{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1045-1BM40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1045-1BM40","canonicalUrl":"https://aoctrl.com/siemens/3RT1045-1BM40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1045-1BM40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1045-1BM40 power contactor, size S3, screw-type terminals, 37 kW AC-2 at 400 V, 66 A AC-4, 152 mm depth, DIN rail mount.","salesMarkdown":"The AC-4 breaking current of 66 A at 400 V covers reversing and plugging duty, where the contactor must interrupt full motor current. These ratings define the real load it can carry, not just a theoretical maximum. Side-by-side mounting is permitted, which matters when packing multiple contactors into a tight enclosure. The 70 mm width and 146 mm height fit the S3 footprint; depth of 152 mm includes the arc chamber and terminal clearance. Screw-type terminals on the main circuit accept 2x (10…50 mm²) stranded cable; control terminals accept 2x (0.5…1.5 mm²) solid or 2x (0.75…2.5 mm²) stranded. IP20 on the front with cover or box terminal; IP00 at the terminal itself — so the panel enclosure provides the overall IP rating. The AC-4 rating of 66 A at 400 V is the severe-duty figure; if your application involves frequent reversing or inching, that 66 A is the limit, not the AC-2 kW. The coil operates on DC with a pick-up time of 14…20 ms and an arcing time of 10…15 ms. AC-4 drops to 300 per hour due to the higher arc stress.","metaTitle":"Siemens 3RT1045-1BM40 SIRIUS Power Contactor, 37 kW AC-2 at","metaDescription":"Siemens SIRIUS 3RT1045-1BM40 power contactor, size S3, 37 kW AC-2 at 400 V. Active production. Screw terminals, DIN rail mount. Sourced to order via RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"152 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)","Width":"70 mm","at DC":"14 ... 20 ms","Height":"146 mm","Stranded":"2x (10 ... 50 mm²)","Arcing Time":"10 ... 15 ms","Rated Value":"220 V","On The Front":"IP20; IP20 on the front with cover / box terminal","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Of The Terminal":"IP00","at AC-1 maximum":"900 1/h","at AC-2 maximum":"400 1/h","at AC-3 maximum":"1 000 1/h","at AC-4 maximum":"300 1/h","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting onto 35 mm and 75 mm DIN rail","Full-Scale Value":"1.1","Size Of Contactor":"S3","Solid Or Stranded":"2x (2.5 ... 16 mm²)","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":"45 kW","at 690 V rated value":"21.1 kW","Side-By-Side Mounting":"Yes","at 1000 V rated value":"37 W","For Main Current Circuit":"screw-type terminals","at AC-2 at 400 V rated value":"37 kW","at AC-4 at 400 V rated value":"66 A","Substance Prohibitance (Date)":"05/01/2012","at 40 °C minimum permissible":"50 mm²","at 60 °C minimum permissible":"35 mm²","Insulation Voltage Rated Value":"1 000 V","at 230 V at 60 °C rated value":"38 kW","at 690 V at 60 °C rated value":"114 kW","at 1000 V at 60 °C rated value":"82 W","For Auxiliary And Control Circuit":"screw-type terminals","With Type Of Assignment 2 Required":"fuse gL/gG: 160 A","closing power of magnet coil at DC":"15 W","holding power of magnet coil at DC":"15 W","Surge Voltage Resistance Rated Value":"6 kV","With Type Of Coordination 1 Required":"fuse gL/gG: 250 A","operational current at AC-12 maximum":"10 A","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","number of NC contacts for main contacts":"0","number of NO contacts for main contacts":"3","reference code according to IEC 81346-2":"Q","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","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Thermal Short-Time Current Limited To 10 S":"760 A","Finely Stranded Without Core End Processing":"2x (10 ... 35 mm²)","Type Of Voltage Of The Control Supply Voltage":"DC","Required Spacing For Grounded Parts At The Side":"6 mm","contact rating of auxiliary contacts according to UL":"A600 / Q600","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","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","number of NC contacts for auxiliary contacts instantaneous contact":"0","number of NO contacts for auxiliary contacts instantaneous contact":"0","Of The Contactor With Added Electronically Optimized 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=138372&mlfb=3RT1045-1BM40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1045-1BM40/alternatives.json"},"ai":{"faq":[{"question":"What compliance documentation does the 3RT1045-1BM40 carry?","answer":"RoHS compliance is dated to May 1, 2012. The part is a standard SIRIUS catalog item, so CE and UL documentation is available through Siemens channels."},{"question":"What is the depth of the 3RT1045-1BM40?","answer":"The depth is 152 mm, which includes the arc chamber and terminal clearance for screw-type connections."},{"question":"What wire sizes does the 3RT1045-1BM40 accept?","answer":"Main circuit terminals accept 2x (10…50 mm²) stranded. Control terminals accept 2x (0.5…1.5 mm²) solid or 2x (0.75…2.5 mm²) stranded, with a maximum of 2x (0.75…4 mm²) solid."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1045-1BM40","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/3RT1045-1BM40 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}}