged for a capacity (heavy-load) test. The battery must be at least 75% charged to perform a heavy load test. (The heavy load test will be discussed later). In other words, each cell must have a specific gravity of 1.230 or higher to proceed. [/FONT][/SIZE]
[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT][/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]CELL READINGS[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]PERCENT CHARGED[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.270[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]100 % [/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.230[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]75%[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.190[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]50%[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.145[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]25%[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.100[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]0%[/FONT]*[/SIZE]​ 
[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]If the battery is less than 75% charged, it must be fully recharged before proceeding. If the battery is 75% or higher proceed to a heavy load test. A battery not sufficiently charged will fail because it is discharged. [/FONT][/SIZE]​ 



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]SPECIFIC GRAVITY [/SIZE]*[/FONT][SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]- EXCESSIVE CELL VARIATION[/FONT]*[/SIZE] [SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]READINGS
[/FONT]*[SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]Variation in specific gravity among cells cannot vary more than 0.050. The variance is the difference between the lowest cell and the highest cell. A battery must be condemned for excessive cell variation if more that 0.050. In the example below, the highest SG reading is cell #1 (shown in green) while the lowest SG reading is cell #5 (shown in blue)[/FONT][/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]; the difference is 0.070 which requires battery replacement. Cell #5 if failing.[/SIZE][/FONT][/SIZE]
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Cell #1 [/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Cell #2[/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Cell #3[/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Cell #4[/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Cell #5[/SIZE][/FONT]*
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Cell #6[/SIZE][/FONT]*
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.260[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.230[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.240[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.220[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.190[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]1.250[/FONT]*[/SIZE]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT]​[SIZE=-1][SIZE=-1][FONT=Verdana, Arial, Helvetica, sans-serif]Many factors contribute to cell variation; for example, if water was just added to that cell, the cell is then diluted with water resulting is a lower specific gravity reading. Recharging the battery would correct this false reading. In some cases if a battery that has cell variation slightly over the specification and is only about 50% charge, charging the battery at a slow rate of charge (5A) may reduce the cell variation, thus saving the battery.[/FONT][/SIZE][/SIZE]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]SPECIFIC GRAVITY [/SIZE]*[SIZE=-1]*TEST PROCEDURE HYDROMETER*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. Wear suitable eye protection.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. Remove vent caps or covers from the battery cells. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3. Squeeze the hydrometer bulb and insert the pickup tube into the cell closest to the battery's positive (+) terminal. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]4. Slowly release the bulb to draw in only enough electrolyte to cause the float to rise. Do not remove the tube from the cell. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]5. Read the specific gravity indicated on the float. Be sure the float is drifting free, not in contact with the sides of top of the barrel. Bend down to read the hydrometer at eye level. Disregard the slight curvature of liquid on the float. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]6. Record your readings and repeat the procedure for the remaining cells. [/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]ADJUSTED SPECIFIC GRAVITY [/SIZE]*[/FONT][SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]READINGS
[/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif]Temperature correction is needed because specific gravity changes with temperature[/FONT][/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]. Cold thickens the electrolyte and raises the specific gravity. Heat thins the electrolyte and lowers the specific gravity. Hydrometers are calibrated at 80'F (26.7'C). Electrolyte temperatures above or below 80'F must be adjusted. For every 10'F increment below 80'F, subtract 0.004 to the hydrometer readings, and for each 10'F increment above 80'F, add 0.004 to the readings. See the examples below.[/SIZE][/FONT]






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]SPECIFIC GRAVITY [/SIZE]*[/FONT][SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]TEST PROCEDURE
(AC Delco Battery with built- in Hydrometer)[/FONT]*[/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. Wear suitable eye protection.
2. Observe the built-in hydrometer. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Green Dot* is visible: the battery is sufficiently charged for further testing (Heavy Load Test).[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Dark Green Dot* is visible: the battery needs to be recharged before further testing.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Light or Yellow Dot* is visible: replace the battery[/SIZE][/FONT]​







​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]OPEN CIRCUIT VOLTAGE[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]A digital voltmeter must be used to check the battery's open-circuit voltage. Analog meters are not accurate and cannot be used.[/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1 . Turn on the headlamps' high beam for several minutes to remove any surface charge. 

2. Turn headlamps off, and connect the digital voltmeter across the battery terminals. 

3. Read the voltmeter. A fully charged battery will have an open-circuit voltage of 12.6 volts. On the other hand, a totally dead battery will have an open-circuit voltage of less than 12.0 volts. [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* If the battery is 12.4v or higher, proceed to heavy load test. If the battery is less than 12.4v, the battery must be fully recharged before testing. *Be sure to remove the surface charge completely*; this is the number one mistake technicians make. If need be, place a load tester on the battery and load the battery for 10 seconds at approximately 200 amps. Allow a few minutes for the battery to recover then measure the open circuit voltage. This should remove the surface charge and allow an accurate open circuit voltage measurement. (Remember: a reading of 12.4 volts or higher load test the battery, 12.3 volts or less, recharge the battery.)[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]HEAVY LOAD TEST[/SIZE]*[/FONT][SIZE=-1][/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]While a State of Charge test determines the battery's state of charge, it does not measure the battery's ability to deliver adequate cranking power. A capacity, or heavy-load test measures the battery's ability to deliver current. A battery load tester such as a Sun VAT-40 is used. (Note: the battery must be at least 75% charged before a heavy test can be performed.) [/SIZE][/SIZE][/FONT]


​


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]DETERMINE CAPACITY RATING
[/SIZE]*[SIZE=-1]The capacity rating is located on the battery label. Ratings can be expressed in CCA (Cold Cranking Amps), AH (Amp-Hour), or JIS (Japanese Industrial Standard.) JIS uses a six digit code (not shown). A conversion table is offered below that can be printed. [/SIZE][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]If no rating is found on the battery, then use the OEM battery rating found in most repair manuals.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT][/FONT]





​
*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]JIS CODE CONVERSION TABLE[/SIZE][/FONT]*
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]JIS[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]CCA[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]JIS[/FONT]*[/SIZE]
[SIZE=-1]*[FONT=Verdana, Arial, Helvetica, sans-serif]CCA[/FONT]*[/SIZE]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]26A17[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]225[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]55D26[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]348[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]26A19[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]201[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]65D26[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]413[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]28A19[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]248[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]75D26[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]490[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]32A19[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]294[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]80D26[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]582[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]26B17[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]225[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]65D31[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]389[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]28B17[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]246[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]75D31[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]447[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]32B17[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]279[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]95D31[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]622[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]28B19[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]247[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]95E41[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]512[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]34B19[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]272[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]105E41[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]577[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]36B20[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]274[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]115E41[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]651[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]38B20[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]332[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]130E41[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]799[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]46B24[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]325[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]115F51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]638[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]50B24[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]390[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]145F51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]780[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]55B24[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]433[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]150F51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]916[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]32C24[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]238[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]170F51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]1045[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]50D20[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]306[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]145G51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]754[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]55D23[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]356[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]165G51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]933[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]65D23[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]420[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]180G51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]1090[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]70D23[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]490[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]195G51[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]1146[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]75D23[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]520[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]190H52[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]924[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]48B26[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]278[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]245H52[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]1532[/SIZE][/FONT]​ 



HEAVY LOAD TEST PROCEDURE 
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. Install the load tester as shown in an earlier slide.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. Load the battery by turning the Load Increase control until the ammeter reads 3 times the amp-hour (AH) rating or one-half the cold-cranking ampere (CCA) rating. 3. Maintain the load for no more than 15 seconds, and note the voltmeter reading. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]4. If the voltmeter reading during the test is[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*9.6* volts or higher, the battery is good.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*9.5* volts or below, the battery is defective and needs replacement.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* Results will vary with temperature. Low temperatures will reduce the voltage reading, so the electrolyte should be at 70'F or above. If not, use the following conversion table:[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Voltage*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Temperature*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]9.6[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]70'F or above[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]9.5[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]60'F[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]9.4[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]50'F[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]9.3[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]40'F[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]9.1[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]30'F[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]8.9[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]20'F[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]8.7[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]10'F[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]8.5[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]0'F[/SIZE][/FONT]​ 



