The Siemens 3RN2010-2BW30 is a SIRIUS 3RN2 thermistor motor protection relay — a standard evaluation unit designed for bimetallic PTC sensors. It monitors motor winding temperature and trips the output when the sensor resistance exceeds the threshold, which is the core function of this class: protecting motors from overheating without nuisance trips on inrush. Supply range is 24 to 240 VAC/DC, so it works across common control voltages without needing a separate power supply module. The output relay switches 1 A at 24 V, enough to drive a contactor coil or PLC input directly. That width is standard for a single-function protection relay — it fits in a crowded panel without eating up rail space.
Siemens 3RN2010-2BW30 SIRIUS thermistor motor protection rel
MPN3RN2010-2BW30
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Siemens SIRIUS 3RN2 thermistor motor protection relay, 3RN2010-2BW30, 24-240 VAC/DC supply, 1 A at 24 V output, IP20, 22.5 mm width.
Sourced new & surplus through independent channelsAuthenticity-screened · ESD-safe packingListing updated Jul 2026
Specifications
| Parameter | Value |
|---|---|
| Product function | thermistor motor protection |
| Product designation | Thermistor motor protection relay |
| Product line / brand name | SIRIUS |
| Parameter | Value |
|---|---|
| Rated value (50 Hz) | 24 ... 240 V |
| Rated value (60 Hz) | 24 ... 240 V |
| Parameter | Value |
|---|---|
| Electrical connection type | spring-loaded terminal (push-in) |
| Parameter | Value |
|---|---|
| Ingress protection (IP rating), wired | IP20 |
| Installation altitude, max. | 2 000 m |
| Parameter | Value |
|---|---|
| Fastening method | screw and snap-on mounting onto 35 mm DIN rail |
| Mounting position | any |
| Width | 22.5 mm |
| Height | 100 mm |
| Depth | 90 mm |
| Conductor cross-section, solid | 20 ... 12 |
| Conductor cross-section, finely stranded (with ferrule) | 0.5 ... 2.5 mm² |
| Mounting clearance, top | 0 mm |
| Mounting clearance, rear | 0 mm |
| Mounting clearance, side | 0 mm |
| Mounting clearance, front | 0 mm |
Product details
Frequently asked questions
What are the key ratings for this relay?
Supply voltage: 24 to 240 VAC/DC. Output: 1 A at 24 V, 0.2 A at 125 V, 0.2 A at 240 V. Housing: 22.5 mm wide, IP20, mounts on 35 mm DIN rail. Operating temperature: -25 to +60 °C.
What is the mounting method?
Screw and snap-on mounting onto 35 mm DIN rail. Mounting position is any orientation.
Does it have an auto-reset function?
Yes, auto-reset is available. There is no external reset input and no error memory.
MPN
3RN2010-2BW30