Siemens 3RU1126-1CB0 Overload Relay

Siemens 3RU1126-1CB0 is a Sirius thermal overload relay that provides motor protection when mounting on a compatible Siemens contactor. This 3-pole device protects three-phase motors with a main current rating of 1.8–2.5 A, and it carries Siemens Class 10 thermal protection in Size S0, with a 1NO+1NC auxiliary contact for signaling. Rated for up to 690 V AC, it features front IP20 protection and is built for operating environments from -20 °C to +70 °C (ambient), up to 2,000 m altitude, with 8 g/10 ms shock resistance. Typical active power loss is 6 W (total) at rated current, making it suitable for integration into motor protection circuits that require minimal standby loss. Designed for use with three-phase motors, this overload relay pairs with Siemens 3RT/SIRIUS contactors to provide reliable overload protection within the 1.8–2.5 A range and to offer a local status signal via its auxiliary contact.