GFCI "(Ground Fault Circuit Interrupter) is a ground fault leakage protector. It is a safety device that the U.S. government enforces to protect people's personal safety. GFCI aims to protect people from severe or fatal electric shocks.
Because the GFCI detects ground faults, it can also prevent some electrical fires and reduce the severity of other interrupted currents. The working principle is as follows: In the wiring system in the home, in a power outlet, under normal conditions, the currents of the hot line and the neutral line should be equal, and the GFCI monitors the current difference, but if the difference is greater than 10 mA ( Milli Amps), it can cut off the power in 25 milliseconds, thus ensuring personal safety. The GFCI interrupts power faster than blinking to prevent deadly power. You will only feel acupuncture pain, will not be electrocuted, or receive a serious blow.