{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA9012-5AU21","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA9012-5AU21","canonicalUrl":"https://aoctrl.com/siemens/3RA9012-5AU21","factsUrl":"https://aoctrl.com/api/mcp/products/3RA9012-5AU21","rawCanonicalId":null},"summary":{"shortDescription":"Siemens 3RA9012-5AU21 reversing contactor, 3-pole, 2NO-2NC auxiliary contacts per coil, built-in coil suppressor, 24 VDC coil, 40 A rated.","salesMarkdown":"## Reversing contactor build — what the description tells a panel builder The 3RA9012-5AU21: This is a 3-pole reversing contactor assembly with 2NO-2NC auxiliary contacts per contactor, a built-in coil suppressor, and a 24 VDC coil rated at 40 A. The reversing pair means two contactors mechanically interlocked — one for forward, one for reverse — so both cannot close simultaneously. The 2NO-2NC aux contacts per coil give four spare signal poles for status feedback or interlocking in the control circuit. The coil suppressor is integrated, so no external flyback diode or RC snubber is needed across the 24 VDC coil — saves a DIN-rail component and a wiring step. ## Lifecycle status — active production, no replacement needed For contract manufacturing, this sits on the customer's AVL as a Siemens-specified reversing contactor — no deviation needed unless the AML explicitly lists an alternate. No stock-holding claim — each order is quoted per the customer's requested volume and delivery window.","metaTitle":"Siemens 3RA9012-5AU21 Reversing Contactor, 24 VDC, 40 A","metaDescription":"Siemens 3RA9012-5AU21 reversing contactor, 3-pole, 2NO-2NC aux contacts, coil suppressor, 24 VDC, 40 A. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"lifecycle_stage":"current"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/cee68187496abb5d1858f09afb7932b5.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=368021&mlfb=3RA9012-5AU21","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RA9012-5AU21/alternatives.json"},"ai":{"faq":[{"question":"What does the description GM-SET / ITEM NUMBER 11858 mean for this part?","answer":"The description identifies this as a Siemens reversing contactor set (item number 11858), 3-pole, with 2NO-2NC auxiliary contacts per contactor, a built-in coil suppressor, a 24 VDC coil, and a 40 A rating. The GM-SET designation indicates it is a factory-assembled reversing pair, not two loose contactors."},{"question":"What compliance documentation does Siemens provide for 3RA9012-5AU21?","answer":"Standard Siemens motor starters typically carry CE and UL markings; confirm the specific declaration with the order documentation at RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA9012-5AU21","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/3RA9012-5AU21 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}}