The Siemens SIRIUS 3RN2000-1AW30 is a thermistor motor protection relay from the 3RN2 family, designed as a compact evaluation unit for bimetallic switches. It accepts a supply voltage of 24 to 240 V AC/DC (50/60 Hz) and provides a single-pole output rated at 1 A at 24 V, 0.2 A at 125 V, and 0.1 A at 250 V. The relay features automatic reset (no external reset), an LED status display, and IP20 finger-safe protection. The unit occupies 17.5 mm width, 100 mm height, and 90 mm depth. Clearance to adjacent devices is 0 mm in all directions (upwards, downwards, forwards, backwards, sideways).
The 3RN2000-1AW30 is listed as current production, so it remains available through standard Siemens distribution channels. This is not a phase-out or NRND part. Sourcing is straightforward — specify the order code against an RFQ for your BOM line. The part carries a RoHS compliance date of 05/28/2009, indicating it meets the EU RoHS directive for substances of concern. Pollution degree 3 (industrial environment) is rated, and the operating temperature range is -25 to +60 °C, with storage/transport from -40 to +85 °C.
Wiring and connection notes
The terminal block accepts solid or stranded wire from 20 to 12 AWG (1x 20-12, 2x 20-14 for solid). The design includes a jumper between terminal A1 and the root of the changeover contact, so verify the circuit topology before commissioning — this is not a standard isolated contact arrangement. The relay evaluates the resistance of a bimetallic PTC thermistor sensor; the trigger threshold is set at an initial value of 0.85 and a full-scale value of 1.1 (relative metering precision 9%). Galvanic isolation exists between input and output.
Verification at incoming inspection
For quality and counterfeit detection, check the nameplate for the SIRIUS brand marking and the 3RN2000-1AW30 order code. The IP20 housing (17.5 mm wide) is a standard SIRIUS compact form factor. The LED window should be present. The screw and snap-on DIN rail latch is integral. No external reset button is fitted — auto-reset only. The date code and lot traceability are on the side label; match to the packing slip and Siemens factory documentation. Any deviation in dimensions (90 mm depth, 100 mm height) or wire range (20-12 AWG) is a red flag.