Most household electrical wiring, such as receptacle outlets and lighting wiring, typically uses parallel circuits. Parallel circuits are often used in household electrical wiring so that the lights continue to work even when the television is turned off.
A parallel circuit is composed of two or more independent paths that are linked to the source. The full circuit voltage flows through every load in the circuit. For example, if a parallel circuit has two 60-watt light bulbs and a full circuit voltage of 120 volts, each of the bulbs gets 120 volts from the source. When another 60-watt bulb is connected to the circuit, it also receives the same number of volts and produces the same brightness level as the other two bulbs.
The current flows through the closed paths instead of the open paths. When an item in the circuit fails to work, current doesn’t travel through the broken path, but it still flows through the other paths of the circuit.
A possible disadvantage of using a parallel circuit is that the amperage from the source rises whenever an extra load is linked to the circuit. This means that it’s possible to add more loads and eventually overload a circuit, as more current is needed to make the items work.