an home residential electrical panel with the panel door open and the circuit breakers exposed

Electric Circuit

Originally contributed by Jeff Butler • last updated 2/18/2021

Not every home repair project is going to require you to access your home’s electrical system and know all about circuits. But having a firm grasp on the fundamentals of electric circuits could come in handy for more serious renovations.


When it comes to powering your home, the term electric circuit typically refers to the circular journey that electricity takes from your home’s main electrical panel to a group of fixtures or appliances and then back again. In general, an electric circuit consists of: a power source that acts as the supply and return of an electric current; conductors, typically in the form of copper wires, that carry the current through the circuit; and a load that consumes the electric current (i.e. a device, such as a television or microwave). Most modern homes are equipped with circuit breakers, which are designed to trip or blow if the current in an electric circuit suddenly becomes too high.

What Is A Short Circuit?

When electricians use the term short circuit, they are often referring to a problem in an electrical circuit that allows excessive power to flow back to the power source (aka the return). When this happens, typically the circuit breaker or fuse will blow or trip to prevent damage and fires:

  • Short circuits around the home typically happen when an electronic device, such as a radio or a fan, with faulty wiring is suddenly plugged in to an outlet, causing a circuit breaker or fuse to trip or blow.
  • In some cases, damage to a home’s electrical system could be the cause of a short circuit. Specifically, damage to wires and cables from nails and screws or pets and rodents can sometimes allow unintended connections to occur along the circuit.