{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1911-1LA20","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1911-1LA20","canonicalUrl":"https://aoctrl.com/siemens/3RH1911-1LA20","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1911-1LA20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS auxiliary switch block, 3RH1911-1LA20, 2 NO contacts, screw terminals, snap-on mounting for size S00 contactors, 10 A max.","salesMarkdown":"It snaps onto the front of the contactor without tools — no extra DIN rail space needed, just a firm push until the latch clicks. Switching capacity depends on the circuit voltage: rated for 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V. At 690 V in AC-15 duty it handles 1 A. Dimensions: 36.5 mm wide, 37.5 mm tall, 41.5 mm deep — compact enough to fit inside a shallow gland plate or behind a panel door without crowding adjacent devices. The snap-on mount engages the contactor's front profile, so the contactor's own DIN-rail footprint stays unchanged. Terminals are screw-type, accepting 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) with core-end processing, or the AWG equivalents 2x (20 to 16) and 2x (18 to 14). Strip length and torque follow standard Siemens S00 practice — no special tooling needed. ## Contact reliability and service life Rated for 10 million mechanical switching cycles typical. The same reliability spec applies at 1 mA for the auxiliary contacts, so it handles PLC-level signals without the usual wetting-current worry. ## Environmental and protection Surge voltage resistance rated at 6 kV, which is standard for industrial control circuits running alongside contactors and drives.","metaTitle":"Siemens 3RH1911-1LA20 Auxiliary Switch Block, 2 NO, 10 A, S0","metaDescription":"Siemens SIRIUS 3RH1911-1LA20 auxiliary switch block, 2 NO contacts, 10 A max, snap-on mount for S00 contactors. Phased out; successor 3RH2911-1LA20 available. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Note":"with 3RH1","Depth":"41.5 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","Mounting type":"snap-on mounting","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Product brand name":"SIRIUS","Contact reliability":"one incorrect switching operation of 100 million switching operations (17 V, 5 mA)","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":"2","With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 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 conductors for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14)","Contact reliability of auxiliary contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Mechanical service life (switching cycles) typical":"10 000 000","Insulation voltage with degree of pollution 3 rated value":"690 V","Type of electrical connection for auxiliary and control current circuit":"screw-type terminals"}},"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=258901&mlfb=3RH1911-1LA20","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1911-1LA20/alternatives.json"},"ai":{"faq":[{"question":"What replaces 3RH1911-1LA20?","answer":"The official successor is the SIRIUS 3RH2911-1LA20. It performs the same function — 2 NO auxiliary contacts, screw terminals, snap-on mount for size S00 contactors — and should be a drop-in fit for new builds."},{"question":"Will 3RH1911-1LA20 fit a panel designed for 3RH2122-1WB40?","answer":"No, not without rewiring. The 3RH2122-1WB40 is a physically larger coupling relay (73 mm deep, 45 mm wide) with a different mounting footprint and a built-in varistor. The 3RH1911-1LA20 is a compact auxiliary switch block that snaps onto a size S00 contactor — it's a different form factor and wiring layout."},{"question":"Where can I buy 3RH1911-1LA20?","answer":"We source it through independent distribution and quote it to order against an RFQ. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1911-1LA20","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/3RH1911-1LA20 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}}