GFCI & AFCI
What is a Ground Fault Circuit Interrupter (GFCI)?
A Ground Fault Circuit Interrupter (GFCI) works by detecting any loss of electrical current in a circuit. When a loss is detected, the GFCI turns the electricity off before severe injuries or electrocution can occur. A painful shock may occur during the time that it takes for the GFCI to cut off the electricity so it is important to use the GFCI as an extra protective measure rather than a replacement for safe work practices.
GFCI wall outlets can be installed in place of standard outlets to protect against electrocution for just that outlet, or a series of outlets in the same branch. A GFCI Circuit Breaker can be installed on some circuit breaker electrical panels to protect an entire branch circuit. Plug-in GFCIs can be plugged into wall outlets where appliances will be used.
Test the GFCI monthly. First plug a "night light" or lamp into the GFCI-protected wall outlet (the light should be turned on), then press the "TEST" button on the GFCI. If the GFCI is working properly, the light should go out. If not, have the GFCI repaired or replaced. Reset the GFCI to restore power.
If the "RESET" button pops out but the light does not go out, the GFCI has been improperly wired and does not offer shock protection at that wall outlet. Contact a qualified electrician to correct any wiring errors.
Arc Fault Circtuit Interrupter (AFCI) Breakers
Arc-Fault Circuit Interrupter Breakers Arc-Fault Circuit Interrupter Breakers, or AFCIs are now required in new construction by the Electrical Safety Authority (ESA). What are they? Do you need them?
The AFCI breaker performs a different job entirely from GFIs, Ground Fault Interrupter (GFCI) breakers and outlets. A GFI protects you from becoming part of the circtuit and getting a shock. The AFCI breaker protects you and your house from a fire.
How? Well, when a Hot wire makes a solid contact with a ground or a neutral, the current draw will be high enough to trip the breaker. But if the contact is intermittent and not a solid contact due to loose or corroded connections or failing insulation, what develops is an arc. The arc causes heat, which left uncorrected could eventually wind up causing a fire. The AFCI breaker detects an arc by the characteristic wave an arc causes in the electrical flow. When it sees an arc fault of large enough magnitude, it will trip the breaker.
They are expensive ($45 to $55 and up vs. $10 for a conventional breaker). Presently the code only requires them in circuits serving bedrooms. That doesn't mean other circuits can't benefit from their protection, but that is all that is required at this time.
But what are the hazards they are protecting you from? Well, problems in home wiring, like arcing and sparking, are associated with more than 40,000 home fires each year. These fires claim over 350 lives and injure 1,400 victims annually. These are the very fires the AFCI breaker is intended to prevent.
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