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]CURRENT DRAINS
[/SIZE]*[SIZE=-1]Parasitic drains are the small current drains required to operate various electrical systems, such as the clock, computer memory, or alarms, that continue to work when the car is parked and the ignition is off. All vehicles today have parasitic drains and over time will drain all batteries if not driven or charged periodically. The problem is when the parasitic drain becomes excessive, usually over 35 milliamps.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Unwanted battery drain can also be the reason why a battery keeps discharging. Unwanted battery drain can be a result of *excessive parasitic drain*, or if the top of the battery is wet or has excessive corrosion, it could create a path between the two battery posts, causing a current drain; usually 0.5 volt potential or higher will result in a battery discharge. This is called *Case Drain.*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2][/SIZE][/FONT]








[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]PARASITIC DRAIN[/SIZE]*[/FONT]
[SIZE=-1]Check for excessive battery drain or parasitic loads using an ammeter. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Make sure all electrical loads are off in the car, doors closed, and the key is out of the ignition switch . Disconnect one of the battery cables from the battery, placing an ammeter in series between the battery post and cable clamp. The current draw reading should be less than 35 milliamps. A reading higher than this (or manufacturer specifications) would indicate excessive battery drain. Something is "on", allowing current to flow running down the battery. Vehicles today typically will draw less than .020 amps (20 milliamps) of current to maintain electronic memories and circuits. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT]


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* If the battery is disconnected parasitic drains may temporarily increase. Circuits in the engine and body computers are activated and will run until internal timers runout. This reactivation period could be anywhere from a few seconds to almost 30 minutes. Whenever possible avoid disconnecting the battery while performing this test. It is possible to place one lead of the ammeter on the battery post and the other on the battery clamp, while at the same time lifting the battery clamp off the battery post. On side terminal batteries, connect the voltmeter with alligator clips and let sit until the timers run out.[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY DISCHARGE / CASE DRAIN[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Check for battery discharge (case drain) across the top of the battery using a digital voltmeter. Connect the negative (black) test lead to the battery's negative terminal post, and connect the positive (red) test lead to the top of the battery case. If the meter reads more than 0.5 volt, clean the case top using a solution of baking soda and water. Remove excess water from top of battery.[/SIZE][/FONT]







[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY CLAMP - POST RESISTANCE
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Resistance between the battery terminal post and the clamp can account for the battery not being completely recharged and is often a problem. Although it may visually look all right, oxidation of the metal or slight corrosion can cause excessive resistance at the connection, thus creating a voltage drop and lowering current flow to the starter. Battery post and clamps should be cleaned at each battery inspection. To check for excessive resistance, perform a voltage drop between the battery terminal post and the clamp (shown below) while cranking the engine. The voltage drop reading should be 0.0 volts. Any voltmeter reading higher than "zero" volts requires cleaning the connection and rechecking.[/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]MIDTRONICS BATTERY TESTER[/SIZE]*[/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Midtronics' test equipment is safe and simple to use while providing an accurate diagnosis in seconds. Midtronics battery testers are based on the measurement of battery conductance rather than a load test. Midtronics can even test a discharged battery to determine its condition. This tester is recommended by most automotive vehicle manufacturers. The 500 series model shown below not only can test the battery but the starting and charging systems as well.[/SIZE][/SIZE][/FONT]





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]MIDTRONICS OPERATION[/SIZE]*[/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[SIZE=-1]Conductance is a measurement of the battery's ability to produce current. To measure conductance, the tester creates a small signal that is sent through the battery, then measures a portion of the AC current response. Conductance is a measure of the plate surface available in the battery which determines how much power the battery can supply. As a battery ages, the plate surface can sulfate or shed active material, which adversely affects its ability to perform. In addition, conductance can be used to detect cell defects, shorts, and open circuits, which will reduce the ability of the battery to deliver current. [/SIZE][/SIZE][/FONT]




[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]MIDTRONICS BATTERY TEST PROCEDURE[/SIZE]*[/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2] [/SIZE][/FONT]*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]
[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. Connect the tester to the battery.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. Push a couple of buttons. (Enter information the unit requests, such as "in" or "out" of vehicle and rating method, such as CCA, CA, MCA, etc. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3. The automated test will take a few seconds giving accurate results.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* No load test is required and a state of charge test does not need to be done. No skill is required. Hook it up and go. Although the Midtronics is not 100% accurate, it have proven to be more reliable than human error.[/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY CHARGING [/SIZE]*[SIZE=-2]
[SIZE=-1]All battery chargers operate on the same principle: an electric current is applied to the battery to reverse the chemical action in the cells. Never connect or disconnect leads with the charger turned ON. Follow the battery charger manufacturer's instructions. DO NOT attempt to charge a battery with frozen electrolyte. When using a battery charger, always disconnect the battery ground cable first. This will minimize the possibility of damage to the alternator or electronic components in the vehicle. The battery can be considered fully charged when all cells are gassing freely and when there is no change in specific gravity readings for more than one hour. [/SIZE][/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*A slow charge is 5 or 10 amps while a fast charge is generally 15 amps or higher. A slow charge is always preferred.*[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2][/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*BATTERY CHARGER TYPES
*Battery chargers are available in two classifications: Manual and Automatic. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Automatic chargers* (typically the type consumers purchase) pulse and cycle the charge current and voltage rates. This automatic cycling rate protects the battery from damage and allows the charge rate to taper over time.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Manual chargers* (shown below), also known as wheel chargers, are preferred by automotive professionals. These charges do not cycle, but rather provide a constant non tapering charge. The constant charge rate allows the technician to accurately calculate the charge time to prevent overcharging of the battery.[/SIZE][/FONT]








[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Automatic Charger*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Manual Charger*[/SIZE][/FONT]​



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]GENERAL RULES FOR CHARGING A BATTERY[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Always leave the vent caps in place during charging. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Always follow the battery charger manufacturer's instructions. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Always charge batteries in a well ventilated area, and wear eye protection and protective clothing, such as a rubber apron and rubber gloves.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-2]Always keep sparks or flames away from the battery. (Do not smoke near a battery)[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Recharge the battery at the same rate at which it was discharged. If the discharge was slow, then charge at a slow rate; if the discharge was rapid, then charge at a higher rate. (When in doubt always use a slow charge.)[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Never charge a battery that is connected to a vehicle. Disconnect the battery and charge. Excessive voltage can damage electrical circuits on the vehicle.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Recheck specific gravity readings periodically, determine if further charging is still required.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Periodically check the battery for excessive heat by placing your hand on the side of the battery. If it is hot (125'F) to the touch, interrupt the charging (turn off) until the battery cools and lower charge rate.[/SIZE][/FONT]

​


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## mohamed abouzahra (7 أغسطس 2007)

