{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RN2012-1BW31","brand":"Siemens","brandSlug":"siemens","productSlug":"3RN2012-1BW31","canonicalUrl":"https://aoctrl.com/siemens/3RN2012-1BW31","factsUrl":"https://aoctrl.com/api/mcp/products/3RN2012-1BW31","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RN2 thermistor motor protection relay, 3RN2012-1BW31, rated supply 24... 240 V AC/DC, output 1 A at 24 V, IP20, 22.5 mm wide.","salesMarkdown":"The Siemens 3RN2012-1BW31 is a SIRIUS 3RN2 thermistor motor protection relay. It monitors motor winding temperature via PTC thermistors, tripping the output when the motor overheats. Rated supply 24... 240 V AC/DC, 50/60 Hz. Output rated 1 A at 24 V, 0.2 A at 125 V, 0.1 A at 250 V. IP20 enclosure, 22.5 mm wide, 100 mm high, 90 mm deep. Any mounting position. Current production stage. Rated supply 24... 240 V AC/DC covers 24 V and 240 V systems. Output rated 1 A at 24 V drops to 0.2 A at 125 V and 0.1 A at 250 V — enough to drive a contactor coil or PLC input, but not a direct motor starter. Bistable evaluation unit with open-circuit and short-circuit detection in the sensor circuit. No triggering on control supply failure. Auto-reset and external reset available. Error memory stores the last fault. Operates -25... +60 °C, stores -40... +85 °C. Pollution degree 3, so it handles conductive dust and condensation environments. Any mounting position. Screw terminals accept 1x 20-12 AWG solid or stranded, 2x 20-14 AWG solid for daisy-chaining. Strip length 8 mm. Spring-cage not used here. LED display version gives visual status. Galvanic isolation between input and output, and between outputs.","metaTitle":"Siemens 3RN2012-1BW31 SIRIUS Thermistor Motor Protection Rel","metaDescription":"Siemens SIRIUS 3RN2012-1BW31 thermistor motor protection relay, 24-240 VAC/DC rated supply, 1 A at 24 V output, IP20, current production. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Process / Temperature Controllers"],"specifications":{"Depth":"90 mm","Solid":"20 ... 12","Width":"22.5 mm","Height":"100 mm","Upwards":"0 mm","at 24 V":"1 A","Forwards":"0 mm","Stranded":"20 ... 12","at 125 V":"0.2 A","at 240 V":"0.2 ms","at 250 V":"0.1 A","Backwards":"0 mm","Downwards":"0 mm","auto-RESET":"Yes","At The Side":"0 mm","Rated Value":"24 ... 240 V","Error Memory":"Yes","Initial Value":"0.85","During Storage":"-40 ... +85 °C","External Reset":"Yes","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-40 ... +85 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail","Full-Scale Value":"1.1","Product Category":"SIRIUS 3RN2 thermistor motor protection","Product Function":"thermistor motor protection","Mounting Position":"any","Product Brand Name":"SIRIUS","Between The Outputs":"Yes","Degree Of Pollution":"3","Product Designation":"Thermistor motor protection relay","at AWG cables solid":"1x (20 ... 12), 2x (20 ... 14)","display version LED":"Yes","protection class IP":"IP20","at 50 Hz rated value":"24 ... 240 V","at 60 Hz rated value":"24 ... 240 V","Design Of The Product":"Bistable evaluation unit, open-circuit and short-circuit detection in the sensor circuit (no triggering in the event of control supply voltage failure)","Between Input And Output":"Yes","Relative Metering Precision":"2 %","Substance Prohibitance (Date)":"05/28/2009","Type Of Electrical Connection":"screw-type terminals","Dynamic Open-Circuit Detection":"Yes","Material Of Switching Contacts":"AgSnO2","Operating Frequency Rated Value":"50 ... 60 Hz","For Auxiliary And Control Circuit":"screw-type terminals","Design Of The Electrical Isolation":"galvanic isolation","Relative Humidity During Operation":"70 %","Surge Voltage Resistance Rated Value":"4 kV","due to burst according to IEC 61000-4-4":"2 kV (power ports) / 1 kV (signal ports)","reference code according to IEC 81346-2":"K","Finely Stranded With Core End Processing":"0.5 ... 4 mm²","Tightening Torque With Screw-Type Terminals":"0.6 ... 0.8 N·m","number of CO contacts for auxiliary contacts":"2","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"0","shock resistance according to IEC 60068-2-27":"11g / 15 ms","Between The Voltage Supply And Other Circuits":"Yes","Type Of Voltage Of The Control Supply Voltage":"AC/DC","vibration resistance according to IEC 60068-2-6":"10 ... 55 Hz: 0.35 mm","Mechanical Service Life (Operating Cycles) Typical":"10 000 000","electrostatic discharge according to IEC 61000-4-2":"6 kV contact discharge / 8 kV air discharge","Buffering Time In The Event Of Power Failure Minimum":"40 ms","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Thermal Current Of The Switching Element With Contacts Maximum":"5 A","continuous current of the DIAZED fuse link of the output relay":"6 A","Product Component Removable Terminal For Auxiliary And Control Circuit":"Yes"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/3RN2012-1BW31/alternatives.json"},"ai":{"faq":[{"question":"Does it fit a standard 35 mm DIN rail?","answer":"Yes, screw and snap-on mounting onto 35 mm DIN rail. 22.5 mm wide, any mounting position."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RN2012-1BW31","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3RN2012-1BW31 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}