Inspect The Area
Okay, let’s say your circuit is feeding a kitchen countertop outlet. You go to the kitchen and inspect to see if there is anything obvious that may have caused an overload, a ground fault, or a short. Confused? Let me explain.
An overloaded circuit simply means that there is more power being used than is available via the breaker or fuse. A 20 amp breaker only allows up to 20 amps to flow through it before it trips. Likewise, a 20 amp fuse will only allow 20 amps to flow through it before it blows. It has been my experience that a fuse will generally blow easier than a breaker will trip when the maximum is reached. However, a fuse can only blow once while a breaker can be reset.
A ground fault occurs when the flow of current is not balanced between the hot wire and neutral wire. A specially designed outlet called a GFI (ground fault interrupter) is used that detects this and disconnects a circuit. A GFI is used where water is within five feet of the outlet. This outlet has a test button and a reset button built into it.
Instead of a GFI outlet, you may have a GFI breaker. When there is a problem, say a mixer falls into your sink water, the GFI opens the circuit and cuts off electricity to the mixer. Likewise, it will trip if you have a hand in the water while touching an appliance that may have a frayed wire. The built-in safety feature could save you or your family’s life.
A short is caused when the hot wire and either the neutral or ground wire make contact. In a typical panel, the black wire is the hot wire, the white wire is the neutral and the green or bare copper wire is the ground. Shorting of a circuit could be caused by someone driving a nail or screw into a wall and through the wire supplying the outlet.
Some people have problems with an occasional mouse in the house. These critters love to chew on everything and sometimes they chew right through the wire’s insulation and short out a circuit. An appliance, say a vacuum, may have a motor lock up and its motor windings may short together causing the problem.