Work of ELCB

Question

Specify why the ELCB do not work in case N input of the ELCB is not connected to the ground?

Answer 1

ELCB detect the earth leakage fault. Once the phase and neutral are attached in an ELCB, current will flow through the phase and that particular current will need to return neutral thus, the resultant current becomes zero. Once there, is a ground fault within the load side, current from the phase will pass through the earth and it will not return through neutral through ELCB.  Which  state that  once  side current is going and not returning and therefore, due to this difference in current, ELCB will trip and it will safe guard other circuits from the faulty loads. In case, the neutral is not grounded, fault current will definitely become high and that full fault current will come back through the ELCB, and there exist no difference in the current.