JRS2 (3UA) series thermal relay (bimetallic thermal overload relay)is suitable for AC 50 / 60Hz, voltage to 660-1000v, current to 630A long-term work or intermittent long-term work. thermal relay is generally used as motor thermal overload protection, with open phase protection, temperature compensation, trip indication function, automatic and manual reset, and can be connected with contactor. It can also be installed independently.