The ID RCCB is Residual Current devices provide the function of isolation.switching and earth leakage protection of electrical circuits. They have a residual current operated electromechanical release which operates without any auxiliary source of supply to open a circuit automatically in the case of an earth leakage fault between phase and earth greater than or equal to threshold of 10 mA,30mA,100mA,300mA or 500mA.