{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1945-5AP01","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1945-5AP01","canonicalUrl":"https://aoctrl.com/siemens/3RT1945-5AP01","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1945-5AP01","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1945-5AP01 magnet coil, size S3, screw terminal, 230 V AC 50 Hz, phased-out product with official SIRIUS 3RT2 successor.","salesMarkdown":"The Siemens 3RT1945-5AP01 is a SIRIUS-branded magnet coil, the electromagnetic actuator that pulls in the contactor armature when energized. It is sized for SIRIUS size S3 contactors and terminates via screw terminals. The control voltage is 230 V AC at 50 Hz, with an operating range of 0.8 to 1.1 times that nominal voltage — meaning the coil will reliably pick up between roughly 184 V and 253 V AC, and will hold in down to about 184 V. This is the replacement coil for a failed or missing coil on an existing S3 contactor, not a standalone contactor itself. This part is a phased-out product. The manufacturer's official successor is the SIRIUS 3RT2 series. If your design is still open, the 3RT2 series is the direct replacement path; if you are repairing an existing S3 contactor panel, the 3RT1945-5AP01 remains available through the surplus and broker network. This coil mounts directly onto SIRIUS size S3 contactor frames. The screw terminals accept the same wiring as the original coil — no adapter or re-termination needed. It is a drop-in swap for an existing S3 contactor that has lost its coil or needs a different control voltage. The coil's operating range (0.8 to 1.1 x 230 V AC) means it will function correctly on a 230 V AC control circuit with typical voltage sag, but verify your control transformer is sized for the inrush (pick-up) VA of the coil — the S3 coil draw is higher than the S00 or S0 sizes.","metaTitle":"Siemens 3RT1945-5AP01 SIRIUS Magnet Coil, 230 V AC 50 Hz, Ph","metaDescription":"Siemens 3RT1945-5AP01 SIRIUS magnet coil for size S3 contactors, 230 V AC 50 Hz. Phased-out product; official successor is the SIRIUS 3RT2 series. Sourced to order against RFQ.","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":"230 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=211078&mlfb=3RT1945-5AP01","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1945-5AP01/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RT1945-5AP01 and how do I get a price?","answer":"This part is sourced through independent distribution channels. Submit an RFQ for current availability and pricing — it is quoted to order, with confirmation at quote time. No stock figures or prices are published here."},{"question":"What is the closest functional second-source for 3RT1945-5AP01?","answer":"The manufacturer's official successor is the SIRIUS 3RT2 series. For a drop-in replacement on an existing S3 contactor, the 3RT1945-5AP01 itself is the correct coil — the 3RT2 series uses a different coil part number and may require a different contactor frame. If you are repairing an S3 panel, source the 3RT1945-5AP01; if designing new, move to the 3RT2 series."},{"question":"What is the operating voltage range for 3RT1945-5AP01?","answer":"The coil is rated for 230 V AC at 50 Hz, with an operating range of 0.8 to 1.1 times nominal — so it will pick up and hold between approximately 184 V and 253 V AC."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1945-5AP01","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/3RT1945-5AP01 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}}