What is a GFCI?
They are often electrical outlets with the colored “Test” and “Reset” buttons. GFCI is an acronym for Ground Fault Circuit Interrupter and have been used in homes since the 1970’s
Why Are They Important?
GFCI’s are designed to shut power off if there is a very small leak of electricity (a ground fault). Generally speaking, normal outlets are shut off by a fuse or breaker if more than 15 amps flows. This prevents fires, but since people can be killed by 1 amp or less, fuses may not protect people from shock.
How Do They Work?
A GFCI detects a leak by comparing how much electricity comes back through the white wire to how much was sent in the black wire. When everything is working correctly, the current flow is the same. If a little electricity is leaking out, it may be going through a ground wire or through part of the house. If this happens, the black wire will have more electricity than the white wire. Electricity, like most people, will follow the path of least resistance. If a person touches a leaky electrical system, they may present a better route to ground for electricity, since they may offer very little resistance.
Where Are They Used?
In Canada, GFCI’s are now required by Code for numerous applications such as outdoor outlets, bathroom outlets and whirlpool outlets. Electrical systems for swimming pools are also GFCI protected.
Can They Be Added To Older Houses?
Yes, GFCI’s can be added to any electrical system. They are more expensive than regular outlets but should be more commonly viewed as inexpensive insurance. While they do not replace grounding systems exactly, some Codes do allow GFCI’s in lieu of grounding in some cases.