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CHARGING PROCEDURE - AUTOMATIC CHARGER
*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Determine the type of battery... "sealed" or "accessible". If "sealed," the battery must be charged using a slow rate. (A "sealed" battery does not allow access to the cells or the addition of water or measuring specific gravity.) If "accessible," the battery may be charged at either the slow or fast rates. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Insure the charger is disconnected from the power source and/or the charger is turned off. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Connect the charger to the battery: positive cable to the positive terminal or negative cable to the negative terminal. (Insure a good connection by rocking back and forth.) [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]4. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Plug in the charger. If there is a setting switch for "regular" or "deep cycle" batteries, use regular setting for regular (accessible) batteries and sealed/gel electrolyte batteries. Use deep cycle setting for standard deep cycle batteries and maintenance free batteries. Always refer to battery charger instruction manual before using battery charger. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]5. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Periodically check the battery for excessive heat by placing your hand on the side of the battery. If it is hot (125'F) to the touch, interrupt the charging (turn off) until the battery cools. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]6.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]During the charge cycle, the charger senses the battery's state of charge and will input amps at the appropriate rate. As the battery approaches a full state of charge, the input amperage will decrease. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]7.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]After charging is complete, verify the charger is turned off and disconnected from the power source before removing charger cables. [/SIZE][/FONT]​ 


[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CHARGING PROCEDURE - MANUAL CHARGER*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]1. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Determine the type of battery... "sealed" or "accessible". If "sealed," the battery must be charged using a slow rate. (A "sealed" battery does not allow access to the cells for the addition of water or measuring specific gravity.) If "accessible," the battery may be charged at either the slow or fast rates. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]2. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Insure the charger is disconnected from the power source and/or the charger is turned off. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]3.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Connect the charger to the battery: positive cable to the positive terminal or negative cable to the negative terminal. (Insure a good connection by rocking clamp back and forth.) [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]4. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Plug-in the charger, set -the charge rate, and turn on the charger. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]5. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Periodically check the battery for excessive heat by placing your hand on the side of the battery. If it is hot 125'F) to the touch, interrupt the charging (turn off) until the battery cools. [/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]6.[/SIZE][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]After charging is complete, insure charger is turned off and disconnected from the power source before removing charger cables. [/SIZE][/FONT]​ 


[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]CHARGING RATES - MANUAL CHARGER
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The table below is used to calculate the charge rate and time of batteries of various strengths and states of charge using a manual (wheel type) charger. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Example: A battery with an RC (Reserve Capacity) rating of 80 RC and the state of charge is only 25% (specific gravity), first select the correct RC rating in the yellow column, 80 RC in our example. Now, select the charge rate (either 5 or 10 amps) under the state of charge column, 10 amps in our example. Where the two reading intersect (10 amps under 25% and 80 RC) will provide the amount of time in minutes (180) to charge the battery. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* If you are wondering where to get the RC rating of a battery that only has a CCA rating on it, refer to your battery vender for such information. It should be readily available from their product application book. If not, place battery on a low charge rate and check electrolyte specific gravity every 30 minutes until charged. [/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]STATE OF CHARGE[/SIZE]*[/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]75%[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]50%[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]25%[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]0%[/SIZE]*[/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CHARGE RATE (AMPS)*[/SIZE][/FONT]​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]5[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]10[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]5[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]10[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]5[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]10[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]5[/SIZE]*[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]10[/SIZE]*[/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*50 RC *[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]75[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]35[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]150[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]75[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]225[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]180[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]300[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]150[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*60 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]90[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]45[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]180[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]90[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]270[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]135[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]360[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]180[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*70 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]105[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]50[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]210[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]105[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]315[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]155[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]420[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]210[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*80 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]120[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]60[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]240[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]120[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]360[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]180[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]480[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]240[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*90 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]135[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]65[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]270[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]135[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]405[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]200[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]540[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]270[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*100 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]150[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]75[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]300[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]150[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]450[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]225[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]600[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]300[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*110 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]165[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]80[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]330[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]165[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]495[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]240[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]660[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]330[/SIZE][/FONT]

[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*120 RC*[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]180[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]90[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]360[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]180[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]540[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]270[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]720[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]360[/SIZE][/FONT]

*[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]BATTERY RESERVE (RC)
CAPACITY RATING
IN MINUTES[/SIZE][/FONT]*
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*CHARGE TIME IN MINUTES*[/SIZE][/FONT]





​ 



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]CHARGING RATE - OPTIMA GEL CELL BATTERY
[/SIZE]*[SIZE=-1]A Gel Cell Battery requires a shorter charge time. Optima recommends use of a voltage regulated charger set to the limits below.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Voltage:* 13.8 to 15.0 volts* Current: *10 amps maximum* Time:* 8 hours maximum
[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]*Note:* Always use a voltage regulated battery charger with limits set to the above ratings. Overcharging can cause the safety valves to open and battery gasses to escape, causing premature failure. These gasses are flammable! You cannot replace water in sealed batteries that have been overcharged. Any battery that becomes very hot or makes a hissing sound while recharging should be disconnected immediately. [/SIZE][/FONT]



[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY TERMINAL CLEANING 
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Over a period of time, sulfuric acid will corrode battery terminals, clamps, and hold-down. This corrosion adds resistance and lowers current flow to and from the battery. Corrosion can be easily cleaned with a mild solution of baking soda and water. Battery terminals and cables are routinely removed, cleaned, and reinstalled. A battery brush, which has both an external and internal brushes, is ideal for cleaning the terminal posts and the inside of clamp. [/SIZE][/FONT]​





​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY JUMPING with Booster Cables
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Jump starting a dead battery with a booster battery or battery in a car can be dangerous, so the proper sequence of connections will prevent sparks. [/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]First, connect the two positive terminals, one from the good battery and the other to the dead battery. Next connect one end of the jumper cable to the negative terminal of the booster (Good) battery. Finally connect the other end to a good ground on the engine away from the dead battery. If a spark occurs, it won't be near the battery, thus reducing the chance for explosion. If the jump starting from another vehicle, start the vehicle, running the engine at 1500 RPM for a few minutes. While the engine is running, start the dead vehicle. Never jump start a frozen battery. [/SIZE][/FONT]​




​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]BATTERY JUMPING with Booster Pack
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The portable booster pack is a lead-acid gel cell type battery. Typically capacity ranges from 250 - 1000 CCA ratings. Both consumer and professional versions are available. It contains an accessory plug and has a test button to verify its' own state of charge. Booster battery packs have proven to be a safe and effective in jump starting vehicles. To use: Connect the red booster pack cable to the positive terminal of the battery and the other cable end to a good ground on the engine away from the dead battery.[/SIZE][/FONT]​






​[FONT=Verdana, Arial, Helvetica, sans-serif]*[SIZE=-1]ADDING WATER 
[/SIZE]*[/FONT][FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]Under the rare occurrence of adding water to a battery, *use only Distilled water*. Minerals and chemicals that are commonly found in regular drinking water will react with the plate material and shorten battery life. Under normal conditions the addition of water should not be required. However, the addition of water may be necessary when the battery has been overcharged, for overcharging results in excessive evaporation of water from the electrolyte.[/SIZE][/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif][SIZE=-1]The water level should be no higher than 1/8 inch below the bottom of the vent well. To avoid permanent damage, make sure the electrolyte level never drops below the top of the plates. Also, avoid over filling, this may result in electrolyte overflow from the battery. [/SIZE][/FONT]


انتهى الموضوع ​


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## mohamed abouzahra (7 أغسطس 2007)

الدرس القادم سوف يكون عن الدينمو والمارش وبعد ذلك ندخل على الانظمة الحديثة والحساسات 
انشاء الله


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## eng_mechanic (7 أغسطس 2007)

بسم الله الرحمن الرحيم
جزاك الله كل خير اخى الفاضل على هذا المجهود العظيم
وشكرا


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## صديق المهندسين (7 أغسطس 2007)

بارك الله بيك وجزاك الله خير


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## do3a2rose (7 أغسطس 2007)

محمد الكورس دة تحفة 

وكمل 

ومش مهم حد يرد الكورس دسم وعاوز حد متخصص اوى او يكون مهتم اوى 

ولو واحد بس بيستفاد وبتاخد ثوابه


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## bader_m (7 أغسطس 2007)

بارك الله فيك وتبت خطاك


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## mohamed abouzahra (7 أغسطس 2007)

eng_mechanic قال:


> بسم الله الرحمن الرحيم
> جزاك الله كل خير اخى الفاضل على هذا المجهود العظيم
> وشكرا


 


الله يبارك فيك ياخى


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## mohamed abouzahra (7 أغسطس 2007)

صديق المهندسين قال:


> بارك الله بيك وجزاك الله خير


 
الله يبارك فيك يا بشمهندس . مشكوررر على متابعة الموضوع


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## mohamed abouzahra (7 أغسطس 2007)

do3a2rose قال:


> محمد الكورس دة تحفة
> 
> وكمل
> 
> ...


