The Siemens 3RN2013-2GW30 is a SIRIUS 3RN2 thermistor motor protection relay designed to monitor motor winding temperature via PTC thermistors. It provides safe disconnection on overtemperature, with open-circuit and short-circuit detection in the sensor circuit — critical for ATEX-rated installations where a failed sensor must not mask a fault. The relay operates on a wide supply of 24 to 240 V AC/DC (50/60 Hz) and mounts via screw or snap-on onto a 35 mm DIN rail, fitting any orientation. Rated for pollution degree 3, it handles the industrial panel environment without conformal coating concerns. The IP20 enclosure protects against finger contact but expects installation inside a cabinet. With an MTBF of 97 a and MTTFd of 303 a, the reliability data supports long service intervals — useful for MRO planners stocking spares for a multi-year run.
The supply range of 24 to 240 V AC/DC covers most control voltages in a single part — no need to order separate 24 V and 230 V variants. The relay's response time at 240 V is 0.2 ms (cited as 'at 240 V 0.2 ms'), meaning it trips fast enough to protect the motor winding before temperature rises further. Output contacts are rated 1 A at 24 V, 0.2 A at 125 V, and 0.1 A at 250 V — sufficient to signal a PLC input or drop out a contactor coil, but not for direct motor switching. The relay includes an error memory (non-volatile) and supports both auto-reset and external reset via a remote button. The initial value of 0.85 and full-scale value of 1.1 define the trip threshold relative to the cold resistance of the PTC sensor chain — standard for thermistor relays.
Width is 22.5 mm (one standard module), height 100 mm, depth 90 mm. Clearance distances: 0 mm upwards, forwards, backwards, downwards, and at the side — meaning it can be stacked tightly against other devices without derating, as long as ambient temperature stays within -25 to +60 °C. The relay accepts solid and stranded conductors from 20 to 12 AWG, so no special ferrules are required for typical panel wiring.