Siemens SIRIUS 3RU2 Thermal Overload Relays provide inverse-time delayed protection up to 100A for loads with normal starting against impermissibly high temperature rises due to overload or phase failure. The Siemens SIRIUS 3RU2 Thermal Overload Relays protect three-phase and single-phase AC and DC motors. The series is suitable for any industry needing optimum inverse-time delayed protection of electrical loads under normal starting conditions (CLASS 10, 10A). The relays compensate for temperatures over a -40°C to +60°C range according to IEC 60947-4-1. From +60°C to +70°C, the upper set value of the setting range must be reduced by a specific factor.
