The Siemens 3RN1013-2BW01 is a thermistor motor protection evaluation unit from the SIRIUS 3RN1 series. It monitors motor winding temperature via PTC thermistors and trips on over-temperature, with a built-in reclosing lockout that prevents automatic restart after a fault — a feature that saves a service call when the motor needs a manual reset before re-energizing. Supply voltage covers 24-240 V AC/DC, so it works across control voltages from 24 VDC PLC outputs to 230 VAC panel supplies without a separate transformer. Rated for -25 to +60 °C ambient, which covers most cabinet interiors short of direct heat-source adjacency. The LED display gives a quick visual on trip status without needing a multimeter.
The 91 mm depth and 103 mm height leave clearance for standard enclosure depths — no panel-depth surprises. Two CO (changeover) auxiliary contacts handle the trip signal and status feedback; no dedicated NC or NO contacts are present, so the CO contacts are what you wire for both alarm and reset. Spring-loaded terminals accept 0.2-2.5 mm² conductors. Strip length around 8-10 mm for a clean seat under the cage.