 

مشكورر جدا على ردك الجميل يا بشمهندسة . وان اشاء الله هكمل الكورس .


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## mohamed abouzahra (7 أغسطس 2007)

طايربالعجه قال:


> بارك الله فيك وتبت خطاك


 

مشكورررر جدا على ردك على الموضوع با بشمهندس . جزالك الله كل خير


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## شكري داغم عبسي (7 أغسطس 2007)

تشكر اخي مواضيع جميلة فعلا وبورك فيك


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## mohamed abouzahra (7 أغسطس 2007)

شكري داغم عبسي قال:


> تشكر اخي مواضيع جميلة فعلا وبورك فيك


 

الله يبارك فيك يا خى ومشكورررررررر


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## حسامكو العالمية (7 أغسطس 2007)

احلى مهندس واحلى موضوع واحلى ملتقى
الله يوفقك ويسدد خطاك الى الامام


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## mohamed abouzahra (8 أغسطس 2007)

حسامكو العالمية قال:


> احلى مهندس واحلى موضوع واحلى ملتقى
> الله يوفقك ويسدد خطاك الى الامام


 

مشكورررررر اخى حسامكو على ردك الجميل وان شاء الله هحاول اشوف لك طلبك ان شاء الله .


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## شكرى محمد نورى (8 أغسطس 2007)

الأخ محمد ابو زهرة .

تحية طيبة .

انجاز رائع واسطورة .

موضوع تعليم وتدريب وافي ومتكامل ومفيد جدا .

جزاك الله خير جزاء وجعلها من صالح اعمالك وتسلم ايدك .

استمر الى الأمام والله يكون بعونك على هذه الجهود التي بذلتها من اجل نشرالعلم والفائدة بين صفوف

ابناء الوطن الغالي .

تحية حب وتقدير وعرفان بالجميل لشخصكم الكريم .

البغدادي


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## mohamed abouzahra (8 أغسطس 2007)

شكرى محمد نورى قال:


> الأخ محمد ابو زهرة .
> 
> تحية طيبة .
> 
> ...


 



جزالك الله خير يا بشمهندس على ردك الرائع وانشاء الله سوف اكمل الموضوع .


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## mohamed abouzahra (8 أغسطس 2007)

نبدا انشاء الله موضوع جديد وهو عن Ignition ( الاشعال ) من البداية حتى النهاية ان شاء الله .
والعناوين الاساسية هى .
Conventional Coil Ignition - CI 
Breaker-triggered Transistorized ignition - TI-B
Transistorzed ignition with hall Generator TI-H
Transistorzed ignition with induction TI-I
Semiconductor Ignition SI
Distributor less Semi-Conductor ignition DLI

ان شاء الله وسوف نبدا الشرح .
CI
اى الاشعال التقليدى بالموبينة


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## mohamed abouzahra (9 أغسطس 2007)

فى الاول شوية فيديو عن انظمة الاشعال . هائلة .
Ignition system 

http://www.estevancomp.ca/mechanics/elec2.htm
,والله ولى التوفيق .


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## mohamed abouzahra (9 أغسطس 2007)

نبدا الموضوع ان شاء الله .
Conventional Coil Ignition - CI


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## mohamed abouzahra (9 أغسطس 2007)

The distributor is the nerve center of the mechanical ignition system and has two tasks to perform. First, it is responsible for triggering the ignition coil to generate a spark at the precise instant that it is required (which varies depending how fast the engine is turning and how much load it is under). Second, the distributor is responsible for directing that spark to the proper cylinder (which is why it is called a distributor)




The circuit that powers the ignition system is simple and straight forward. (see above) When you insert the key in the ignition switch and turn the key to the Run position, you are sending current from the battery through a wire directly to the positive (+) side of the ignition coil. Inside the coil is a series of copper windings that loop around the coil over a hundred times before exiting out the negative (-) side of the coil. From there, a wire takes this current over to the distributor and is connected to a special on/off switch, called the points. When the points are closed, this current goes directly to ground. When current flows from the ignition switch, through the windings in the coil, then to ground, it builds a strong magnetic field inside the coil.
The points are made up of a fixed contact point that is fastened to a plate inside the distributor, and a movable contact point mounted on the end of a spring loaded arm.. The movable point rides on a 4,6, or 8 lobe cam (depending on the number of cylinders in the engine) that is mounted on a rotating shaft inside the distributor. This distributor cam rotates in time with the engine, making one complete revolution for every two revolutions of the engine. As it rotates, the cam pushes the points open and closed. Every time the points open, the flow of current is interrupted through the coil, thereby collapsing the magnetic field and releasing a high voltage surge through the secondary coil windings. This voltage surge goes out the top of the coil and through the high-tension coil wire.
Now, we have the voltage necessary to fire the spark plug, but we still have to get it to the correct cylinder. The coil wire goes from the coil directly to the center of the distributor cap. Under the cap is a rotor that is mounted on top of the rotating shaft. The rotor has a metal strip on the top that is in constant contact with the center terminal of the distributor cap. It receives the high voltage surge from the coil wire and sends it to the other end of the rotor which rotates past each spark plug terminal inside the cap. As the rotor turns on the shaft, it sends the voltage to the correct spark plug wire, which in turn sends it to the spark plug. The voltage enters the spark plug at the terminal at the top and travels down the core until it reaches the tip. It then jumps across the gap at the tip of the spark plug, creating a spark suitable to ignite the fuel-air mixture inside that cylinder.
The description I just provided is the simplified version, but should be helpful to visualize the process, but we left out a few things that make up this type of ignition system. For instance, we didn't talk about the condenser that is connected to the points, nor did we talk about the system to advance the timing. Let's take a look at each section and explore it in more detail.
*The ignition switch.
*There are two separate circuits that go from the ignition switch to the coil. One circuit runs through a resistor in order to step down the voltage about 15% in order to protect the points from premature wear. The other circuit sends full battery voltage to the coil. The only time this circuit is used is during cranking. Since the starter draws a considerable amount of current to crank the engine, additional voltage is needed to power the coil. So when the key is turned to the spring-loaded start position, full battery voltage is used. As soon as the engine is running, the driver releases the key to the run position which directs current through the primary resistor to the coil.
On some vehicles, the primary resistor is mounted on the firewall and is easy to replace if it fails. On other vehicles, most notably vehicles manufactured by GM, the primary resistor is a special resistor wire and is bundled in the wiring harness with other wires, making it more difficult to replace, but also more durable.
*The Distributor
*When you remove the distributor cap from the top of the distributor, you will see the points and condenser. The condenser is a simple capacitor that can store a small amount of current. When the points begin to open, the current flowing through the points looks for an alternative path to ground. If the condenser were not there, it would try to jump across the gap of the points as they begin to open. If this were allowed to happen, the points would quickly burn up and you would hear heavy static on the car radio. To prevent this, the condenser acts like a path to ground. It really is not, but by the time the condenser is saturated, the points are too far apart for the small amount of voltage to jump across the wide point gap. Since the arcing across the opening points is eliminated, the points last longer and there is no static on the radio from point arcing.
The points require periodic adjustments in order to keep the engine running at peek efficiency. This is because there is a rubbing block on the points that is in contact with the cam and this rubbing block wears out over time changing the point gap. There are two ways that the points can be measured to see if they need an adjustment. One way is by measuring the gap between the open points when the rubbing block is on the high point of the cam. The other way is by measuring the dwell electrically. The dwell is the amount, in degrees of cam rotation, that the points stay closed.
On some vehicles, points are adjusted with the engine off and the distributor cap removed. A mechanic will loosen the fixed point and move it slightly, then retighten it in the correct position using a feeler gauge to measure the gap. On other vehicles, most notably GM cars, there is a window in the distributor where a mechanic can insert a tool and adjust the points using a dwell meter while the engine is running. Measuring dwell is much more accurate than setting the points with a feeler gauge.
Points have a life expectancy of about 10,000 miles at which time they have to be replaced. This is done during a routine major tune up. During the tune up, points, condenser, and the spark plugs are replaced, the timing is set and the carburetor is adjusted. In some cases, to keep the engine running efficiently, a minor tune up would be performed at 5,000 mile increments to adjust the points and reset the timing.
*Ignition Coil
*



