{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV1901-1B","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV1901-1B","canonicalUrl":"https://aoctrl.com/siemens/3RV1901-1B","factsUrl":"https://aoctrl.com/api/mcp/products/3RV1901-1B","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RV1901-1B lateral auxiliary switch, 2 NO contacts, screw-type terminals, 9.5 mm wide, for circuit breaker sizes S00 to S3.","salesMarkdown":"The Siemens SIRIUS 3RV1901-1B is a lateral auxiliary switch that clips onto the side of SIRIUS 3RV circuit breakers in frame sizes S00, S0, S2, and S3. It gives you two normally-open (2 NO) instantaneous contacts for signaling the breaker's tripped or closed state back to a PLC or indicator lamp — no contactor or separate relay needed to mirror the breaker position. ## Switching capacity and what those current ratings mean The contacts are rated for 10 A maximum, but that's the thermal current — the real-world switching capacity depends on voltage and load type. At 24 V you get 2 A; at 110 V it drops to 0.5 A; at 230 V it's 4 A; at 400 V it's 3 A; and at 690 V it's 10 A. The AC-15 rating at 690 V is 1 A, which is the inductive load curve for solenoid or contactor coils at that voltage. For a control transformer or resistive load, use the higher thermal numbers; for a motor contactor coil at 400 V, stay within the 3 A AC-15 curve. ## Mounting and wiring — fits the panel, not the rail This switch uses plug-in fixing — it snaps onto the side of the breaker, not onto a DIN rail. That's the lateral design: it adds width to the breaker assembly without eating up rail space. The 9.5 mm width means it tucks in tight alongside the breaker. Wiring is via screw-type terminals; the clamping range accepts 2x (0.5 to 1.5 mm²) solid or 2x (0.75 to 2.5 mm²) stranded per terminal, which covers most control-circuit runs. Strip length and torque follow standard Siemens terminal practice for this class. ## Environmental limits and compliance No UL or CSA listing is stated in the available documentation; the part carries Siemens SIRIUS branding and is designed to IEC/EN standards for the 3RV breaker family. Compliance documentation (RoHS, REACH) is standard for current Siemens industrial control products.","metaTitle":"Siemens 3RV1901-1B SIRIUS Auxiliary Switch, 2 NO, Lateral, 1","metaDescription":"Siemens SIRIUS 3RV1901-1B lateral auxiliary switch, 2 NO contacts, rated 10A max. Phased-out; successor 3RV2901-1B. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Protection Circuit Breakers (MPCB)"],"specifications":{"Depth":"70mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Width":"9.5mm","Height":"90mm","Maximum":"10A","at 24 V":"2A","at 110 V":"0.5A","at 220 V":"0.25A","at 230 V":"4A","at 400 V":"3A","at 690 V":"10A","During Storage":"-50 ... +80°C","lifecycle_stage":"current","During Operation":"-20 ... +60°C","Fastening Method":"plug-in fixing","Product Brand Name":"SIRIUS","Product Designation":"auxiliary switch, lateral","Design Of The Product":"lateral auxiliary switches","With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Size Of The Circuit-Breaker":"S00, S0, S2, S3","at AC-15 at 690 V rated value":"1A","at AWG cables for auxiliary contacts":"2x (18 ... 14)","Type Of Electrical Connection For Auxiliary And Control Circuit":"screw-type terminals","number of CO contacts of auxiliary contacts instantaneous contact":"0","number of NC contacts for auxiliary contacts instantaneous contact":"0","number of NO contacts for auxiliary contacts instantaneous contact":"2"}},"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=205288&mlfb=3RV1901-1B","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RV1901-1B/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RV1901-1B?","answer":"We source the phased-out 3RV1901-1B to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time. For volume or scheduled purchases, the successor 3RV2901-1B is the recommended ordering code."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV1901-1B","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/3RV1901-1B 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}}