The Siemens 3RN1012-2BG00 is a thermistor motor protection standard evaluation unit designed to monitor motor winding temperature via PTC thermistors. It operates on 110 V AC at both 50 Hz and 60 Hz, making it a straight swap for panels wired to either line frequency. The unit provides 2 changeover (CO) contacts for auxiliary signaling or trip output, with no normally-open or normally-closed auxiliary contacts — all switching is through the CO pair.
Mounting & Connections
Housing is 22.5 mm wide, 103 mm tall, and 91 mm deep — a standard single-module footprint that clips onto a DIN rail with the screw-and-snap-on fastening method. Spring-loaded terminals on the auxiliary and control circuit accept solid or ferruled stranded wire without needing a screwdriver torque check. IP20 rated, so it belongs in a clean enclosure, not a wet panel. Ambient operating range is -25 to +60 °C, which covers most indoor industrial environments.
Compliance & Documentation
The unit carries a substance prohibitance date of May 28, 2009, aligning with RoHS and REACH compliance expectations for that era. The reference code per IEC 81346-2 is K, which maps to relay/contactor functions in system documentation. No UL or CSA marks are listed in the spec record, so verify with your local authority if the installation requires third-party certification.