The ignition coil is nothing more that an electrical transformer. It contains both primary and secondary winding circuits. The coil primary winding contains 100 to 150 turns of heavy copper wire. This wire must be insulated so that the voltage does not jump from loop to loop, shorting it out. If this happened, it could not create the primary magnetic field that is required. The primary circuit wire goes into the coil through the positive terminal, loops around the primary windings, then exits through the negative terminal. 
The coil secondary winding circuit contains 15,000 to 30,000 turns of fine copper wire, which also must be insulated from each other. The secondary windings sit inside the loops of the primary windings. To further increase the coils magnetic field the windings are wrapped around a soft iron core. To withstand the heat of the current flow, the coil is filled with oil which helps keep it cool. 
The ignition coil is the heart of the ignition system. As current flows through the coil a strong magnetic field is built up. When the current is shut off, the collapse of this magnetic field to the secondary windings induces a high voltage which is released through the large center terminal. This voltage is then directed to the spark plugs through the distributor.
*Ignition Timing
*The timing is set by loosening a hold-down screw and rotating the body of the distributor. Since the spark is triggered at the exact instant that the points begin to open, rotating the distributor body (which the points are mounted on) will change the relationship between the position of the points and the position of the distributor cam, which is on the shaft that is geared to the engine rotation.
While setting the initial, or base timing is important, for an engine to run properly, the timing needs to change depending on the speed of the engine and the load that it is under. If we can move the plate that the points are mounted on, or we could change the position of the distributor cam in relation to the gear that drives it, we can alter the timing dynamically to suit the needs of the engine.
*Why do we need the timing to advance when the engine runs faster?
*When the spark plug fires in the combustion chamber, it ignites whatever fuel and air mixture is present at the tip of the spark plug. The fuel that surrounds the tip is ignited by the burning that was started by the spark plug, not by the spark itself. That flame front continues to expand outward at a specific speed that is always the same, regardless of engine speed. It does not begin to push the piston down until it fills the combustion chamber and has no where else to go. In order to maximize the amount of power generated, the spark plug must fire before the piston reaches the top of the cylinder so that the burning fuel is ready to push the piston down as soon as it is at the top of its travel. The faster the engine is spinning, the earlier we have to fire the plug to produce maximum power.
*There are two mechanisms that allow the timing to change: Centrifugal Advance and Vacuum Advance.*
*Centrifugal Advance* changes the timing in relation to the speed (RPM) of the engine. It uses a pair of weights that are connected to the spinning distributor shaft. These weights are hinged on one side to the lower part of the shaft and connected by a linkage to the upper shaft where the distributor cam is. The weights are held close to the shaft be a pair of springs. As the shaft spins faster, the weights are pulled out by centrifugal force against the spring pressure. The faster the shaft spins, the more they are pulled out. When the weights move out, it changes the alignment between the lower and upper shaft, causing the timing to advance.
*Vacuum Advance* works by changing the position of the points in relationship to the distributor body. An engine produces vacuum while it is running with the throttle closed. In other words, your foot is off the gas pedal. In this configuration, there is very little fuel and air in the combustion chamber.
Vacuum advance uses a vacuum diaphragm connected to a link that can move the plate that the points are mounted on. By sending engine vacuum to the vacuum advance diaphragm, timing is advanced. On older cars, the vacuum that is used is port vacuum, which is just above the throttle plate. With this setup, there is no vacuum present at the vacuum advance diaphragm while the throttle is closed. When the throttle is cracked opened, vacuum is sent to the vacuum advance, advancing the timing. 
On early emission controlled vehicles, manifold vacuum was used so that vacuum was present at the vacuum advance at idle in order to provide a longer burn time for the lean fuel mixtures on those engines. When the throttle was opened, vacuum was reduced causing the timing to retard slightly. This was necessary because as the throttle opened, more fuel was added to the mixture reducing the need for excessive advance. Many of these early emission controlled cars had a vacuum advance with electrical components built into the advance unit to modify the timing under certain conditions.
Both Vacuum and Centrifugal advance systems worked together to extract the maximum efficiency from the engine. If either system was not functioning properly, both performance and fuel economy would suffer. Once computer controls were able to directly control the engine's timing, vacuum and centrifugal advance mechanisms were no longer necessary and were eliminated. 
*



Ignition Wires
*These cables are designed to handle 20,000 to more than 50,000 volts, enough voltage to toss you across the room if you were to be exposed to it. The job of the spark plug wires is to get that enormous power to the spark plug without leaking out. Spark plug wires have to endure the heat of a running engine as well as the extreme changes in the weather. In order to do their job, spark plug wires are fairly thick, with most of that thickness devoted to insulation with a very thin conductor running down the center. Eventually, the insulation will succumb to the elements and the heat of the engine and begins to harden, crack, dry out, or otherwise break down. When that happens, they will not be able to deliver the necessary voltage to the spark plug and a misfire will occur. That is what is meant by "Not running on all cylinders". To correct this problem, the spark plug wires would have to be replaced.
Spark plug wires are routed around the engine very carefully. Plastic clips are often used to keep the wires separated so that they do not touch together. This is not always necessary, especially when the wires are new, but as they age, they can begin to leak and crossfire on damp days causing hard starting or a rough running engine.




Spark plug wires go from the distributor cap to the spark plugs in a very specific order. This is called the "firing order" and is part of the engine design. Each spark plug must only fire at the end of the compression stroke. Each cylinder has a compression stroke at a different time, so it is important for the individual spark plug wire to be routed to the correct cylinder. 
For instance, a popular V8 engine firing order is 1, 8, 4, 3, 6, 5, 7, 2. The cylinders are numbered from the front to the rear with cylinder #1 on the front-left of the engine. So the cylinders on the left side of the engine are numbered 1, 3, 5, 7 while the right side are numbered 2, 4, 6, 8. On some engines, the right bank is 1, 2, 3, 4 while the left bank is 5, 6, 7, 8. A repair manual will tell you the correct firing order and cylinder layout for a particular engine.
The next thing we need to know is what direction the distributor is rotating in, clockwise or counter-clockwise, and which terminal on the distributor cap that #1 cylinder is located. Once we have this information, we can begin routing the spark plug wires.
If the wires are installed incorrectly, the engine may backfire, or at the very least, not run on all cylinders. It is very important that the wires are installed correctly.
*Spark Plugs



*The ignition system's sole reason for being is to service the spark plug. It must provide sufficient voltage to jump the gap at the tip of the spark plug and do it at the exact right time, reliably on the order of thousands of times per minute for each spark plug in the engine.
The modern spark plug is designed to last many thousands of miles before it requires replacement. These electrical wonders come in many configurations and heat ranges to work properly in a given engine.
The heat range of a spark plug dictates whether it will be hot enough to burn off any residue that collects on the tip, but not so hot that it will cause pre-ignition in the engine. Pre-ignition is caused when a spark plug is so hot, that it begins to glow and ignite the fuel-air mixture prematurely, before the spark. Most spark plugs contain a resistor to suppress radio interference. The gap on a spark plug is also important and must be set before the spark plug is installed in the engine. If the gap is too wide, there may not be enough voltage to jump the gap, causing a misfire. If the gap is too small, the spark may be inadequate to ignite a lean fuel-air mixture, also causing a misfire.​


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## mohamed abouzahra (9 أغسطس 2007)

الى عايز شرح عربى ان شاء الله موجود .


