The utility model relates to a switch remote signalling changer. The N switching value acquisition circuit that is connected including microcontroller circuit and with this microcontroller circuit, one be used for the communication circuit that communicates by letter with the host computer, include still that one is used for being the power supply circuit that whole changer was supplied power, switching value acquisition circuit including the capacitor step -down circuit who is used for detecting commercial power break -make state, the direct current DCDC circuit that is used for detecting thedry contact switch and with capacitor step -down circuit, direct current DCDC circuit connection's optoelectronic coupler, optoelectronic coupler still is connected to microcontroller circuit. The utility model discloses can support nearly 20 tunnel interchange AC220V's switch remote signalling monitoring, support to adopt monitoring of active AC220V direct access or dry contact to insert, need not multiple conversion module, simple to operate is simple, and adopts RS485 communication mode, supports remote maintenance.