This photo illustrates an electrical problem which is not discernible with the naked eye. During an inspection in Aurora Colorado, my company, Magpie Property Inspections, discovered this issue with the wiring in a home. A circuit analyzer or other suitable device can be used to check circuits and wiring for a number of potential problems. In this case, having one green bar and the center red bar lighted on the device indicates that the wiring to this outlet is incorrect; the neutral and the ungrounded or “hot” conductors have been likely installed on the wrong poles in the outlet. This condition is know as “reverse polarity.” This can often happen when amateurs or non professionals attempt electrical repair or installation in a home.
In a standard outlet, the ungrounded conductor, or hot wire side enters the electrical appliance and the neutral is connected to the opposite end of the appliance’s electrical circuitry. What happens when the polarity is reversed in an outlet when an appliance is plugged in, is that the appliance circuitry is electrically charged all the time, but only functional when a switch closes the neutral wire connection and the current begins flowing.