The ground fault sensor in a Qwik-Gard GFCI continuously monitors the current flow in the load and neutral conductors. The sensor compares the current flow in all directions. If the current flowing back to the source is less than the current flowing out to the load, a ground fault exists. When the difference in current flow exceeds 6 mA, the sensor sends a signal to trip the GFCI. The trip will be indicated by the Visi-Trip indicator and the operating handle will move to the center tripped position.