{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1934-5BM42","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1934-5BM42","canonicalUrl":"https://aoctrl.com/siemens/3RT1934-5BM42","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1934-5BM42","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS, magnet coil for Size S2 contactors, 3RT1934-5BM42, 220 V DC, spring-loaded connection, phased-out product.","salesMarkdown":"The Siemens SIRIUS 3RT1934-5BM42 is a 220 V DC magnet coil intended for Size S2 contactors. It uses spring-loaded connection technology, so wiring lands without screw terminals — just strip, insert, release. This is the replacement coil if you have a Size S2 contactor body that needs a 220 V DC pull-in and hold. ## Fit and Mechanical Integration This coil is sized for the SIRIUS Size S2 contactor frame. If your panel was built around a Size S2 contactor body (e.g., 3RT10 or 3RT13 series), this coil snaps onto the magnet armature without tools. Verify the control voltage bus: 220 V DC nominal, and the coil dropout threshold is typically around 0.8× rated — so below 176 V DC the contactor drops out. That matters if your DC supply is unregulated or shared with inductive loads.","metaTitle":"Siemens 3RT1934-5BM42 SIRIUS Magnet Coil, 220 V DC","metaDescription":"Siemens SIRIUS 3RT1934-5BM42 magnet coil for Size S2 contactors. 220 V DC, spring-loaded connection. Phased-out; successor is 3RT2 series. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"lifecycle_stage":"current","Product Brand Name":"SIRIUS","1 at DC rated value":"220 V","Product Designation":"Magnet coil","Type Of Voltage Of The Control Supply Voltage":"DC"}},"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=178632&mlfb=3RT1934-5BM42","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1934-5BM42/alternatives.json"},"ai":{"faq":[{"question":"What replaces the 3RT1934-5BM42?","answer":"The official successor is the SIRIUS 3RT2 series. This is a coil for Size S2 contactors, so the replacement will be a 3RT2-series coil matched to the contactor frame size and 220 V DC control voltage."},{"question":"Does the 3RT1934-5BM42 drop into a panel built for a 3RT1015-1BB42?","answer":"No, not without rewiring. The 3RT1015-1BB42 is a complete power contactor (Size S00) with a 24 V DC coil and screw terminals. The 3RT1934-5BM42 is a bare magnet coil for a Size S2 contactor frame at 220 V DC with spring-loaded terminals. The frame size, voltage, and connector type are all different."},{"question":"What is the control voltage and type for this coil?","answer":"It is a 220 V DC magnet coil. The DC designation means it is designed for a DC control supply, not a rectified AC bus. Verify your control transformer or DC power supply delivers 220 V DC nominal."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1934-5BM42","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/3RT1934-5BM42 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}}