Receptacle testers are used to test wiring in electrical receptacles. They identify outlets that are open ground, open hot or open neutral; hot, hot on neutral, or ground reversed with open hot; and which have faulty wiring or reverse polarity. Receptacle testers can also be used to identify live circuits, determine the ground leg of a two-wire receptacle, and to check three-wire grounding outlets.
Ground Fault Circuit Interrupter (GFCI) testers check for the integrity of GFCI devices.
