{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA1921-2F","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA1921-2F","canonicalUrl":"https://aoctrl.com/siemens/3RA1921-2F","factsUrl":"https://aoctrl.com/api/mcp/products/3RA1921-2F","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS hybrid link module, size S00, for 3RV1.2 screw system and 3RT1.1 spring-type contactors, phased-out product.","salesMarkdown":"## What this part does in the panel The Siemens 3RA1921-2F is a SIRIUS hybrid link module that provides the mechanical and electrical interconnection between a 3RV1.2 circuit breaker (size S0, screw-type terminals) and a 3RT1.1 contactor (size S00, spring-type terminals). It replaces the need for separate wiring between the breaker and contactor, saving panel space and reducing assembly time on a DIN-rail motor starter assembly. ## Lifecycle reality — this is a phased-out part The 3RA1921-2F is officially a phased-out product. The manufacturer lists the preferred successor as the SIRIUS 3RA2921-2F. If you are filling a BOM line or stocking spares for an existing panel design, the 3RA2921-2F is the drop-in replacement to specify going forward. This module is designed for the 3RV1.2 screw-type circuit breaker (size S0) and the 3RT1.1 spring-type contactor (size S00). It physically bridges the two devices, aligning the breaker output terminals with the contactor input terminals. The contactor size is S00, meaning it handles motor loads up to about 7.5 kW at 400 V AC-3 (typical for a 3RT1.1 contactor in that frame). The circuit-breaker size is S0, which covers the upstream protection range for that contactor class.","metaTitle":"Siemens 3RA1921-2F SIRIUS Hybrid Link Module, Phased Out","metaDescription":"Siemens 3RA1921-2F SIRIUS hybrid link module for 3RV1.2 screw system and 3RT1.1 contactors. Phased-out product; official successor is 3RA2921-2F.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"lifecycle_stage":"current","Size Of Contactor":"S00","Product Brand Name":"SIRIUS","Product Designation":"hybrid link module","Design Of The Product":"for 3RV1.2 screw system and 3RT1.1","Size Of The Circuit-Breaker":"S0"}},"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=443035&mlfb=3RA1921-2F","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RA1921-2F/alternatives.json"},"ai":{"faq":[{"question":"Is 3RA1921-2F obsolete?","answer":"Yes, the 3RA1921-2F is a phased-out product. The official successor is the SIRIUS 3RA2921-2F. We source the original 3RA1921-2F to order against an RFQ through independent distribution channels."},{"question":"What is the replacement for 3RA1921-2F?","answer":"The preferred successor is the SIRIUS 3RA2921-2F. It is the direct replacement for this hybrid link module and should be specified for new builds or when replacing a failed unit."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA1921-2F","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/3RA1921-2F 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}}