{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1045-3AF04","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1045-3AF04","canonicalUrl":"https://aoctrl.com/siemens/3RT1045-3AF04","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1045-3AF04","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT1045-3AF04 power contactor, size S3, AC-2 rated 37 kW at 400 V, AC-4 66 A, screw-type terminals, 70 mm width, 188 mm depth.","salesMarkdown":"For AC-4 duty (plugging, inching, reversing) at 400 V, the rating is 66 A, which governs the contactor's life under high-stress switching. At 500 V the motor power rating is 45 kW; at 690 V it drops to 21.1 kW. These are the numbers that decide whether this contactor survives the duty cycle on your BOM line. ## Termination and Environment Main power circuit uses screw-type terminals accepting 2x (10…50 mm²) stranded or 2x (0.25…2.5 mm²) solid.","metaTitle":"Siemens 3RT1045-3AF04 SIRIUS Power Contactor, 37 kW AC-2","metaDescription":"Siemens 3RT1045-3AF04 SIRIUS power contactor, size S3. AC-2 rated 37 kW at 400 V, AC-4 66 A. Screw terminals, DIN rail mount. Active production. RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"188 mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"70 mm","at AC":"10 ... 25 ms","Height":"146 mm","Stranded":"2x (10 ... 50 mm²)","at 50 Hz":"0.8 ... 1.1","Arcing Time":"10 ... 15 ms","On The Front":"IP20; IP20 on the front with cover / box terminal","1 Rated Value":"50 Hz","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 standard mounting rail","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 50 Hz rated value":"110 V","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","at AWG cables for main contacts":"2x (10 ... 1/0)","For Auxiliary And Control Circuit":"spring-loaded terminals","With Type Of Assignment 2 Required":"fuse gL/gG: 160 A","Surge Voltage Resistance Rated Value":"6 kV","With Type Of Coordination 1 Required":"fuse gL/gG: 250 A","at AWG cables for auxiliary contacts":"2x (24 ... 14)","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 (0.25 ... 1.5 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 (0.25 ... 2.5 mm²)","apparent holding power of magnet coil at AC":"22 VA","apparent pick-up power of magnet coil at AC":"270 VA","Type Of Voltage Of The Control Supply Voltage":"AC","Required Spacing For Grounded Parts At The Side":"6 mm","contact rating of auxiliary contacts according to UL":"A600 / Q600","Inductive Power Factor With Closing Power Of The Coil":"0.68","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Inductive Power Factor With The Holding Power Of The Coil":"0.27","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":"2","number of NO contacts for auxiliary contacts instantaneous contact":"2","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=109128&mlfb=3RT1045-3AF04","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1045-3AF04/alternatives.json"},"ai":{"faq":[{"question":"What are the key power ratings for this contactor?","answer":"AC-2 at 400 V: 37 kW. AC-4 at 400 V: 66 A. Motor power at 500 V: 45 kW; at 690 V: 21.1 kW."},{"question":"What compliance documentation is available?","answer":"RoHS compliance is documented with a substance prohibition date of May 1, 2012. The part is a Siemens SIRIUS product with standard IEC/UL certification applicable to the series."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1045-3AF04","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/3RT1045-3AF04 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}}