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## mohamed abouzahra (10 أغسطس 2007)

ان شاء الله سوف اقوم بوضع الموضوع الجديد وهو 
Ti-b


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## شكرى محمد نورى (10 أغسطس 2007)

الأخ محمد ابو زهرة .

تحية طيبة .


تسلم ايدك وما قصرت .

اللهم اجعل له في كل خطوة سلامة وغفر له ولوالده .

برنامج تدريبي رائع ومثمر ان الله .

ويفضل بالعربي لأن اسلوبك جميل وسلس للغاية .

تمنياتي لك بالتوفيق .

البغدادي .


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## محمد حسن نصر (10 أغسطس 2007)

شكرا ليك
الموضوع ممتاز 
وزي ما اتعودنا مستنيين منك المزيد


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## شرشر (10 أغسطس 2007)

جزاك الله كل خير علي هذا المجهود
وبارك الله فيك.


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## mohamed abouzahra (10 أغسطس 2007)

شكرى محمد نورى قال:


> الأخ محمد ابو زهرة .
> 
> تحية طيبة .
> 
> ...


 


جزاك الله خير 
على درك الجميل وان شاء الله هكمل المشوار .


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## mohamed abouzahra (10 أغسطس 2007)

محمد حسن نصر قال:


> شكرا ليك
> الموضوع ممتاز
> وزي ما اتعودنا مستنيين منك المزيد


 


جزاك الله خير يا بشمهندس ان شاء الله هيكون فى المزيد


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## mohamed abouzahra (10 أغسطس 2007)

شرشر قال:


> جزاك الله كل خير علي هذا المجهود
> وبارك الله فيك.


 


مشكوررر يا جميل


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## mohamed abouzahra (10 أغسطس 2007)

ونبدا الاشعال بالترنزسوستر TI-B


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## mohamed abouzahra (10 أغسطس 2007)

ان شاء الله بعد نهاية الموضوع سوف اقوم بشرح باللغة العربية .


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## mohamed abouzahra (12 أغسطس 2007)

نبدا الموضوع


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## mohamed abouzahra (12 أغسطس 2007)

سوف اقوم ان شاء الله شرح منظمة الاشعال التقليدية باللغة العربية .
نبدا الموضوع


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## شكرى محمد نورى (12 أغسطس 2007)

على بركة الله .

البغدادي


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## AbuMaha (13 أغسطس 2007)

موضوع مميز بصراحه


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## mohamed abouzahra (13 أغسطس 2007)

AbuMaha قال:


> موضوع مميز بصراحه


 

باراك الله فيك يا خى


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## mohamed abouzahra (13 أغسطس 2007)

انا اسف ان كانت الصور مش واضحة اوى بس اانا مصورها بالتلفون 
الشرح عربى وانجليزى .


When the system is operating , voltage from the battery (1) flows through the starter/ignition switch (2) and to terminal 15 on the ignition coil (3) , when the contact breaker (6) is closed , the current flow through the primary winding of the ignition coil to ground . this builds up a magnetic filed in the ignition coil , thus storing the ignition energy . the current rise is exponential owing to the inductance and the primary resistance of the primary winding . the charging time is determined by the actuates the contact breaker via the cam follower . at the end of the dwell period , the ignition – distributor cam opens the ignition contact and thus interrupts the coil current .



عندما يتم تشغيل الدائرة . ياتى الفولت من البطارية (1) ثم الى مفتاح (2) عندما يكون الابلاتين (6) مغلق يمر التيار من خلال الملف الابتدائى ثم الى الاراضى .
وفى نفس الوقت يتم بناء مجال مغناطيسى فى ملف الاشعال عندما يتحرك كامة الابلاتين تعمل على فتح الابلاتين وبحدوث ذلك يحدث انهيار فى المجال ومنها بتكون قوة دافعة كهربية حثية فى الملف الثانوى 
وهو يبلغ حوالى من 15000 الى 24000 ويكون اكثر فى الموديلات الحديثة .
ووظيفة المكثف هنا هو الحفاظ على الابلاتين من التلف اثناء فتح وقفل الدائرة .


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## mohamed abouzahra (13 أغسطس 2007)

سوف اقوم ان شاء الله بشرح اجزاء دائرة الاشعال .

1. ملف الاشعال ( الموبينة ) ignition coil 










وهو يقوم برفع التيار القادم من البطارية 12 فولت الى حوالى 15000-24000 فولت . وذلك بمعاونة قاطع التلامس ( الابلاتين ) والمكثف بالموزع .

ويتكون من التالى :
1. قلب مصنوع من شرائح معزولة من الصلب الكهربى لتقليل فقد التيارات الدوامية .
2. أنبوبة عازلة من الكرتون حول القلب .
3. يلف حول الانبوبة العازلة الملف الثانوى من سلك معزول رفيع وعدد لفات كثير تصل الى 20-25 الف لفة 
4. يحاط الملف الثانوى بانبوبة كرتون اخرى عازلة لعزلة عن الملف الابتدائى .
5 . يلف حول الانبوبة الاخيرة الملف الابتدائى من سلك ذو قطر كبير وعدد لفات صغيرة تصل الى 300 -400 لف .


ويلاحظ ان الملف الثانوى لة طرفان , يتصل احداهما بكابل الجهد العالى المتجة للموزع ويتصل الطرف الاخر بالملف الابتدائى داخل الملف .
بينما يتصل الملف الابتدائى من احد طرفية بمصدر التيار بغطاء الملف والطرف الاخر يتصل بقاطع الاتصال ( الابلاتين ) 

وتملا بعض الملفات من الداخل بزيت محولات نقى للتبريد حيث تنخفض كفاءة الملف مع ارتفاع درجة الحرارة .

6. غطاء للملف من البكالايت مزود بفتحات لاطراف التوصيل الكهربى 
7. مقاومة توالى وتكون مركبة بداخل الملف او علية او بعيدة عنة وتصنع من سلك كروم وهى تقوم بحماية الملف الابتدائى من التسخين الزائد والناشى من طول فترة غلق الابلاتين النسبية فى السرعات البطيئة وتعمل ايضا على معادلة اى انخفاض فى جهد الملف الثانوى والذى يوثر على قوة الشرارة .


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## mohamed abouzahra (13 أغسطس 2007)

2. موزع الشرر ( الاسبراتير ) Distributor











يتلخص عملة اساسا فى تنظيم توقيت اشعال الشرارة على حسب ترتيب الحريق للمحرك.

وهو يتكون من الاتى :

1. غطاء موزع الشرر Distributor Cap











بعد الصور التوضيحية نبدا الموضوع .


ويصنع الغطاء من الفيبر او البكالايت ويثبت فى جسم الاسبراتير بواسطة قفزان ويوجد بة فى لو المحرك 4 اسطوانات يوجد بة 5 فتحات .
4 لشمعات الاشعال لكل اسطوانة وواحدة تاتى من الملف الثانوى ويسمى كابل الجهد العالى .


