GFI-GFCIs

        GFIs and GFCIs are Ground fault interrupter and Ground fault
circuit interrupters. The ground fault interrupter is a receptacle that 
has the ability to open or disconnect the power from the output of the
receptacle. The ground fault circuit interrupter is a breaker that has
the ability to disconnect the power from a circuit.

        The ground fault senses a difference in the flow of current from
the hot wire through the neutral, if that difference is about 5 milliamps
or more the ground fault will trip the circuit out. It accually assumes
that if the current is not flowing in the neutral it is flowing through
something else. Some motor windings have sufficient losses to cause one
to trip out so don't use a gfi circuit for a refrigerator or washer outlet.
You should use(and the NEC requires) the use of gfi protected outlets within
6 feet of a sink, anywhere in a bathroom, in a garage or outside; anywhere
an outlet can be reached from a water source, a wet area, or earth ground,
you should use gfi protection.

        A gfi receptacle has a line side (incoming power) and a load side
(outgoing power). The receptacle will not work if the incoming power is 
connected to the load side of the receptacle. Connect the incoming power
to the line marked terminals and the continuation of the circuit (the next
outlet) to the load terminals. The one gfi will protect all the following
plugs or receptacles connected in this way. Even if you don't have a 
continuation of the circuit, connect the power to the line side of the
receptacle.

        Gfi recptacles and gfci breakers have a test button that should
cause the circuit to trip, operate the test button after installing and 
regularly there after to be sure it works properly.

      
Electricians beware:
 
	A wiggy tester will trip a gfi plug or breaker: be sure when trouble shooting
circuits where gfi or gfci might be in use that you know where to reset
circuit, or know that you wont cause problems rather than solving them, 
there is the possibility of tripping circuits that could cause the location
serious problems. Use a test meter rather than a wiggy voltage tester.
A wiggy is an excellent way to test downstream plugs in a gfi circuit to be
sure they will trip, although this method does not show the milliamperes
that the gfi is tripped out at, there is a gfi tester on the market that will
do this properly. 

        A gfci circuit breaker has 2 clearly marked terminals, one is the
hot and the other is the neutral, plus a white wire that is hanging loose,
be sure to connect the loose neutral wire to the neutral buss or terminal
strip and the hot and neutral of the circuit you are protecting to the
breaker terminals, as usual the bare ground goes to the ground strip or 
the neutral strip. After power is applied push the test button, the breaker
should trip.

        GFIs are more expensive than regular plugs or breakers but they
are a lot cheaper than someone's life and they do save lives, so use them
wherever they are needed, (anywhere electricity and water or earth are
within reach).

        It's a good idea, if you work from extension cords around homes or
or construction areas, to make up a short cord (about 3 feet) with a gfi
receptacle to plug your cords into. This way you and others are protected
from any outlet you wish to use.
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