{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1140-1BG40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1140-1BG40","canonicalUrl":"https://aoctrl.com/siemens/3RH1140-1BG40","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1140-1BG40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS auxiliary contactor, size S00, 4 NO instantaneous contacts, 125 V DC coil, 45 mm width, screw and snap-on mounting, IP20 front.","salesMarkdown":"The Siemens 3RH1140-1BG40 is a SIRIUS auxiliary contactor in the size S00 frame — the compact footprint that mates directly with S00 power contactors on a DIN rail. It carries 4 instantaneous normally-open contacts, rated for a 125 V DC coil. The 45 mm width and 72 mm depth match the standard S00 contactor envelope, so it clips onto the same rail alongside the main contactor without extra panel space. This is the auxiliary block you add when the main contactor runs out of N.O. aux contacts — or when you need a separate control-circuit isolation path. The coil draws 3.2 W DC both on pick-up and hold, so the control transformer sizing is straightforward: no inrush spike to budget for. The contacts are rated for switching at several common control voltages: 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. These are thermal current ratings for the auxiliary contacts — they govern the continuous current the contacts can carry, not the motor load. For a typical 24 V DC PLC output driving a solenoid or indicator, 10 A is generous headroom. At 230 V AC control circuits, 6 A covers most pilot-duty loads. ## Mechanical endurance and mounting flexibility Typical mechanical life is 30 million switching operations. Contact reliability is specified as one incorrect switching operation per 100 million at 17 V and 1 mA — that low-level switching capability matters when the auxiliary contacts are used to read dry-contact status inputs from sensors or limit switches. Shock resistance is 10g for 5 ms and 5g for 10 ms, covering most industrial vibration environments short of direct hammer strikes. Terminals accept solid conductors: 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm². That covers standard control wiring from 18 AWG to 12 AWG. The screw-clamp terminals are the same type used on S00 contactors, so the same screwdriver and torque setting apply across the panel. RoHS compliance date is 2006-07-01, covering the EU RoHS directive.","metaTitle":"Siemens 3RH1140-1BG40 SIRIUS Auxiliary Contactor, 4 NO, 125","metaDescription":"Siemens 3RH1140-1BG40 SIRIUS auxiliary contactor, size S00, 4 instantaneous NO contacts, 125 V DC coil, 45 mm wide, IP20 front. Current production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"72 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 mm²","Width":"45 mm","Height":"57.5 mm","Rated Value":"125 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)":"01.07.2006 00:00:00","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","reference code acc. to IEC 81346-2":"K","Surge Voltage Resistance Rated Value":"6 kV","at AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","operational current at AC-12 maximum":"10 A","with low demand rate acc. to SN 31920":"40 %","with high demand rate acc. to SN 31920":"75 %","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Touch Protection Against Electrical Shock":"finger-safe","Of Auxiliary Contacts Instantaneous Contact":"0","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","B10 value with high demand rate acc. to SN 31920":"1 000 000; With 0.3 x Ie","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":"screw-type 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=353960&mlfb=3RH1140-1BG40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1140-1BG40/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RH1140-1BG40 and how is it quoted?","answer":"This part is sourced through independent distribution and quoted to order against an RFQ. Availability and current pricing are confirmed at quote time — no stock or price figures are published here."},{"question":"What is the closest functional second-source to 3RH1140-1BG40?","answer":"The 3RH2140-1BP40 is a peer in the same SIRIUS auxiliary contactor family, but it uses a 24 V DC coil instead of 125 V DC. The contact configuration and mechanical footprint are similar, so it can be a drop-in replacement if the control voltage matches your panel. Verify the coil voltage before ordering."},{"question":"What is the depth of 3RH1140-1BG40?","answer":"The depth is 72 mm, which matches the standard S00 contactor envelope for DIN-rail mounting."},{"question":"What solid wire sizes does 3RH1140-1BG40 accept?","answer":"The terminals accept 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm² solid conductors."},{"question":"Will 3RH1140-1BG40 drop into a panel specified around 3RH2140-1BP40 without rewiring?","answer":"Mechanically yes — both are size S00 with the same 45 mm width and DIN-rail clip. Electrically no — the 3RH1140-1BG40 has a 125 V DC coil, while the 3RH2140-1BP40 uses 24 V DC. The coil circuit would need rewiring if the panel was built for 24 V."},{"question":"What compliance documentation does Siemens provide for 3RH1140-1BG40?","answer":"RoHS compliance is confirmed with a substance prohibition date of 2006-07-01. The part carries IP20 front protection and is designed to IEC 60947 standards. For specific UL, CSA, or REACH documentation, request the manufacturer's declaration at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1140-1BG40","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/3RH1140-1BG40 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}}