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## mohamed abouzahra (13 أغسطس 2007)

2. قاطع التلامس ( الابلاتين ) Contact Breaker







وظيفتة :
عند تلامس الابلاتين يمر تيار الملف الابتدائى ثم يصل الى الارضى .
وعندما يفتح بواسطة الكامة يحدث انهيار للتيار المار وبذلك يستنتج تيار جهد على فى الملف الثانوى .
وتنصنع نقاط التلامس لة من التنجستين او من سبيكة البلاتينيوم والاريديوم وذلك لتحمل الثغرات الهوائية للتيار.


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## mohamed abouzahra (13 أغسطس 2007)

فى مشكلة فى الصور مش عارف اتعامل معها ازاى


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## mohamed abouzahra (13 أغسطس 2007)




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## mohamed abouzahra (13 أغسطس 2007)

3. المكثف : Capacitor or condenser 









وظيفتة :

1. تخزين التيار الكهربى اثناء فتح الابلاتين وبذلك فانة يحمى نقاط التلامس من التلف .
2. اعادة تفريغ هذا التيار فى حالة اتصال نقاط الاتصال ويؤدى الى زيادة التيار التاثيرى .

وعند تلف المكثف يؤدى الى سرعة تلف الابلاتين وضعف ايضا قوة الشرارة .


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## شكرى محمد نورى (13 أغسطس 2007)

ماشاء الله وعاشت ايدك .
الله يكرمك .

البغدادي .


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## حسامكو العالمية (13 أغسطس 2007)

والله اشي مو طبيعي 
بس ممكن تعطينا الملف Pdfلتنزيله والتمكن من قرائته كله حيث لا تفتح بعض الصور
او ارسلها ل*****ات الذين يطلبون
الف شكر يا باشا
احلى بشمهندس


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## mohamed abouzahra (14 أغسطس 2007)

شرح افضل من الى فات


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## mohamed abouzahra (14 أغسطس 2007)

لدى مشكلة ازاى ارفع الصورة من على جهاز الى المنتدى كل ما ارفعها ياتى رموز ولا يوجد صورة


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## mohamed abouzahra (15 أغسطس 2007)

*الجزء الثانى من البرنامج التدريبى ( كورس كهرباء السيارات كامل Pdf )*

بسم الله الرحمن الرحيم ​ 
لقد قمت ووفقنى الله فى رفع كورس متكامل فى كهرباء السيارات 
من البداية حتى الاحتراف .

الملفات مساحتها 10.6 ميجا 

وباسورد الملف هو abouzahra

Password : abouzahra

رابط التحميل بالمرفقات . ان شاء الله ينال اعجابكم .

:1: :1: :1:​


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## جاسر (15 أغسطس 2007)

السلام عليكم ورحمة الله وبركاته,,

أخي الفاضل الموقع محجوب ...

مواقع بديلة وممتازة

zupload.com
mediafire.com
mihd.net
zshare.com

جميعها ممتازة ... بارك الله في جهدك


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## mohamed abouzahra (15 أغسطس 2007)

اخر المشرف جاسر رابط التحميل شغال 
بس ان شاء الله هحاول رفع على موقع اخر .


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## mohamed abouzahra (15 أغسطس 2007)

هذا دليل كلامى .


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## mohamed abouzahra (16 أغسطس 2007)

ان شاء الله 
قريب هيكون فى كورس عن AT 
and Injection


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## جاسر (16 أغسطس 2007)

السلام عليكم ورحمة الله وبركاته,,

أخي الفاضل .. نعم الرابط شغال عندك .. ولكن اخوانك في السعودية 
- محجوب - عندهم هذا الموقع 

وفقك الله لما يحب


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## م المصري (16 أغسطس 2007)

تسلم ايدك يا اخي ,,,,,


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## mohamed abouzahra (16 أغسطس 2007)

ان شاء الله هر فعها على موقع اخر . ان شاء الله


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## حسامكو العالمية (19 أغسطس 2007)

دايما كبير ورافع الراس


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## سالم حسين وادي (20 أغسطس 2007)

الاخ الفاضل جزاك الله خيرا اذا امكن ان تضع رابط الكورس الاول لاني لم اجده و شكرا مرة ثانية على موضوعك القيم.


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## mohamed abouzahra (20 أغسطس 2007)

سالم حسين وادي قال:


> الاخ الفاضل جزاك الله خيرا اذا امكن ان تضع رابط الكورس الاول لاني لم اجده و شكرا مرة ثانية على موضوعك القيم.


 

اخى العزيز سالم 
حضرتك لسة جديد فى المنتدى . يوجد فى اخر الموضوع مكان بة ( المرفقات ) يتم الضغط عليها اذا تجد ملف بة عنوان التحميل وان شاء الله هيشتغل معاك كويس 
والكورس فوق الممتاز لمتخصصى السيارات فقط ؟


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## elssakka (20 أغسطس 2007)

mashkooooooooooooooooooooor


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## elssakka (20 أغسطس 2007)

mashkooooooooooooooor


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## elssakka (20 أغسطس 2007)

*iwan_vc**************

mashkoooooooooooor


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## mohamed abouzahra (20 أغسطس 2007)

AboAyoy77 قال:


> تسلم ايدك يا اخي ,,,,,


 

بارك الله فيك


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## غسان التكريتي (21 أغسطس 2007)

شكرا يا متميز بارك الله فيك


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## سالم حسين وادي (21 أغسطس 2007)

يا سيدي الفاضل شكرا على ردك السريع , كل ما ذكرته اعلمه جيدا و قد حملت الكورس و اشتغل تمام و لكنك ذكرت انه الجزء الثاني من البرنامج التدريبي و انا اقصد عدم معرفتي برابط الجزء الاول لو تتكرم و تضع الرابط للجزء الاول و بارك الله في جهودك.


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## mohamed abouzahra (21 أغسطس 2007)

سالم حسين وادي قال:


> يا سيدي الفاضل شكرا على ردك السريع , كل ما ذكرته اعلمه جيدا و قد حملت الكورس و اشتغل تمام و لكنك ذكرت انه الجزء الثاني من البرنامج التدريبي و انا اقصد عدم معرفتي برابط الجزء الاول لو تتكرم و تضع الرابط للجزء الاول و بارك الله في جهودك.


 
اخى العزيز الجزء الاول من البرنامج التدريبى كان شرح وليس روابط تحميل وموجود فى هذا الرابط

http://www.arab-eng.org/vb/showthread.php?t=61850

وان شاء الله تعم الفائدة لو احتجت اى شى ان شاء الله انا موجود لو فى مقدرتى انى اساعدك .


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## شكرى محمد نورى (22 أغسطس 2007)

الأخ محمد ابو زهرة .

جزاك الله خير .

شكرا لردك ومتابعة مواضيعك .

البغدادي .


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## سالم حسين وادي (23 أغسطس 2007)

اشكرك اخي الفاضل و كثر الله من امثالك شكرا مرة اخرى


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## سالم حسين وادي (24 أغسطس 2007)

بارك الله فيك يا استاذ و نريد منك الاستمرار بالعطاء


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## شريف بحر (24 أغسطس 2007)

الله ينور ياستاذ


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## mohamed abouzahra (24 أغسطس 2007)

سالم حسين وادي قال:


> بارك الله فيك يا استاذ و نريد منك الاستمرار بالعطاء


 
شكرا والله يكرمك


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## mohamed abouzahra (24 أغسطس 2007)

سالم حسين وادي قال:


> اشكرك اخي الفاضل و كثر الله من امثالك شكرا مرة اخرى


 
شكرا اخى الفاضل .


