{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1025-1BW40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1025-1BW40","canonicalUrl":"https://aoctrl.com/siemens/3RT1025-1BW40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1025-1BW40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, 3RT1025-1BW40, S0 size, 48 VDC coil, screw-type terminals, 11 kW at 690 V AC.","salesMarkdown":"The 3RT1025-1BW40: Rated coil voltage is 48 VDC. Pick-up voltage is 0.8 x rated value (38.4 V), drop-out is 1.1 x rated value (52.8 V) — so the coil holds in cleanly on a nominal 48 VDC supply and drops out reliably when the supply sags or is switched off. The contactor is size S0, 45 mm wide, 85 mm tall, 101 mm deep, and mounts via screw or snap-on onto 35 mm DIN rail per EN 50022. That means you can pack several S0 contactors on a rail with no extra air gap — useful when panel space is tight. Main contacts are screw-type terminals. Solid wire capacity is 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), max. 2x (0.75...4 mm²); stranded main circuit wire is 2x (1...2.5 mm²), 2x (2.5...6 mm²), max. 2x 10 mm². AWG equivalents: 2x (16...12), 2x (14...10), 1x 8. That covers standard panel wiring up to about 8 AWG — no special crimp tools needed for the main power circuit. ## Duty ratings & coordination AC-3 motor switching at 400 V is rated 7.5 kW; at 690 V it is 11 kW. AC-4 (inching/plugging) at 400 V is 15.5 A. For resistive loads (AC-12) the maximum operating current is 10 A. For DC switching: 24 VDC at 10 A, 60 VDC at 2 A, 110 VDC at 1 A, 220 VDC at 0.3 A. These are the values that determine whether this contactor lives or dies on a given load — match the duty class, not just the voltage. Type 2 coordination requires 25 A. Pollution degree 3 (industrial environment). Coil closing and holding power is 5.4 W DC — a standard 48 VDC power supply can drive several of these without excessive heating. Front face is IP20 (finger-safe), terminal area is IP00 — the wiring compartment is open, so the contactor must be mounted inside an enclosure that provides the overall IP rating. No instantaneous auxiliary contact is included (0 auxiliary contacts as standard) — if you need a feedback signal for a PLC or a status light, order a separate auxiliary contact block that clips onto the S0 frame.","metaTitle":"Siemens 3RT1025-1BW40 SIRIUS Power Contactor, 48 VDC coil, S","metaDescription":"Siemens 3RT1025-1BW40 SIRIUS power contactor, 48 VDC coil, S0 frame, screw terminals, 11 kW at 690 VAC. Current production. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"101 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)","Width":"45 mm","Height":"85 mm","Maximum":"2 000 m","At The Side":"6 mm","Rated Value":"48 V","On The Front":"IP20","Initial Value":"0.8","Mounting type":"screw and snap-on mounting onto 35 mm standard mounting rail according to DIN EN 50022","Of The Terminal":"IP00","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Full-scale value":"1.1","Size of contactor":"S0","Product brand name":"SIRIUS","Degree of pollution":"3","Product designation":"power contactor","at 24 V rated value":"10 A","at 60 V rated value":"2 A","Of Contactor Typical":"10 000 000","at 110 V rated value":"1 A","at 220 V rated value":"0.3 A","at 230 V rated value":"6 A","at 400 V rated value":"3 A","at 500 V rated value":"10 kW","at 690 V rated value":"11 kW","Instantaneous Contact":"0","Side-by-side mounting":"Yes","For Main Current Circuit":"screw-type terminals","Single Or Multi-Stranded":"2x (1 ... 2,5 mm²), 2x (2,5 ... 6 mm²), max. 2x 10 mm²","at AC-2 at 400 V rated value":"7.5 kW","at AC-4 at 400 V rated value":"15.5 A","Closing power of magnet coil at DC":"5.4 W","Holding power of magnet coil at DC":"5.4 W","Operating current at AC-12 maximum":"10 A","With Type Of Assignment 2 Required":"fuse gL/gG: 25 A","at AWG conductors for main contacts":"2x (16 ... 12), 2x (14 ... 10), 1x 8","With Type Of Coordination 1 Required":"fuse gL/gG: 63 A","Reference code acc. to DIN EN 81346-2":"Q","Number of NC contacts for main contacts":"0","Number of NO contacts for main contacts":"3","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Number of poles for main current circuit":"3","at AWG conductors for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","Contact reliability of auxiliary contacts":"1 faulty switching per 100 million (17 V, 1 mA)","For Auxiliary And Control Current Circuit":"screw-type terminals","at ambient temperature 40 °C rated value":"40 A","Type of voltage of the control supply voltage":"DC","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 10 A","Of The Contactor With Added Electronics-Compatible Auxiliary Switch Block Typical":"5 000 000"}},"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=375725&mlfb=3RT1025-1BW40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1025-1BW40/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RT1025-1BW40 and how do I get a price?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time."},{"question":"What is the closest functional second-source for 3RT1025-1BW40?","answer":"The peer 3RT1023-1AL20 is a smaller S0 contactor with a different coil voltage (230 VAC) and lower motor ratings. It will not drop into the same panel without rewiring the coil circuit and checking the load current — the 3RT1025-1BW40 is the correct part for a 48 VDC coil and 11 kW at 690 V."},{"question":"What is 3RT1025-1BW40's listed depth?","answer":"The depth is 101 mm."},{"question":"What wire sizes does the 3RT1025-1BW40 accept on the main terminals?","answer":"Solid wire: 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), max. 2x (0.75...4 mm²). Stranded: 2x (1...2.5 mm²), 2x (2.5...6 mm²), max. 2x 10 mm². AWG: 2x (16...12), 2x (14...10), 1x 8."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1025-1BW40","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/3RT1025-1BW40 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}}