{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1122-1MB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1122-1MB40","canonicalUrl":"https://aoctrl.com/siemens/3RH1122-1MB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1122-1MB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS coupling relay, 3RH1122-1MB40, 24 VDC coil, 2 NO contacts, 10 A rated at 24 V, size S00, screw and snap-on mounting, IP20 front.","salesMarkdown":"The Siemens SIRIUS 3RH1122-1MB40 is a coupling relay for switching auxiliary circuits, built into the S00 contactor footprint. It carries 2 normally-open instantaneous contacts, with a 24 V DC coil that picks up at 0.85 of rated voltage and drops out at 2.15 times rated — that 2.15 factor means the relay holds in through deep sags but releases decisively on undervoltage, a useful trait in control circuits where you want a clean dropout rather than a chattering contact. The contact rating is 10 A at 24 V, which is the full-load current for a 24 VDC auxiliary load — think solenoid valves, indicator lamps, or PLC input modules. At 230 V AC the contacts are rated 6 A, and at 400 V AC they drop to 3 A, so the relay can handle mixed-voltage control circuits within a panel. The 6 kV surge voltage rating (impulse withstand) covers the transient immunity required in industrial environments with motor starts and contactor switching nearby. Coil power is 1.4 W holding, same as pick-up — a DC economizer circuit is not needed here; the coil simply stays at full power. That 1.4 W is low enough to be driven by a standard 24 VDC PLC output or a small auxiliary contact without overheating the backplane. Fastening is by screw or snap-on onto a DIN rail. The S00 size — 45 mm wide, 57.5 mm tall, 72 mm deep — fits the standard contactor footprint used across the SIRIUS family, so it occupies the same slot as a 3RT2 contactor of the same frame. Front protection is IP20 — finger-safe but not washdown-rated. The relay is intended for dry indoor panels, not for hose-down or outdoor locations.","metaTitle":"Siemens 3RH1122-1MB40 SIRIUS Coupling Relay, 24 VDC, 2 NO, 1","metaDescription":"Siemens 3RH1122-1MB40 SIRIUS coupling relay, 24 VDC coil, 2 NO contacts rated 10 A at 24 V. Size S00, screw/snap-on mount, IP20. Current production. Sourced 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":"24 V","Initial Value":"0.85","During Storage":"-55 ... +80 °C","Leading Contact":"0","lifecycle_stage":"current","During Operation":"-25 ... +40 °C","During Transport":"-55 ... +80 °C","Fastening Method":"screw and snap-on mounting","Full-Scale Value":"2.15","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":"Coupling relay for switching auxiliary circuits","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":"2","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":"No","closing power of magnet coil at DC":"1.4 W","holding power of magnet coil at DC":"1.4 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":"2","number of NO contacts for auxiliary contacts":"2","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":"22 E","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Required Spacing With Side-By-Side Mounting At The Side":"0 mm","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","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=214089&mlfb=3RH1122-1MB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1122-1MB40/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RH1122-1MB40 and get a price?","answer":"This part is sourced to order through independent distribution. Submit an RFQ; availability and current pricing are confirmed at quote time."},{"question":"What is the depth of 3RH1122-1MB40?","answer":"The depth is 72 mm."},{"question":"What wire sizes does 3RH1122-1MB40 accept?","answer":"It accepts solid conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), and 2x 4 mm²."},{"question":"Will 3RH1122-1MB40 drop into a panel specified around 3RH2122-1WB40?","answer":"Both are S00 frame size with the same DIN-rail footprint (45 mm width, 57.5 mm height, 72 mm depth), so the mechanical fit is identical. The difference is coil voltage: 3RH1122-1MB40 uses 24 VDC, while 3RH2122-1WB40 uses a different coil voltage — verify the control circuit before substituting."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1122-1MB40","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/3RH1122-1MB40 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}}