How to Use a GFCI for Grounded Appliances

GFCI Function

• When electrons leave an outlet and do not return, you're at greater risk of being electrocuted if a GFCI is not in place. A GFCI works by matching the amount of current going to an appliance against the current returning from the appliance’s electrical path. If the amount of electricity going to the appliance differs from the amount returning and there is a ground fault, the GFCI instantly causes an interruption of power by opening the circuit.

GFCI Types

• A common type of GFCI that you may find in your home are those located in power outlets that sometimes feature red and black buttons or plain white buttons that contain the words “Reset” and “Test." A GFCI on a circuit breaker helps protect circuits against overloads and ground faults, as well as the wiring connected to it. Portable GFCI come in the form of extension cords and may be used where a GFCI is not practical, such as on construction sites. Some hairstyling tools, such as blow dryers, come with their own GFCI units built into plug area.

GFCI Limitations

• If there are noise or power spikes in outside utility lines, the disruption may trip a GFCI. The same is true for some tools and appliances, which can also experience power spikes and noise. Therefore, it is not a good idea to use a GFCI on essential appliances and tools such as refrigerators, medical equipment, freezers, lights, ranges, clothes dryers, sump pumps and grounded appliances.

Grounded Appliances With GFCI

• You generally do not use a grounded appliance with a GFCI outlet because it already offers enough protection. However, the GFCI will not protect you if the grounded appliance is not grounded well. If there is an instance when you need to use a grounded appliance in a GFCI-protected outlet, do not attempt to simply use the first adapter you find. Instead, consult the appliance’s user manual or an electrician regarding the correct type of adaptor to use, because the adaptor type may differ by the type of appliance.