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## ابواسعد (25 أغسطس 2007)

شكرا اخي الله يزيد الاشخاص امثالك


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## ماركو (5 سبتمبر 2007)

شكرا على هذه المشركات النافعة و المهمة 
وبالله التوفيق


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## wdawash (5 سبتمبر 2007)

*ألف شكر*

جزاك الله خيرا كثيرا


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## hamadawa (5 سبتمبر 2007)

جزاك الله خيرا اخي العزيز علي هذا الموضوع الرائع
ولكن هل من الممكن ان تضعة في ملف واحد ويتم تحميله كرابط حتي يعتبر كمرجع رائع و مبسط


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## proeng86 (7 سبتمبر 2007)

جزاك الله خيرا


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## مهندس نورس (7 سبتمبر 2007)

كل من يعمل خيرا
خيرا يرى .


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## محمد فريد فتحي (18 أكتوبر 2007)

شكرا جزيلا فعلا موضوع شيق:59:


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## hmhegypt86 (7 ديسمبر 2007)

جزاكي الله خيرا


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## محمد فريد فتحي (7 ديسمبر 2007)

بجد ماشاء الله عليك 
:5:


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## mostafa4b (9 ديسمبر 2007)

مشكوور أخـــى العزيـز غلى هذا المجهود الرائع 
وجعله الله فى ميزان حسناتك


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## بحار العلم (10 يناير 2008)

الله ينور وجزاك الله كل خير


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## الاوسط (10 يناير 2008)

جزاك الله كل خير علي هذا المجهود
والله لا يحرمك الاجر


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## عمر محمد3 (11 يناير 2008)

مجهود يستحق الشكر والثناء
بارك الله فيك ولك وعليك ونفعنا الله واياك


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## مصطفى ملازم (18 فبراير 2008)

جزاك الله كل خير علي هذا المجهود


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## عمع05000 (25 نوفمبر 2008)

يبدو أنك نسيت ان تشير إلى المصدر الحقيقي لهذا الدرس


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## سلامي لكم (25 نوفمبر 2008)

ما شاء الله والله مجهود رائع ومفيد الله يحفظك


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## العقاب الهرم (27 نوفمبر 2008)

thaaaaaaaaaaaaaaaaaaaaaaaanks alot


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## ابراهيم فريد (3 ديسمبر 2008)

الرابط بتاع كتاب الكهربا مش شغال من فضلك اعمل ايه
وشكرا جزيلا على هذا المجهود الرائع 
ويا ريت يكون عندك اى حاجة تفيدنا فى التشخيص لاى شىء فى الكهرباء او الميكانيكا وخصوصا السيارات الحديثة
ويا ريت بقية الدورة التدريبية
وشكرا مرة اخرى على هذا المجهود الرائع


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## محمد الشنواني (4 ديسمبر 2008)

بارك الله فيك


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## محمد سلامه الراضى (5 ديسمبر 2008)

تمام تمام تمام شرح تمام تمام تمام ربنا يزيدك


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## بوحصة (18 يناير 2009)

ا*لسلام عليكم ورحمة الله وبركاته*
*أستاذي العزيز mohamed abouzahra*
*شكراً لك على هذه المادة العلمية الأكثر من جيدة والمفيدة لذا*
* آمل من شخصك الكريم إكمال الدورة لكي أستفيد منها في مشروعي هذا الفصل حيث أني أعمل مشروع على مكينة أربع سلندر بعنوان *
*(*
*an experimental Investigation on the performance of LPG spark Ignition engine) *

*وأسأل الله أن لا يحرمك الأجر والثواب .*


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## ك ام (20 يناير 2009)

لك منى التحية والشكر على هذا العمل الممتاز ونرجو منك المزيد


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## safa aldin (30 يناير 2009)

بارك الله فيك


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## mnci (13 فبراير 2009)

انت اخ اكثر من ممتاز
*مواضيع هندسية ,المهندس, الهندسة ,تحميل كتب هندسية مجانية
http://carsnology.blogspot.com/
Engineering topics*​


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## الدرع الأخضر (13 فبراير 2009)

مشكور لكن لو كان بالعربي


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## iraqmoon (4 يوليو 2009)

lthanksssssssssssssssssssssssssssssssssssssssssssss


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## معتز المهندس (5 يوليو 2009)

مشكوووووووووووووووووووورررررررررررررررر


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## اسامة القاسى (5 يوليو 2009)

" جزاك الله خيرا على المعلومات النافعه "


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## م محمد حمدى السيد (9 يوليو 2009)

thanksssssssssssssssssssssssssssss


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## aymanstarnet (4 أكتوبر 2009)

*بارك الله فيك اخى 
وجزاك الله خيرا*​


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## sailara (9 أكتوبر 2009)

اخي الكريم الموضوع جيد وهام ولاكن هل يمكن ان يكون باللغة الفر نسية او العربية


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## ali_godfather (17 أكتوبر 2009)

شكرا على هذا البرنامج الشامل -- واعتقد هناك تكملة ولديكم المزيد !

تحياتي


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## م/عماد (22 أكتوبر 2009)

أنا سعيد قوى بهذا القسم الجديد والف مبروك


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## الحاتم (22 أكتوبر 2009)

جزاك الله خيرا


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## eng_mahmoud emam (26 أكتوبر 2009)

موضوع أكثر من رائع شكرا


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## moh_haredy7 (16 نوفمبر 2009)

مشكوووووووووووووووووور اخى على المجهود الرائع


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## العقرب2003 (17 يناير 2010)

*شكرا يا اخي وبارك الله فيك*​


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## ابوعبادة (25 يناير 2010)

مجهود أكثر من رائع بارك الله في جهودك الطيبة وفقك الله الى ما يحب ويرضى


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## محمد السيد سرور (27 يناير 2010)

السلام عليكم 
سيارتى لادا 2210 روسى :68: ارجو افادتى باكبر قدر من المعلومات عن صيانتها و يا ريت السوفت بتاع الكمبيوتر بتاعها :11:


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## مهندسه مخربة (27 يناير 2010)

جزاك الله خير


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## sami20 (28 يناير 2010)

ياخى اتمنى من الله يديك على كل حرف الف حسنة ان شاءالله
ولى كل من اطلع على الموضوع.
وكل المسلمين .
آمين.


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## خبير الاردن (26 أبريل 2010)

مشكووووووووووووور


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## سنيوريتا أناااا (11 نوفمبر 2010)

سنيوريتا انا مرت من هنا


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## steelbars77 (25 ديسمبر 2010)

ان الله فى عون العبد ما دام العبد فى عون اخيه


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## وليد العتر (26 ديسمبر 2010)

مشكور على هذا البرنامج التدريبي القيم ونحن ننتظر البقية بارك الله فيك


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## ramadan ibrahim (27 ديسمبر 2010)

a;vhhhhhhhhhh


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## bassamnh (2 يناير 2011)

شكرا موضوع جيد


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## محمد الالهام (27 يناير 2011)

شكر الله لك فبامثالك تعتلي الهامات "" ولا آحرمناء الله من ما أفادك فهل لناء بالمزيد ولكم التحااااااااياء


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## saad_srs (27 يناير 2011)

مشكورررررررررررررررررررر
جزاك الله خيرا


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## صالح السكيكدي (5 يوليو 2011)

مجهود كبير بارك الله فيك


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## momoeng (5 أكتوبر 2013)

جميل الموضوع وميسر ومفسر وجزاك الله خيرا


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## hamoo4ever (7 أبريل 2014)

الف الف شكر مجهود رائع ومعلومات مفيده الله يجزاكم الخير


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## الفاتح مطر (30 سبتمبر 2015)

تسلم


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## abdelrahim (5 نوفمبر 2015)

بارك الله فيك


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## حمدكوم (7 ديسمبر 2015)

شكرا على المعلومات القيمة ولكن
حبذا لو كانت بالعربي


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