{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1921-1CA01-ZX95","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1921-1CA01-ZX95","canonicalUrl":"https://aoctrl.com/siemens/3RH1921-1CA01-ZX95","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1921-1CA01-ZX95","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS, auxiliary switch block, 1 NC, screw-type terminals, 10 A rated, for 3RT1 contactors, 10 mm wide, IP20 front.","salesMarkdown":"The Siemens SIRIUS 3RH1921-1CA01-ZX95 is a front-side auxiliary switch block carrying one normally-closed (NC) contact, terminated with screw-type terminals, and designed to snap onto 3RT1 contactors and contactor relays. Its 10 mm width and 51 mm depth fit the standard SIRIUS footprint, so it mounts flush alongside the contactor without stealing extra DIN-rail space. The contact is rated 10 A maximum, but the real-world switching capacity depends on voltage and duty. At 24 V it handles 10 A (resistive) or 6 A (AC-15 inductive); at 230 V it still carries 6 A, dropping to 3 A at 400 V. The AC-15 rating at 690 V is 1 A — that governs the inductive load curve for contactor coils and small solenoid valves at higher voltages. For DC switching, the 24 V rating is 6 A, 110 V drops to 1 A, and 220 V to 0.3 A. The 6 kV surge voltage resistance and 690 V rated insulation voltage (pollution degree 3) mean this block is rated for the same panel voltage class as the 3RT1 contactor it mounts on. ## Panel integration Snap-on mounting to the 3RT1 contactor — no DIN rail required for the switch itself, though the contactor occupies the DIN rail. The 10 mm width means a full auxiliary block stack (up to four blocks) adds only 40 mm to the contactor's width. Screw terminals accept 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) with core-end processing, or 2x (20 to 16) and 2x (18 to 14) AWG. IP20 front protection is standard for the panel interior.","metaTitle":"Siemens SIRIUS 3RH1921-1CA01-ZX95 Auxiliary Switch, 1 NC, 10","metaDescription":"Siemens SIRIUS 3RH1921-1CA01-ZX95 front-side auxiliary switch, 1 NC contact, screw terminals, 10 A rated. For 3RT1 contactors. Active production. Quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Note":"with 3RT1","Depth":"51 mm","Width":"10 mm","Height":"38 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":"0","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 cables 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","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"}},"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=299323&mlfb=3RH1921-1CA01-ZX95","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RH1921-1CA01-ZX95/alternatives.json"},"ai":{"faq":[{"question":"What is the 3RH1921-1CA01-ZX95 used for?","answer":"It is a front-side auxiliary switch block with one NC contact, used with Siemens SIRIUS 3RT1 contactors and contactor relays to add a normally-closed auxiliary circuit."},{"question":"Where can I buy 3RH1921-1CA01-ZX95 and how is it quoted?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"What does the note 'with 3RT1' mean?","answer":"It means this auxiliary switch block is designed to mount directly onto Siemens SIRIUS 3RT1 series contactors and contactor relays."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1921-1CA01-ZX95","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/3RH1921-1CA01-ZX95 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}}