GM – CAMARO 1982-1992 – Repair Guide (Checked by WxMax) 128
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Size - the larger the wire size being used, the less resistance the wire will
have. This is why components which use large amounts of electricity
usually have large wires suppl ying current to them.
• Length - for a given thickness of wire, the longer the wire, the greater the
resistance. The shorter the wire, the less the resistance. When
determining the proper wire for a circ uit, both size and length must be
considered to design a circuit that can handle the current needs of the
component.
• Temperature - with many materials, the higher the temperature, the
greater the resistance (positive temper ature coefficient). Some materials
exhibit the opposite trait of lower re sistance with higher temperatures
(negative temperature coefficient). Thes e principles are used in many of
the sensors on the engine.
OHM'S LAW
There is a direct relationship between current, voltage and resistance. The
relationship between current, voltage and resistance can be summed up by a
statement known as Ohm's law.
Voltage (E) is equal to amper age (I) times resistance (R): E=I x ROther forms of
the formula are R=E/I and I=E/R
In each of these formulas, E is the voltage in volts, I is the current in amps and
R is the resistance in ohms. The basic point to remember is that as the
resistance of a circuit goes up, the amount of current that flows in the circuit will
go down, if voltage remains the same.
The amount of work that the electricity can perform is expressed as power. The
unit of power is the watt (w). The re lationship between power, voltage and
current is expressed as:
Power (w) is equal to amperage (I) times voltage (E): W=I x EThis is only true
for direct current (DC) circuits; The alte rnating current formula is a tad different,
but since the electrical circuits in mo st vehicles are DC type, we need not get
into AC circuit theory.
ELECTRICAL COMPONENTS
POWER SOURCE
Power is supplied to the vehicle by tw o devices: The battery and the alternator.
The battery supplies electrical power dur ing starting or during periods when the
current demand of the vehicle's electrical system exceeds the output capacity of
the alternator. The alternator supplies electrical current when the engine is
running. Just not does the al ternator supply the current needs of the vehicle, but
it recharges the battery.
