{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH2140-2BF40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH2140-2BF40","canonicalUrl":"https://aoctrl.com/siemens/3RH2140-2BF40","factsUrl":"https://aoctrl.com/api/mcp/products/3RH2140-2BF40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RH2140-2BF40 auxiliary contactor, size S00, 4 NO instantaneous contacts, 110 V DC coil, screw and snap-on 35 mm DIN rail mounting.","salesMarkdown":"## 4 NO auxiliary switching in a size S00 frame The 3RH2140-2BF40 is a SIRIUS auxiliary contactor with four normally-open instantaneous contacts, sized in the S00 frame. It is designed for signal-level switching in control circuits, not motor power — the 4 NO configuration gives you four independent signal paths that close when the coil is energized. Closing power is 4 W, holding power also 4 W, meaning the coil driver must deliver a continuous 4 W load without thermal derating. Switching capacity varies sharply with DC voltage: at 24 V it handles 10 A, at 110 V it drops to 3 A, and at 600 V it is rated only 0.26 A. For AC loads at 230 V it switches 10 A, at 400 V it switches 3 A. This voltage-dependent derating is the primary selection constraint — the same contact pair cannot carry its full 24 V rating at a higher DC bus voltage. ## DIN rail fit and panel clearances This means it fits in tight sub-panels where the rail is not perfectly vertical. Physical envelope is 70 mm high, 45 mm wide, 73 mm deep. At 45 mm wide, four units fit in a standard 180 mm DIN-rail segment — plan your gland-plate layout accordingly. Pollution degree 3 means it is rated for conductive pollution environments typical of industrial control panels — no conformal coating required for normal factory-floor atmospheres. ## Lifecycle, compliance, and sourcing posture Mechanical life is rated 30,000,000 operating cycles typical — this is the wear-out limit for the contact mechanism, not the electrical endurance under load. At the maximum AC switching rate of 10,000 operations per hour, the mechanical life translates to roughly 3,000 hours of continuous cycling, or about 125 days of 24/7 operation.","metaTitle":"Siemens 3RH2140-2BF40 SIRIUS Auxiliary Contactor, 4 NO, S00","metaDescription":"Siemens 3RH2140-2BF40 SIRIUS auxiliary contactor, size S00, 4 NO contacts, 110 V DC coil. Screw and snap-on 35 mm DIN rail. Active production, sourced per RFQ.","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 ... 13 ms","title":"3RH2140-2BF40","Height":"70 mm","Upwards":"10 mm","Forwards":"10 mm","Downwards":"10 mm","Arcing Time":"10 ... 15 ms","At The Side":"6 mm","Rated Value":"110 V","description":"Contactor relay, 4 NO, 110 V DC, Size S00, Spring-type terminal","Initial Value":"0.8","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":"1.1","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":"Auxiliary contactor","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","Product Extension Auxiliary Switch":"Yes","closing power of magnet coil at DC":"4 W","holding power of magnet coil at DC":"4 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","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","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","Of The Contactor With Added Electronically Optimized Auxiliary Switch Block Typical":"5 000 000","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,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/78d591f06f882e7c09e5122fd5dc6e4e.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=71572&mlfb=3RH2140-2BF40"},"ai":{"faq":[{"question":"What is the switching capacity of this contactor at different DC voltages?","answer":"The voltage-dependent derating is the primary selection constraint — always check the specific DC voltage in your control circuit."},{"question":"What compliance documentation does Siemens provide for 3RH2140-2BF40?","answer":"RoHS compliance is confirmed with a substance prohibition date of 2009-01-10. The part carries pollution degree 3 rating for industrial environments. Standard Siemens documentation includes the declaration of conformity and CE marking — these are available through the Siemens Industry Online Support portal."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH2140-2BF40","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/3RH2140-2BF40 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}