{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1945-5AG61","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1945-5AG61","canonicalUrl":"https://aoctrl.com/siemens/3RT1945-5AG61","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1945-5AG61","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS magnet coil, 100 V AC at 50 Hz / 110 V AC at 60 Hz, for Size S3 contactors, screw terminal, phased-out product.","salesMarkdown":"The Siemens 3RT1945-5AG61 is a SIRIUS magnet coil designed for Size S3 contactors. ## Sourcing reality — phased out with a clear path This coil is a phased-out product. The official successor is the SIRIUS 3RT2 series. There is no last-time-buy window; the part is already in the phase-out lifecycle stage. ## What the control voltage ratings mean for fit That 10 V difference compensates for the higher impedance at 60 Hz, so the magnetic pull-in force stays consistent across line frequencies. If your panel runs 110 V AC at 60 Hz, this coil matches. If you have a 100 V AC 50 Hz supply, it also matches. The operating range of 0.8 to 1.1 times the rated voltage at 50 Hz means the coil will pick up reliably between 80 V and 110 V AC. ## Integration note — Size S3 footprint This coil mounts onto SIRIUS Size S3 contactors. The screw terminals accept the same wire ranges as the contactor's auxiliary circuit — typically 2x (0.5 to 1.5 mm²) solid or stranded. The coil draws its rated control voltage from the panel's AC control transformer; no DC rectification needed since it's an AC coil.","metaTitle":"Siemens 3RT1945-5AG61 SIRIUS Magnet Coil, 100 V AC 50/60 Hz","metaDescription":"Siemens 3RT1945-5AG61 SIRIUS magnet coil for Size S3 contactors. 100 V AC at 50 Hz, 110 V AC at 60 Hz. Phased-out product; successor is SIRIUS 3RT2 series. Sourced to order against","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"at 50 Hz":"0.8 ... 1.1","lifecycle_stage":"current","Product Brand Name":"SIRIUS","Product Designation":"Magnet coil","at 50 Hz rated value":"100 V","at 60 Hz rated value":"110 V","Type Of Voltage Of The Control Supply Voltage":"AC"}},"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=530479&mlfb=3RT1945-5AG61","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1945-5AG61/alternatives.json"},"ai":{"faq":[{"question":"Will the 3RT1945-5AG61 fit a panel designed for the 3RT7036-1AG20?","answer":"Both coils are for SIRIUS contactors, but the 3RT7036-1AG20 is a Size S2 coil, while the 3RT1945-5AG61 is Size S3. The physical dimensions and mounting points differ — they are not drop-in interchangeable without changing the contactor frame."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1945-5AG61","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/3RT1945-5AG61 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}}