{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH1921-1EA02-ZX90","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH1921-1EA02-ZX90","canonicalUrl":"https://aoctrl.com/siemens/3RH1921-1EA02-ZX90","factsUrl":"https://aoctrl.com/api/mcp/products/3RH1921-1EA02-ZX90","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RH1921-1EA02-ZX90 auxiliary switch, 10 A rated operational current, snap-on mounting for S0 contactor size, 10 mm width, screw-type terminals.","salesMarkdown":"## What this auxiliary switch does on a contactor The 3RH1921-1EA02-ZX90 is a SIRIUS auxiliary switch block that snaps onto the side of an S0-size contactor or contactor relay — it adds extra signal contacts without widening the main power path. The block is 10 mm wide — it adds minimal DIN-rail footprint when side-mounted, and the IP20 front protection means it's safe for open-panel use behind a cabinet door. Snap-on mounting to the contactor side — no DIN-rail slot consumed, but the block adds 10 mm to the assembly width. The mirror contact feature per IEC 60947-4-1 is present when paired with a 3RT1 contactor — this matters for safety circuits where the N/C contact must positively indicate the main contact position. ## Environmental and compliance envelope RoHS compliance date is July 1, 2006 — the part meets the original RoHS directive; verify REACH and UKCA status against the current Siemens declaration pack for your jurisdiction.","metaTitle":"Siemens 3RH1921-1EA02-ZX90 SIRIUS Auxiliary Switch, 10 A","metaDescription":"Siemens 3RH1921-1EA02-ZX90 SIRIUS auxiliary switch, 10 A rated current, 10 mm width, snap-on mounting for S0 contactors. Active production, quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"71 mm","Width":"10 mm","title":"3RH1921-1EA02-ZX90","Height":"80 mm","at 24 V":"6 A","at 48 V":"2 A","at 60 V":"2 A","at 110 V":"1 A","at 125 V":"0.9 A","at 220 V":"0.3 A","at 230 V":"6 A","at 250 V":"0.3 A","at 400 V":"3 A","description":"first lateral auxiliary switch 2 NC contacts, screw terminal, for contactors 3RT1 Reusable packaging = 144 units","During Storage":"-55 ... +80 °C","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"snap-on mounting","Product Category":"Auxiliary switch","Size Of Contactor":"S0","Solid Or Stranded":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Product Designation":"auxiliary switch","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","Design Of The Product":"first laterally mountable","Instantaneous Contact":"0","Substance Prohibitance (Date)":"07/01/2006","protection class IP on the front":"IP20","Surge Voltage Resistance Rated Value":"6 kV","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14)","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)","mirror contact according to IEC 60947-4-1":"Yes; with 3RT1","Mechanical Service Life (Operating Cycles) Typical":"10 000 000","operational current of auxiliary contacts at AC-12 maximum":"10 A","Type Of Electrical Connection For Auxiliary And Control Circuit":"screw-type terminals","insulation voltage with degree of pollution 3 at AC rated value":"500 V","number of CO contacts of auxiliary contacts instantaneous contact":"0","AWG number as coded connectable conductor cross section for auxiliary contacts":"20 ... 14"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/5f066901d27f3d64b66f6fcbf313f70c.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=195413&mlfb=3RH1921-1EA02-ZX90"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH1921-1EA02-ZX90","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/3RH1921-1EA02-ZX90 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}