{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RH2921-2DA11","brand":"Siemens","brandSlug":"siemens","productSlug":"3RH2921-2DA11","canonicalUrl":"https://aoctrl.com/siemens/3RH2921-2DA11","factsUrl":"https://aoctrl.com/api/mcp/products/3RH2921-2DA11","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RH2921-2DA11 auxiliary switch, snap-on mounting, 10 mm width, 66 mm depth, rated 6 A at 24 V, IP20 front.","salesMarkdown":"## Narrow-Profile Auxiliary Switch for SIRIUS Contactors The Siemens 3RH2921-2DA11 is a SIRIUS auxiliary switch designed for lateral mounting alongside contactor relays and power contactors in the S00, S0, S2, and S3 frame sizes. At just 10 mm wide, it fits into dense panel layouts where DIN-rail space is at a premium — the snap-on mounting lets you add auxiliary contacts without increasing the contactor's footprint beyond its own width. ## Rated Operational Current Across Voltages The 3RH2921-2DA11 carries a rated operational current of 6 A at 24 V and 230 V, 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V and 250 V, and 3 A at 400 V. ## Contact Reliability and Mirror Contact Compliance The auxiliary contacts are rated for 1 faulty switching per 100 million operations at 17 V, 1 mA — a reliability figure that supports high-cycle applications like safety circuits where missed signals are unacceptable. When paired with the 3RT2 contactor series, the 3RH2921-2DA11 provides a mirror contact per IEC 60947-4-1, meaning the normally closed contact mechanically reflects the main contact position — critical for fail-safe isolation in machinery guarding circuits. ## Physical Fit and Wiring Dimensions are 10 mm wide, 64.8 mm high, and 66 mm deep — the narrow width means you can stack multiple auxiliary switches alongside a contactor without exceeding the standard DIN-rail pitch. Terminals accept 2x (0.5 to 2.5 mm²) solid or stranded wire, or 2x (20 to 14 AWG); finely stranded wire with ferrule is limited to 2x (0.5 to 1.5 mm²). The IP20 front protection keeps fingers away from live terminals inside the enclosure.","metaTitle":"Siemens 3RH2921-2DA11 SIRIUS Auxiliary Switch, 10 mm Width","metaDescription":"Siemens 3RH2921-2DA11 SIRIUS auxiliary switch, 10 mm wide, snap-on mounting for S00-S3 contactors. Rated 6 A at 24 V, IP20 front. Current lifecycle stage.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"66 mm","Width":"10 mm","title":"3RH2921-2DA11","Height":"64.8 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":"auxiliary switch, lateral, 1 NO + 1 NC, on the left: 51/52, 63/64, on the right: 31/32, 43/44, current path: 1 NC, 1 NO, spring-loaded terminal, for contactors 3RT2 and contactor relays 3RH2","During Storage":"-55 ... +80 °C","Leading Contact":"0","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"snap-on mounting","Product Category":"Auxiliary switch","Lagging Switching":"0","Size Of Contactor":"S00, S0, S2, S3","Solid Or Stranded":"2x (0.5 ... 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","at 600 V rated value":"0.26 A","Design Of The Product":"first laterally mountable","Instantaneous Contact":"1","Substance Prohibitance (Date)":"10/01/2009","protection class IP on the front":"IP20","Surge Voltage Resistance Rated Value":"6 kV","for AWG cables for auxiliary contacts":"2x (20 ... 14)","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 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 3RT2","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","operational current at AC-15 at 690 V rated value":"1 A","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":"spring-loaded terminals","insulation voltage with degree of pollution 3 at AC rated value":"690 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/2d2d01c038bf44e269e1326f884602f9.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=332856&mlfb=3RH2921-2DA11"},"ai":{"faq":[{"question":"How can I order or check stock for 3RH2921-2DA11?","answer":"Sourced to order against your BOM quantity through independent distribution."},{"question":"What compliance documentation does Siemens provide for 3RH2921-2DA11?","answer":"The part carries a RoHS substance prohibition date of 10/01/2009, indicating RoHS compliance. The surge voltage resistance is rated at 6 kV. For full documentation (UL, IEC, REACH), request the manufacturer's declaration with your order."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RH2921-2DA11","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/3RH2921-2DA11 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}