Troubleshooting and Repairing Electrical Circuits

Electricity travels in a circle. It moves along a "hot" wire toward a light or receptacle, supplies energy to the light or appliance, then returns along the neutral wire to the source. This complete path is a circuit. In house wiring, a circuit usually indicates a group of lights or receptacles connected along such a path.

To map your electrical circuits:
Inside your electrical panel, you may discover that an electrician or previous homeowner has installed notations or lists that tell which circuit breakers or fuses control particular circuits. If your panel doesn't contain a reference like this, it's a good idea to map your circuits so, when the need arises, you can quickly find the right circuit breakers or fuses to shut them off or reset them.

Though the following instructions refer to circuit breakers, the same techniques apply to panels that utilize fuses or other types of disconnect devices.

To keep a circuit record:
If each circuit breaker isn't already numbered inside the electric panel, number them.

Make a list that you can post on the inside of the door. Numbers should correspond to each circuit breaker. After each number, note which devices the breaker controls. For an even more thorough mapping, you can sketch a floor plan and make notes on it that identify the breaker numbers for each light and receptacle throughout the house. Another helpful tip: mark the back of switch and receptacle covers with the circuit breaker's number.

To trace your home's circuits:
This is something you should do in daylight with a helper. Be aware that all of your home's power will be off at times and, when you're done, you'll have to reset clocks, timers, and the like. A helpful hint: receptacles are usually on circuits separate from lighting; major appliances such as furnaces, microwaves, washing machines, electric dryers, and electric ovens often have dedicated circuits.

1) At the electrical panel, turn off all the circuit breakers.

2) Identify any large, double (240-volt) circuit breakers first. Flip one on. Determine which major electrical appliance(s) it supplies by turning on each electric appliance (don't forget equipment such as the furnace and pool pump) until you find the ones that work.

3) Repeat with other large circuit breakers and major appliances.
4) Have a helper plug a small lamp (or electrical device) into a standard room receptacle. (If you're alone, use a radio that's turned on.)
5) Turn breakers on and off until you reach the one that turns on the lamp. Leave that breaker on and have your helper plug the lamp into other nearby receptacles; note all the ones controlled by that breaker.
6) Room lights will go on during this process. Note the circuit breaker that controls each set of lights.
7) Repeat this process with other receptacles.
8) Continue until you've located and noted all receptacle and lighting circuits.

Home electrical circuits may have a number of problems:
* Faulty wiring within the house;
* Too many lamps or appliances on one circuit;
* Defective wall switches or receptacles;
* Defective cords or plugs;
* Defective circuits within appliances.

Short circuits happen when a hot wire touches a neutral or ground wire; the extra current flowing through the circuit causes the breaker to trip or fuse to blow.