Electronic heat relay

The utility model relates to an electronic heat relay, which relates to a device implementing overload overheating and open-phase protection to a running AC motor. An overload and overheat protection circuit is composed of a sample circuit, a half-wave rectification filter circuit, a voltage division regulation circuit, a time delay circuit, a trigger circuit and a shutdown executive circuit. An open-phase protection circuit is composed of a sample circuit, a filter circuit, a trigger circuit and a shutdown executive circuit. The electronic heat relay has the advantages of simple structure, easy fabrication, integrated functions, high safety and low cost.