Download Battery is the most important part in electric circuit in the car . It is the

Electric circuit
in the car
Under supervision
Of
Prof. DR/ Saad Abd El
Hamid
1- Ibrahim Atef Mohamed
2- Ahmed Atef El sayed
3- Mohamed Ahmed Abd El Mawgood
4- Hany Ahmed Ibrahim
Battery is the most important part in
electric circuit in the car .
It is the part which supplies electricity to
indicator and generator .
If more ampere-hours are required, two (or more)
new and identical 12-volt batteries can be
connected in parallel. If you connect two 12-volt
batteries in parallel, and they are identical in type,
age and capacity, you can potentially double you
original capacity. If you connect two that are not
the same type, you will either overcharge the
smaller of the two, or you will undercharge the
larger of the two.
The recommended parallel and series connections are as follows:
[Source: Interstate Batteries]
•
Connected this way the batteries will discharge and recharge
equally. When connecting in series or parallel and to prevent
recharging problems, do NOT mix old and new batteries or ones
with different types.
There are six types of battery terminals-SAE Post, GM Side, "L", •
Stud, combination SAE and Stud, and combination S.A.E Post and
GM Side. For automotive applications, the SAE Post is the most
popular, followed by GM Side, then the combination "dual" SAE Post
and GM Side. "L" terminal is used on some European cars,
motorcycles, lawn and garden equipment, snowmobiles, and other
light duty vehicles. Stud terminals are used on heavy duty and deep
cycle batteries. The positive SAE Post terminal in slightly larger (by
1/16") than the negative one. Terminal locations and polarity will
vary.
•
Alternator
The alternator is an important part of the engine
because it perpetuates the reproduction of power. The
battery supplies the initial boost the engine needs to
start the vehicle. The alternator takes over and
replaces the power used in the battery by the starting
of the engine.
alternator is rotated by a drive belt driven by the
vehicles engine while it is running. Electrical
voltage and amperage are generated to
recharge the battery and supply voltage to the
electrical system of the car. The alternator is
held in place with mounting bolts. There is a
main electrical wire on the rear of the alternator
that supplies voltage to a main voltage junction
box. If your alternator is not charging properly,
your battery will slowly drain down from
operating all the electrical systems in your car
and stop the car from running.
Common Problems and
Solutions
When jump-started a severely discharged battery can
cause the alternator to overload and internally fail. If this
occurs replace or charge the battery before replacing the
alternator. This will help prevent a second alternator
failure. Most vehicles use a multi-ribbed belt connected
to the engine to rotate the armature inside the
alternator. If the belt fails it should be replaced
immediately. Belt tension should be taught. If it isn't,
check the belt tensioner, it may need to be replaced or
the incorrect size belt may have been installed. Either of
these conditions can cause the vehicle to stall and not
restart.
Distributor Cap and Rotor
The distributor cap and rotor are two essential pieces that
distribute electrical current to the spark plugs. The
distributor cap connects to the spark plugs directly using
a spark plug wire. The number of plug wires connected
depends on the amount of spark plugs that are in the
engine. For example, an eight cylinder engine will have
eight plug wires.
The rotor is designed to spin inside of the
distributor cap, just missing the terminals inside
the cap. A worn or damaged rotor can cause
your vehicle to run rough, or even stall
completely. The rotor is rotating at the same
speed as the camshaft which also happens to be
1/2 the speed of the crankshaft.
Spark Plug Wires
The function of spark plugs wires is to link the coil,
distributor and spark plugs together. The coil
turns twelve volts of incoming electricity into
20,000 to 50,000 volts and sends this jolt
through the coil wire, which is connected on the
other end to the distributor. Inside the
distributor is a rotor that spins, and directs this
current to the proper spark plug wire at the
correct time, creating the "spark" at the plug.
Without these wires, no car would even turn on.
Identification
The spark plug wires normally run from the top of
the engine to the cylinders on the sides,
although some configurations differ. There will
be one plug per cylinder in normal applications,
so a V6 will have six, and a V8 will don eight
plug wires, not counting the coil wire. Each end
will have a boot on it to attach the wire either to
a spark plug, the distributor or the coil.
Generally, each end will be different sizes and
therefore impossible to mix up.
Spark plugs
Various Spark Plug Conditions
These spark plug images depict various conditions inside a
particular cylinder or all cylinders and will help troubles
Normal Condition
An engine's condition can be judged by the appearance
of the spark plugs firing end. If the firing end of a spark
plug is brown or light gray, the condition can be judged
to be good and the spark plug is functioning optimally.
hoot the problem.
Dry and Wet Fouling
Although there are many different cases, if the
insulation resistance between the center
electrode and the shell is over 10 ohms, the
engine can be started normally. If the insulation
resistance drops to 0 ohms, the firing end is
fouled by either wet or dry carbon.
Overheating
When a spark plug overheats, deposits
that have accumulated on the insulator tip
melt and give the insulator tip a glazed or
glossy appearance.
Thanks