{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA1943-2A","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA1943-2A","canonicalUrl":"https://aoctrl.com/siemens/3RA1943-2A","factsUrl":"https://aoctrl.com/api/mcp/products/3RA1943-2A","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RA1943-2A wiring kit, for reversing starter Size S3, 3-pole, product phase-out with successor 3RA2943-2AA1.","salesMarkdown":"The 3RA1943-2A is a SIRIUS wiring kit that provides the electrical and mechanical interconnection for a reversing starter built on a Size S3 contactor frame. It handles the cross-wiring between the forward and reverse contactors so the reversing starter functions as a single assembly. This part is in product phase-out. The preferred successor is the SIRIUS 3RA2 series order code 3RA2943-2AA1, which replaces the 3RA1943-2A in new builds and service replacements. ## Phase-out reality and the successor path The official successor is the 3RA2943-2AA1 from the SIRIUS 3RA2 family. For BOM lines still specifying the 3RA1943-2A, the 3RA2943-2AA1 is the drop-in replacement from Siemens. Verify the mounting footprint and wiring scheme against your panel layout before committing the change. ## Poles and contactor frame size The kit is designed for a 3-pole reversing starter configuration on a Size S3 contactor frame. The S3 frame is the medium-duty size in the SIRIUS contactor range, typically used for motors in the 15–30 kW range depending on duty cycle and voltage. It eliminates point-to-point wiring errors between the two contactors.","metaTitle":"Siemens 3RA1943-2A SIRIUS Wiring Kit, S3 Reversing Starter","metaDescription":"Siemens 3RA1943-2A SIRIUS wiring kit for S3 reversing starters. Product phase-out with official successor 3RA2943-2AA1. 3 poles. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"title":"3RA1943-2A","description":"Wiring kit Electrical and mechanical for reversing starter, Size S3!!! Product phase-out!!! Successor is SIRIUS 3RA2 Preferred successor type is >>3RA2943-2AA1<<","Number Of Poles":"3","lifecycle_stage":"current","Size Of Contactor":"S3","Product Brand Name":"SIRIUS","Product Designation":"Wiring kit","Design Of The Product":"for reversing starter S3","Substance Prohibitance (Date)":"07/01/2006"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/292c2fcd3844d05985616c3f9f7e235a.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=127209&mlfb=3RA1943-2A"},"ai":{"faq":[{"question":"What is the closest alternative to 3RA1943-2A in the SIRIUS family?","answer":"The direct replacement is the 3RA2943-2AA1. It is the preferred successor type from the SIRIUS 3RA2 series and serves the same S3 reversing starter application. No pin-compatible alternative outside the SIRIUS family is documented by Siemens."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA1943-2A","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/3RA1943-2A 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}}