Operation CHARM: Car repair manuals for everyone.

Basic Electricity

Electrical power flows from the power source to a load device and then back to the source of power. The electrical circuit should contain a device to open or close the circuit, such as a switch or relay, and a protective device (in case of an overload), such as a circuit breaker or a fusible link. Electrical circuits can be set up as series circuits, parallel circuits, or series/parallel circuits. The circuits in this vehicle are normally parallel circuits.

CIRCUITS

Series Circuit:




Series Circuits
In a series circuit, the electrical devices are connected to form one current path to and from the power source. In a series circuit the voltage is shared equally by all the devices in the circuit.

Parallel Circuit:




Parallel Circuits
In a parallel circuit, the electrical devices are connected to form more than one current path to and from the power source. In a parallel circuit the voltage is constant and equal for each current path.

Series/Parallel Circuit:




Series/Parallel Circuits
A series/parallel circuit consists of a single current path and a circuit with more than one current path to and from the power source.