{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1024-3BF40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1024-3BF40","canonicalUrl":"https://aoctrl.com/siemens/3RT1024-3BF40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1024-3BF40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, Size S0, 3RT1024-3BF40, 110 VDC coil, screw-type terminals, 5.5 kW AC-2 at 400 V, 7.5 kW at 500/690 V, IP20 front, snap-on 35 mm DIN rail.","salesMarkdown":"## SIRIUS Size S0 power contactor, 110 VDC coil The 110 VDC coil draws 5.4 W for both closing and holding, so the control transformer or DC supply needs to sustain that steady-state draw without sag — no inrush spike to worry about on DC, but the continuous 5.4 W means a 24 VA AC supply would be undersized if you're rectifying. Screw-type terminals on the main circuit accept up to 2x 10 mm² or 1x 8 AWG, and the auxiliary side handles 2x (0.25...2.5 mm²) solid. ## Motor ratings and coordination AC-4 at the same voltage is 12.5 A, covering plugging and inching duty for squirrel-cage motors. At 500 V and 690 V the contactor is rated for 7.5 kW, which is the same power at higher line voltages — useful where a 480 V or 690 V distribution is standard. Type 2 coordination requires a 25 A gL/gG fuse; Type 1 allows a 63 A fuse upstream. That selectivity window matters when you're coordinating with a motor protection breaker or downstream short-circuit device. The 45 mm width (one standard modular unit) and 85 mm height fit a compact panel layout. Side-by-side mounting is permitted — no derating gap required between units in the same enclosure, though the IP20 front and IP00 terminal area mean you keep live parts behind a panel door or shrouding.","metaTitle":"Siemens 3RT1024-3BF40 SIRIUS Power Contactor, 110 VDC Coil,","metaDescription":"Siemens 3RT1024-3BF40 SIRIUS power contactor, Size S0, 110 VDC coil, 5.5 kW AC-2 at 400 V, 7.5 kW at 500/690 V. Current lifecycle. Screw & snap-on DIN rail mount. Available to orde","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"100 mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"45 mm","Height":"85 mm","Maximum":"2 000 m","At The Side":"6 mm","Rated Value":"110 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":"7.5 kW","at 690 V rated value":"7.5 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":"5.5 kW","at AC-4 at 400 V rated value":"12.5 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 (0.25 ... 1.5 mm²)","Number of poles for main current circuit":"3","at AWG conductors for auxiliary contacts":"2x (24 ... 14)","Contact reliability of auxiliary contacts":"1 faulty switching per 100 million (17 V, 1 mA)","For Auxiliary And Control Current Circuit":"spring-loaded terminals","at ambient temperature 40 °C rated value":"40 A","Finely Stranded Without Core End Processing":"2x (0.25 ... 2.5 mm²)","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=397824&mlfb=3RT1024-3BF40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1024-3BF40/alternatives.json"},"ai":{"faq":[{"question":"Will 3RT1024-3BF40 drop into a panel specified around 3RT1023-1AL20 without rewiring?","answer":"Yes — same Size S0 frame, same screw-type terminal layout, same 45 mm width and DIN rail mounting. The difference is the coil voltage: 3RT1024-3BF40 uses 110 VDC, while the 3RT1023-1AL20 uses a different coil. Mechanical fit is identical; no rewiring of the power circuit needed."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1024-3BF40","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/3RT1024-3BF40 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}}