{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1023-3BD40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1023-3BD40","canonicalUrl":"https://aoctrl.com/siemens/3RT1023-3BD40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1023-3BD40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1023-3BD40 power contactor, S0 frame, 10 A AC-12, 4 kW AC-2 at 400 V, screw terminals, 35 mm DIN rail mount.","salesMarkdown":"Rated 10 A in AC-12 duty, this contactor handles resistive and solid-state loads at that current. For motor switching, the AC-2 rating at 400 V is 4 kW, and the AC-4 rating at 400 V is 8.5 A — the AC-4 figure governs reversing and inching applications where the contactor makes and breaks motor current under load. The coil draws 5.4 W closing and 5.4 W holding at DC, so the holding power is the same as the inrush — no power drop after pickup. That simplifies the control transformer sizing: budget a steady 5.4 W per contactor. For standard squirrel-cage motors, the AC-3 rating (not listed here) would normally apply, but the AC-2 and AC-4 ratings give you the real switching capability for the duty cycles that stress the contacts hardest. At 500 V the motor rating is 4.5 kW, and at 690 V it is 5.5 kW — the contactor can handle higher-voltage motors up to those power levels, useful in 690 V distribution systems common in mining or marine installations. Screw-type terminals for the main current circuit accept 2x (0.25 to 2.5 mm²) solid, 2x (1 to 2.5 mm²) stranded, 2x (2.5 to 6 mm²) stranded, and up to 2x 10 mm² or 1x 8 AWG. That covers most panel wiring from control to power feeders. This lets the panel designer choose between protecting the contactor or minimizing upstream fuse size. The S0 frame size is a common Siemens SIRIUS footprint, so panel layouts using this contactor are stable across the product line. If you need a different coil voltage or auxiliary contact configuration, other S0 variants exist within the 3RT1023 family, but the 3RT1023-3BD40 is the specific order code for this 24 V DC coil variant with screw terminals.","metaTitle":"Siemens 3RT1023-3BD40 SIRIUS Power Contactor, S0 Frame, 10 A","metaDescription":"Siemens 3RT1023-3BD40 SIRIUS power contactor, S0 frame, rated 10 A AC-12, 4 kW AC-2 at 400 V. Screw terminals, 35 mm DIN rail mount. Active production.","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":"42 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":"4.5 kW","at 690 V rated value":"5.5 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":"4 kW","at AC-4 at 400 V rated value":"8.5 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=421185&mlfb=3RT1023-3BD40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1023-3BD40/alternatives.json"},"ai":{"faq":[{"question":"What are the key motor ratings for this contactor?","answer":"The AC-2 rating at 400 V is 4 kW, the AC-4 rating at 400 V is 8.5 A, the motor rating at 500 V is 4.5 kW, and at 690 V it is 5.5 kW."},{"question":"What wire sizes does the screw terminal accept?","answer":"The main current circuit terminals accept 2x (0.25 to 2.5 mm²) solid, 2x (1 to 2.5 mm²) stranded, 2x (2.5 to 6 mm²) stranded, and up to 2x 10 mm² or 1x 8 AWG."},{"question":"What fuse coordination is recommended?","answer":"For Type 2 coordination use a 25 A gL/gG fuse; for Type 1 coordination use a 63 A gL/gG fuse."},{"question":"Can this contactor be mounted side-by-side on a DIN rail?","answer":"Yes, side-by-side mounting is permitted with 6 mm spacing at the side, allowing multiple contactors to be ganged without derating."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1023-3BD40","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/3RT1023-3BD40 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}}