A control circuit for a differential switch.

摘要

A control circuit for controlling a differential switch designed to protect users by acting upon the power supply, includes a toroidal transformer effective to sense leakage currents to earth and to operate opening of the switch through a solid state switch (I1,) and a trip coil (L1). Provided between the transformer (T1) and the solid state switch (I1) is a matching capacitor (C1) that is so dimensioned as to give a maximum power transfer downstream of said transformer (T1). Also provided is a passive network (P1) the proper dimensioning of which permits operation of the switch even in presence of unidirectional and partialized loss currents.