{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1911-2FA40-0MC0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1911-2FA40-0MC0","canonicalUrl":"https://aoctrl.com/siemens/3RH1911-2FA40-0MC0","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1911-2FA40-0MC0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS auxiliary switch block, 4 NO, 10 A, spring-loaded terminals, snap-on mounting, IP20 front, 46 × 36.5 × 37.5 mm.","salesMarkdown":"## Auxiliary Switch Block for SIRIUS Contactors The Siemens 3RH1911-2FA40-0MC0 is a SIRIUS auxiliary switch block that mounts on the front of 3RT101..-.K...-0LA0 contactors, adding four normally-open (4 NO) instantaneous contacts rated 10 A maximum. The 10 A maximum is a thermal (AC-1) rating; the real-world switching capacity depends on voltage and load type. At 24 V it handles 6 A, at 230 V it handles 6 A, and at 400 V it handles 3 A. For DC loads the derating is steeper: 6 A at 24 V, 2 A at 60 V, 0.3 A at 220 V. The AC-15 rating at 690 V is 1 A — that's the inductive pilot-duty limit for solenoid valves or contactor coils in a 690 V control circuit. Four NO contacts means this block provides four independent form-A (normally-open) switching channels. The insulation voltage is 690 V at pollution degree 3, with a surge withstand of 6 kV, which covers most industrial control panels up to 480/690 V line-to-line. Dimensions are 46 mm deep, 36.5 mm wide, 37.5 mm high — it adds about 37 mm of height to the contactor stack. Spring-loaded terminals accept 2× (0.5 to 2.5 mm²) without ferrules, or 2× (0.5 to 1.5 mm²) with core-end processing. AWG range is 2× (20 to 14).","metaTitle":"Siemens 3RH1911-2FA40-0MC0 SIRIUS Auxiliary Switch, 4 NO, 10","metaDescription":"Siemens SIRIUS 3RH1911-2FA40-0MC0 auxiliary switch block, 4 NO contacts rated 10 A, spring-loaded terminals, snap-on DIN rail mount, IP20 front. Active production.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"46 mm","Width":"36.5 mm","Height":"37.5 mm","Maximum":"10 A","at 24 V":"6 A","at 60 V":"2 A","at 110 V":"1 A","at 125 V":"6 A","at 220 V":"0.3 A","at 230 V":"6 A","at 250 V":"6 A","at 400 V":"3 A","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"snap-on mounting","Product Brand Name":"SIRIUS","Suitability For Use":"Contactor relay and power contactor","at 24 V rated value":"10 A","at 60 V rated value":"4.7 A","at 110 V rated value":"3 A","at 220 V rated value":"1.2 A","at 440 V rated value":"0.5 A","at 600 V rated value":"0.26 A","Instantaneous Contact":"4","With Core End Processing":"2x (0.5 ... 1.5 mm²)","Without Core End Processing":"2x (0.5 ... 2.5 mm²)","at AC-15 at 690 V rated value":"1 A","protection class IP on the front":"IP20","Surge Voltage Resistance Rated Value":"6 kV","at AWG cables for auxiliary contacts":"2x (20 ... 14)","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Mechanical Service Life (Operating Cycles) 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"}},"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=1458568&mlfb=3RH1911-2FA40-0MC0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1911-2FA40-0MC0/alternatives.json"},"ai":{"faq":[{"question":"What are the key ratings for this auxiliary switch?","answer":"Maximum 10 A thermal. At 230 V AC it switches 6 A; at 400 V AC it switches 3 A. DC ratings: 6 A at 24 V, 2 A at 60 V, 0.3 A at 220 V. AC-15 at 690 V is 1 A. Four NO contacts, spring-loaded terminals, IP20 front, snap-on DIN rail mount."},{"question":"What contactor does this auxiliary switch fit?","answer":"It mounts on the front of Siemens SIRIUS 3RT101..-.K...-0LA0 contactors. The 4 NO contacts are wired as 53/54, 63/64, 73/74, 83/84."},{"question":"Will the 3RH1911-2FA40-0MC0 drop into a panel built for a 3RT5064-6AP36-0TH0 contactor?","answer":"No — the 3RT5064-6AP36-0TH0 is a power contactor in a different frame size (110 kW at 400 V). The 3RH1911-2FA40-0MC0 is a front-mounted auxiliary block for the smaller 3RT101..-.K...-0LA0 frame. They are not mechanically interchangeable without rewiring the contactor base."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1911-2FA40-0MC0","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/3RH1911-2FA40-0MC0 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}}