{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1140-2BM40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1140-2BM40","canonicalUrl":"https://aoctrl.com/siemens/3RH1140-2BM40","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1140-2BM40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS auxiliary contactor, size S00, 4 NO instantaneous contacts, 220 VDC coil, screw and snap-on mounting, IP20 front protection.","salesMarkdown":"It carries four normally-open instantaneous contacts, rated for 10 A at 24 V and derated to 1 A at 690 V — so the same block handles 24 VDC PLC outputs and 400 VAC interposing relays without a separate contactor for each voltage level. The 220 VDC coil pulls 3.2 W closing and holding, which means the coil driver sees a steady resistive load, not an inductive spike on dropout. The 45 mm width and 60 mm height keep it within the S00 footprint, so it slots next to a 3RT2 contactor in a standard motor starter lineup without extra spacing. ## Contact ratings and switching reliability The four NO contacts are rated for conventional free-air thermal current (Ith) across several voltage bands: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, 2 A at 500 V, and 1 A at 690 V. For the 110 V and 220 V DC control circuits, the ratings drop to 1 A and 0.27 A respectively — a reminder that DC arc extinction is harder than AC, so if you're switching a 220 VDC solenoid, stay under 0.27 A or add a flyback diode. The contact reliability spec calls out one incorrect switching operation per 100 million at 17 V, 1 mA, which is the dry-circuit threshold for PLC input signals; below that, gold-plated contacts would be safer.","metaTitle":"Siemens 3RH1140-2BM40 SIRIUS Auxiliary Contactor, 4 NO, 220","metaDescription":"Siemens SIRIUS 3RH1140-2BM40 auxiliary contactor, size S00, 4 NO contacts, 220 VDC coil, IP20 front, screw/snap-on mount, RoHS compliant. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"73 mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"45 mm","Height":"60 mm","Rated Value":"220 V","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Leading Contact":"0","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-55 ... +80 °C","Fastening Method":"screw and snap-on mounting","Full-Scale Value":"1.1","Shock Resistance":"10g / 5 ms and 5g / 10 ms","Delayed Switching":"0","Lagging Switching":"0","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","Product Brand Name":"SIRIUS","Contact Reliability":"one incorrect switching operation of 100 million switching operations (17 V, 1 mA)","Degree Of Pollution":"3","Product Designation":"Auxiliary contactor","at 24 V rated value":"10 A","Of Contactor Typical":"30 000 000","at 110 V rated value":"1 A","at 220 V rated value":"0.27 A","at 230 V rated value":"6 A","at 400 V rated value":"3 A","at 500 V rated value":"2 A","at 690 V rated value":"1 A","Instantaneous Contact":"4","For Auxiliary Contacts":"0","Make-Before-Break Switching":"0","Substance Prohibitance (Date)":"07/01/2006","protection class IP on the front":"IP20","Product Extension Auxiliary Switch":"Yes","closing power of magnet coil at DC":"3.2 W","holding power of magnet coil at DC":"3.2 W","Surge Voltage Resistance Rated Value":"6 kV","at AWG cables for auxiliary contacts":"2x (24 ... 14)","operational current at AC-12 maximum":"10 A","reference code according to IEC 81346-2":"K","Finely Stranded With Core End Processing":"2x (0.25 ... 1.5 mm²)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Touch Protection Against Electrical Shock":"finger-safe","with low demand rate according to SN 31920":"40 %","Finely Stranded Without Core End Processing":"2x (0.25 ... 2.5 mm²)","Of Auxiliary Contacts Instantaneous Contact":"0","with high demand rate according to SN 31920":"75 %","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"4","Type Of Voltage Of The Control Supply Voltage":"DC","Identification Number And Letter For Switching Elements":"40 E","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Required Spacing With Side-By-Side Mounting At The Side":"0 mm","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","Type Of Electrical Connection For Auxiliary And Control Circuit":"Cage Clamp 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"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=53194&mlfb=3RH1140-2BM40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1140-2BM40/alternatives.json"},"ai":{"faq":[{"question":"What is 3RH1140-2BM40's depth?","answer":"The depth is 73 mm."},{"question":"What wire size does 3RH1140-2BM40 accept for auxiliary contacts?","answer":"It accepts 2x (0.25... 2.5 mm²) solid or stranded wire, or 2x (24... 14) AWG."},{"question":"Will 3RH1140-2BM40 drop into a panel specified for 3RH2140-1BP40?","answer":"Both are size S00 auxiliary contactors with screw/snap-on DIN rail mounting, so the footprint and mounting are the same. The 3RH1140-2BM40 carries 4 NO contacts versus the 3RH2140-1BP40's different contact arrangement — check your control schematic for contact count and polarity before swapping."},{"question":"Where can I buy 3RH1140-2BM40?","answer":"We source this active Siemens SIRIUS part to order against an RFQ. Submit your quantity and target delivery, and we'll confirm current pricing and lead time at quote."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1140-2BM40","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/3RH1140-2BM40 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}}