Siemens 3RU1136-4BB0 Thermal Overload Relay 14-20A

Siemens 3RU1136-4BB0 is a Sirius thermal overload relay that provides motor protection by monitoring current in the 14–20 A range and is designed for direct mounting on Siemens size S2 contactors. It uses a 1NO+1NC output for signaling and control, supports manual and automatic reset, and mounts with screw terminals on both the main circuit and the auxiliary circuit. The relay is a size S2 device with Class 10 trip characteristics, intended for use with Siemens 3RT1033, 3RT1034, 3RT1035, and 3RT1036 contactors. Siemens lists 3RU1136-4BB0 as a phased-out product and identifies 3RU2136-4BB0 as the successor in the Sirius 3RU2 family. The 3RU1136-4BB0 datasheets and distributor listings consistently describe the unit as an overload relay designed for motor protection in these direct-mount configurations. Main circuit and auxiliary terminals are screw-terminals, enabling straightforward wiring in standard motor-control cabinets.