So far, so good. . .anyone have any input from outside North America?
Here in Argentina they are mandatory for new residential buildings.
We don´t use GFI's integrated into an outlet but "general" GFI's integrated into the main circuit breaker panel.
The ussual configuration (the one that gives minimum cost and still passes the code) is one GFI as a main switch and several thermo-magnetic breakers (one for each circuit). Of course, when the GFI trips this gives you a "total blackout"
- But a GFI costs much more than a circuit breaker.
It not only protects people against fatal shocks, it also protects appliances, wiring and the entire building against
fire. When there is an overload and the wiring starts to melt or burn, if there is a ground wire along the power wiring there will be a ground leak and the GFI will trip.
I have seen many cases when a faulty appliance was "saved" by the GFI. For instance, a dishwasher with a stuck float switch that flooded itself and tripped the GFI. After drying it down and repairing the float switch it was OK, but if the flooded circuits had continued to operate until they tripped a 25A circuit breaker we would have a mess to clean up and repair.
I have installed GFI's in existing homes (at home and at some friend's), and it's a pain in the ...... In an old system, if there is a small leak somewere (and Murphy says of course there will be one
), it will trip and keep tripping until you find ans repair the leak.
The most
confusing
case was at my parent's (a brand new building). We had the GFI tripping at random times, for no apparent reason
. We eventually tracked it to the fridge: Sometimes when the fridge started the GFI tripped. We then pluged the fridge into a non-GFI outlet we had, and found that, sometimes, the GFI tripped when the fridge started
After some time we found that a fan's motor had a
ground leak inside its windings, but it was almost at the
neutral side, so it worked OK without tripping the GFI. But when the fridge started there was a voltage drop in the neutral wire, and the leak between neutral and ground was enough to trip the GFI (even when the fan was off, and with the fridge in a non-GFI otlet) We replaced the fan and we had no more false GFI tripping for years
.