{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH2140-2KB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH2140-2KB40","canonicalUrl":"https://aoctrl.com/siemens/3RH2140-2KB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RH2140-2KB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS coupling relay, size S00, 4 NO instantaneous contacts, 24 VDC coil, screw and snap-on mounting on 35 mm DIN rail, 73 mm depth, 45 mm width.","salesMarkdown":"The Siemens 3RH2140-2KB40 is a SIRIUS coupling relay — size S00 frame — built to switch auxiliary circuits in control panels. It carries 4 normally-open instantaneous contacts, rated 10 A at 24 V and 10 A at 230 V, with a 24 VDC coil drawing 2.8 W closing power. The built-in suppressor diode handles the coil's inductive kick, so you don't need to add one externally. The S00 footprint — 45 mm wide, 70 mm tall, 73 mm deep — fits tightly in a crowded enclosure. ## Switching capability by voltage Rated operational current varies by voltage and load type: 10 A at 24 V AC/DC, 4.7 A at 60 V, 3 A at 110 V, 1.2 A at 220 V, 10 A at 230 V, 3 A at 400 V, 0.5 A at 440 V, 2 A at 500 V, 0.26 A at 600 V, and 1 A at 690 V. Mechanical endurance is 30 million operations; electrical switching frequency is 10,000 cycles per hour at AC, with arcing time 10–15 ms. That's a lot of cycles for a relay this size — good for high-duty auxiliary circuits like signal lamps or PLC inputs.","metaTitle":"Siemens 3RH2140-2KB40 SIRIUS Coupling Relay, 4 NO, 24 VDC, 1","metaDescription":"Siemens 3RH2140-2KB40 SIRIUS coupling relay, size S00, 4 NO contacts, 24 VDC coil, 10 A rated current. Screw/snap-on 35 mm DIN rail. Current production. Available to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"73 mm","Width":"45 mm","at AC":"10 000 1/h","at DC":"7 ... 20 ms","Height":"70 mm","Upwards":"10 mm","Forwards":"10 mm","Downwards":"10 mm","Arcing Time":"10 ... 15 ms","At The Side":"6 mm","Rated Value":"24 V","Initial Value":"0.7","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting onto 35 mm standard mounting rail","Full-Scale Value":"1.25","Mounting Position":"+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface","Size Of Contactor":"S00","Solid Or Stranded":"2x (0,5 ... 4 mm²)","Product Brand Name":"SIRIUS","Degree Of Pollution":"3","Product Designation":"Coupling relay for switching auxiliary circuits","at 24 V rated value":"10 A","at 60 V rated value":"4.7 A","Of Contactor Typical":"30 000 000","at 110 V rated value":"3 A","at 220 V rated value":"1.2 A","at 230 V rated value":"10 A","at 400 V rated value":"3 A","at 440 V rated value":"0.5 A","at 500 V rated value":"2 A","at 600 V rated value":"0.26 A","at 690 V rated value":"1 A","Instantaneous Contact":"4","Relative Humidity Minimum":"10 %","Substance Prohibitance (Date)":"10/01/2009","Design Of The Surge Suppressor":"suppressor diode","Product Extension Auxiliary Switch":"No","closing power of magnet coil at DC":"2.8 W","holding power of magnet coil at DC":"2.8 W","Surge Voltage Resistance Rated Value":"6 kV","at AWG cables for auxiliary contacts":"2x (20 ... 12)","operating frequency at DC-12 maximum":"1 000 1/h","operating frequency at DC-13 maximum":"1 000 1/h","operational current at AC-12 maximum":"10 A","reference code according to IEC 81346-2":"K","Finely Stranded With Core End Processing":"2x (0.5 ... 2.5 mm²)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","with low demand rate according to SN 31920":"40 %","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","with high demand rate according to SN 31920":"73 %","number of NO contacts for auxiliary contacts":"4","Type Of Voltage Of The Control Supply Voltage":"DC","contact rating of auxiliary contacts according to UL":"A600 / Q600","Identification Number And Letter For Switching Elements":"40 E","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Type Of Electrical Connection For Auxiliary And Control Circuit":"spring-loaded terminals","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Design Of The Fuse Link For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 10 A","design of the miniature circuit breaker for short-circuit protection of the auxiliary circuit up to 230 V":"C characteristic: 6 A; 0.4 kA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/601bb9e78838b91688e278ea5987680b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=534969&mlfb=3RH2140-2KB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH2140-2KB40/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RH2140-2KB40 and get a price?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"What is the closest functional second-source to 3RH2140-2KB40?","answer":"The 3RH2140-1BP40 is a close peer — same S00 frame, 4 NO contacts, 24 VDC coil, but without the built-in suppressor diode. If your panel relies on the internal diode, the -2KB40 is the direct fit; otherwise the -1BP40 drops into the same DIN footprint without rewiring."},{"question":"Will 3RH2140-2KB40 drop into a panel specified for 3RH2140-1BP40?","answer":"Yes — same S00 frame, same 45 mm width, same screw/snap-on DIN rail mount. The only difference is the built-in suppressor diode on the -2KB40, so no wiring change needed."},{"question":"What compliance documentation does Siemens provide for 3RH2140-2KB40?","answer":"RoHS compliance per the 10/01/2009 substance prohibition date. The part carries pollution degree 3 rating for industrial environments."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH2140-2KB40","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/3RH2140-2KB40 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}}