{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1045-1XB40-0LA2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1045-1XB40-0LA2","canonicalUrl":"https://aoctrl.com/siemens/3RT1045-1XB40-0LA2","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1045-1XB40-0LA2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, size S3, 24 VDC coil, 45 kW at 500 V, 21.1 kW at 690 V, screw terminals, DIN-rail mount.","salesMarkdown":"## Siemens SIRIUS 3RT1045-1XB40-0LA2 — Power Contactor, Size S3, 24 VDC Coil The Siemens SIRIUS 3RT1045-1XB40-0LA2 is a size S3 power contactor rated for motor switching at 45 kW at 500 V and 21.1 kW at 690 V, with a 24 VDC coil drawing 10 A at rated voltage. It mounts via screw or snap-on onto 35 mm or 75 mm standard DIN rails, fitting into a 70 mm wide, 176 mm tall, 152 mm deep footprint — a compact frame for its power class. Operating temperature spans -40 to +70 °C, with storage down to -55 °C, making it suitable for unconditioned enclosures in industrial environments. ## Switching Performance and Mechanical Life Rated for 1,000 operations per hour in AC-3 duty (motor switching) and 900 ops/h in AC-1 (resistive loads), with a typical mechanical life of 10,000,000 cycles. The arcing time is 10 to 15 ms, and the DC switching capacity at 24 V is 10 A, dropping to 0.3 A at 220 V DC — important for DC auxiliary circuits or brake control. This allows dense panel layouts while maintaining arc-flash and thermal separation.","metaTitle":"Siemens 3RT1045-1XB40-0LA2 SIRIUS Power Contactor, 24 VDC, 4","metaDescription":"Siemens SIRIUS 3RT1045-1XB40-0LA2 power contactor, size S3, 24 VDC coil, 45 kW at 500 V, 21.1 kW at 690 V. Screw terminals, DIN-rail mount. Current lifecycle stage, available to or","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":"176 mm","Upwards":"10 mm","Forwards":"20 mm","Stranded":"2x (10 ... 50 mm²)","Downwards":"10 mm","Arcing Time":"10 ... 15 ms","At The Side":"10 mm","Rated Value":"24 V","Initial Value":"0.7","During Storage":"-55 ... +80 °C","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":"-40 ... +70 °C","Fastening Method":"screw and snap-on mounting onto 35 mm and 75 mm standard mounting rail","Full-Scale Value":"1.25","Size Of Contactor":"S3","Solid Or Stranded":"2x (2.5 ... 16 mm²)","Product Brand Name":"SIRIUS","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","Instantaneous Contact":"0","Side-By-Side Mounting":"Yes","at 1000 V rated value":"37 W","For Main Current Circuit":"screw-type terminals","at maximum AC-1 rated value":"50 mm²","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","Design Of The Surge Suppressor":"with varistor","at AWG cables for main contacts":"2x (10 ... 1/0)","For Auxiliary And Control Circuit":"screw-type terminals","Function Module For Communication":"No","With Type Of Assignment 2 Required":"fuse gL/gG: 160 A","closing power of magnet coil at DC":"19 W","holding power of magnet coil at DC":"12 W","With Type Of Coordination 1 Required":"fuse gL/gG: 250 A","at AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","operational current at AC-12 maximum":"10 A","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","Finely Stranded Without Core End Processing":"2x (10 ... 35 mm²)","Type Of Voltage Of The Control Supply Voltage":"DC","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","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=231644&mlfb=3RT1045-1XB40-0LA2","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1045-1XB40-0LA2/alternatives.json"},"ai":{"faq":[{"question":"How do I get current pricing and availability for 3RT1045-1XB40-0LA2?","answer":"Submit an RFQ through this listing. The part is sourced to order through independent distribution; pricing and stock levels are confirmed at quote time."},{"question":"What is the closest functional second-source to 3RT1045-1XB40-0LA2?","answer":"The 3RT1044-1FB46 is a size S2 contactor with a different frame and lower power rating; it will not drop into the same panel without rewiring and resizing. The 3RT5045-1AC20 and 3RT5045-1AF00 are higher-performance SIRIUS 3RT5 series contactors with different coil voltages and terminal arrangements — not direct form-fit replacements."},{"question":"What compliance documentation does Siemens provide for 3RT1045-1XB40-0LA2?","answer":"Siemens provides RoHS, REACH, and IEC/EN 60947-4-1 compliance documentation as standard for the SIRIUS contactor range. UL and CSA certifications are also typically available; confirm specific certificate numbers at order time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1045-1XB40-0LA2","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/3RT1045-1XB40-0LA2 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}}