Circuits

Circuits

Electricity must have a complete or closed loop circuit to flow. A "Circuit" is defined as an unbroken, uninterrupted path which begins and ends at the same point. In the automobile that point is the battery. The electron flow must be from the battery through the wiring and consumers back to the battery. That flow represents a complete circuit.












A typical circuit will contain:
1. A battery and/or generator system (EMF or source of the electrons)
2. Conductors (wiring to deliver the electrons to the consumers)
3. Consumers (the load being placed on the system)

Any break or interruption in this circuit will cause the circuit to cease operation.

There are four basic types of circuits:
- Series
- Parallel
- Series/Parallel
- Short

Series Circuit







A Series circuit provides one path for the current flow. That path is from the source of the current (the battery) through a conductor, consumer and back to the source.

A Series circuit provides constant current flow (amps) through the entire circuit. Amps measured in any two places in the circuit will be equal.

Parallel Circuit







A Parallel circuit provides multiple current paths. In a Parallel circuit, all of the component's positive terminals are connected to one point and all of the component's negative terminals are connected to a different common point. Source voltage is the same at all loads. The current flow in a parallel circuit will be equal to the sum of the current flowing through each branch of the circuit.

Series-Parallel Circuit







A Series-Parallel circuit contains portions of the current path that are in series with each other and other portions of the path that are parallel with each other. A headlight circuit would typically be this type of Series/Parallel circuit. The headlight switch is in series with the headlights, and the headlights are in parallel branches with each other.

Short Circuit







Another type of circuit found although not by design is the "Short Circuit".
Electricity flows much like water under pressure from the point of highest pressure to the point of lowest pressure.
An unintended path of current flow, such as a grounded conductor or consumer will provide the current flow a short path to home, a "short" circuit.
Short circuits allow unlimited current flow, and with out the protection of a circuit breaker or fuse will allow overloading of the conductor and possible wire meltdown.