The best way to describe this device is to say it has a circuit board inside it which is constantly measuring the flow of electrons within the circuit. When one side of the circuit gets out of balance from the other the circuit board detects a fault and trips shutting off the flow of electricity. Think of it as a river flowing underground which resurfaces a short distance away. If the river has always had the same flow and all of a sudden only half the volume emerges from the ground you would know there was a problem. The GFI works the same way. If even a little of the current strays into your body for instance, the GFI will detect it and trip potentially saving your life. We know that as little as 1 amp of electrical current can kill a person. The breaker in most cases will not trip until it reaches a load of 15 Amps. The GFI will trip at 5 milliamps or 5% of one amp.
: I am told there is a new invention called a GFCI that makes electrical plugins safer in areas near water. Can you explain how these work and why they are safer?
Mar 2, 2014