{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1024-3KB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1024-3KB40","canonicalUrl":"https://aoctrl.com/siemens/3RT1024-3KB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1024-3KB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1024-3KB40 power contactor, S0 size, 24 VDC coil, screw terminals, IP20 front, 45 mm width.","salesMarkdown":"Its 24 VDC coil draws 4.2 W during both closing and holding, so the control transformer or DC supply must be sized for that steady-state draw — no inrush spike to worry about on DC. The varistor surge suppressor is built in, meaning no external snubber needed for coil suppression. The AC-3 motor-switching rating at 400 V is not directly stated, but the AC-2 rating at 400 V is 5.5 kW and the AC-4 rating at 400 V is 12.5 A. For a typical three-phase induction motor, the AC-3 rating would be higher than AC-2 — expect this contactor to handle a 5.5 kW motor in standard starting duty. For resistive or general-purpose loads (AC-12), the maximum operating current is 10 A. The auxiliary contact ratings span from 10 A at 24 V down to 0.3 A at 220 V and 3 A at 400 V — useful for pilot-duty circuits. Dimensions are 45 mm wide, 88 mm high, and 100 mm deep — the S0 frame fits standard 45 mm DIN-rail spacing. Main circuit terminals accept screw-type connections: 2x (0.25 to 2.5 mm²) solid, 2x (1 to 2.5 mm²) stranded, up to 2x 10 mm² max. AWG equivalents are 2x (16 to 12) solid, 2x (14 to 10) stranded, or 1x 8. For type 2 coordination, use a gL/gG fuse rated 25 A; for type 1, 63 A. Pollution degree 3.","metaTitle":"Siemens 3RT1024-3KB40 SIRIUS Power Contactor, 24 VDC Coil, S","metaDescription":"Siemens SIRIUS 3RT1024-3KB40 power contactor, 24 VDC coil, S0 frame, 10 A at 24 V, screw terminals, IP20 front. Active production. Sourced to order against RFQ.","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":"88 mm","Maximum":"2 000 m","At The Side":"6 mm","Rated Value":"24 V","On The Front":"IP20","Initial Value":"0.7","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":"1.25","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","Design of the surge suppressor":"with varistor","Closing power of magnet coil at DC":"4.2 W","Holding power of magnet coil at DC":"4.2 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","For Short-Circuit Protection Of The Auxiliary Switch Required":"fuse gL/gG: 10 A"}},"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=59586&mlfb=3RT1024-3KB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1024-3KB40/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source to 3RT1024-3KB40?","answer":"The 3RT1023-1AL20 is a smaller-frame sibling (S00 vs S0) with a different coil voltage and terminal style — it will not drop into the same panel without rewiring and a different DIN-rail footprint. For a direct S0-frame replacement with the same 24 VDC coil, stick with the 3RT1024-3KB40."},{"question":"What is the depth of 3RT1024-3KB40?","answer":"The depth is 100 mm, with a width of 45 mm and height of 88 mm."},{"question":"What wire sizes does the 3RT1024-3KB40 accept?","answer":"Main circuit screw terminals accept 2x (0.25 to 2.5 mm²) solid, 2x (1 to 2.5 mm²) stranded, up to 2x 10 mm² max. AWG equivalents: 2x (16 to 12) solid, 2x (14 to 10) stranded, or 1x 8."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1024-3KB40","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/3RT1024-3KB40 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}}