{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2045-3XB40-0LA2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2045-3XB40-0LA2","canonicalUrl":"https://aoctrl.com/siemens/3RT2045-3XB40-0LA2","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2045-3XB40-0LA2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS contactor, 24 VDC coil, Size S3, spring-type terminals, 3RT2045-3XB40-0LA2.","salesMarkdown":"## What you're looking at It's designed for switching motor loads — think pumps, conveyors, compressors — in industrial control panels. The coil pulls 6.5 A inrush peak and holds at 24 VDC nominal. Pick-up is at 0.7 of rated voltage; drop-out is at 1.25 of rated voltage, so it releases reliably on undervoltage. ## Ratings that matter for the line For motor duty, the AC-3 rating is what drives selection: 77 A at 480 V and 62 A at 600 V. That translates to 15 hp at 230 V — enough for a moderate pump or a small conveyor drive. The main contacts are rated for AC-4 duty at 300 operations per hour maximum — that's the severe switching category for plugging or inching. If your application does frequent reversing, this is the number to watch. The arcing time runs 10 to 20 ms, and the operating time (DC) is 38 to 57 ms. That's fast enough for most sequence control. The Size S3 footprint is 70 mm wide, 140 mm high, and 152 mm deep — so it takes up about the space of a thick paperback on the rail. That helps when you're squeezing it into a crowded enclosure. Keep those gaps for airflow and arc flash separation. ## Terminals and wiring The magnet coil uses spring-type terminals — no screwdriver needed for the coil connection. Main contact wiring accepts 2x (0.5 to 2.5 mm²) solid or stranded, which covers standard control wiring up to 14 AWG. ## Environmental range Operating temperature spans -40 to +70 °C — fine for unheated plant floors or outdoor cabinets in moderate climates.","metaTitle":"Siemens 3RT2045-3XB40-0LA2 SIRIUS Contactor, 24 VDC, Size S3","metaDescription":"Siemens SIRIUS contactor 3RT2045-3XB40-0LA2, 24 VDC coil, Size S3, spring-type terminals, rated for motor loads up to 77 A at 480 V. Currently in production. Quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"152 mm","Width":"70 mm","at DC":"38 ... 57 ms","title":"3RT2045-3XB40-0LA2","Height":"140 mm","Upwards":"10 mm","Forwards":"20 mm","Downwards":"10 mm","Arcing Time":"10 ... 20 ms","At The Side":"10 mm","Rated Value":"24 V","description":"traction contactor, AC-3e/AC-3, 80 A, 37 kW / 400 V, 3-pole, 24 V DC, 0.7-1.25* Us, electronic drive, with integrated varistor, auxiliary contacts: 1 NO + 1 NC, main circuit: screw terminal, control and auxiliary circuit: spring-loaded terminal, size: S3","Initial Value":"0.7","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Spring-type terminals","Type Of Voltage":"DC","at AC-4 maximum":"300 1/h","lifecycle_stage":"current","Auxiliary Switch":"Yes","During Operation":"-40 ... +70 °C","Fastening Method":"screw and snap-on mounting onto 35 mm standard mounting rail according to DIN EN 60715","Full-Scale Value":"1.25","For Main Contacts":"10 ... 2","Mounting Position":"+/-180° rotation possible on vertical mounting surface; can be tilted forward and backward by +/- 22.5° on vertical mounting surface","Size Of Contactor":"S3","Solid Or Stranded":"2x (0.5 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Inrush Current Peak":"6.5 A","Product Designation":"Contactor","at 24 V rated value":"10 A","at 48 V rated value":"2 A","at 60 V rated value":"2 A","Of Contactor Typical":"10 000 000","at 110 V rated value":"1 A","at 125 V rated value":"0.9 A","at 220 V rated value":"0.3 A","at 230 V rated value":"15 hp","at 400 V rated value":"3 A","at 480 V rated value":"77 A","at 500 V rated value":"2 A","at 600 V rated value":"62 A","at 690 V rated value":"1 A","Design Of The Product":"With extended operating range","Instantaneous Contact":"1","Side-By-Side Mounting":"Yes","at 1000 V rated value":"37 kW","For Auxiliary Contacts":"20 ... 14","For Main Current Circuit":"screw-type terminals","at 110/120 V rated value":"7.5 hp","at 200/208 V rated value":"25 hp","at 220/230 V rated value":"30 hp","at 460/480 V rated value":"60 hp","at 575/600 V rated value":"60 hp","at AC-2 at AC-3e maximum":"400 1/h","Locked-Rotor Current Peak":"6.5 A","Relative Humidity Minimum":"10 %","Holding Current Mean Value":"75 mA","at maximum Ith rated value":"50 mm²","Of Main Circuit Rated Value":"8 kV","at AC-3 rated value maximum":"1 000 V","at maximum AC-1 rated value":"50 mm²","at AC in hot operating state":"15.9 W","at AC-2 at 400 V rated value":"37 kW","at AC-3e rated value maximum":"1 000 V","at AC-4 at 400 V rated value":"66 A","Substance Prohibitance (Date)":"03/01/2017","Design Of The Surge Suppressor":"with varistor","Duration Of Inrush Current Peak":"50 µs","Locked-Rotor Current Mean Value":"3.2 A","at AWG cables for main contacts":"2x (10 ... 1/0), 1x (10 ... 2)","Duration Of Locked-Rotor Current":"150 ms","Of Auxiliary Circuit Rated Value":"6 kV","For Auxiliary And Control Circuit":"spring-loaded terminals","Function Module For Communication":"No","Product Function Bus Communication":"No","With Type Of Assignment 2 Required":"gG: 160A (690V,100kA), aM: 80A (690V,100kA), BS88: 125A (415V,80kA)","Without Load Current Share Typical":"1.8 W","closing power of magnet coil at DC":"76 W","holding power of magnet coil at DC":"1.8 W","At Contactor For Auxiliary Contacts":"Spring-type terminals","With Type Of Coordination 1 Required":"gG: 250 A (690 V, 100 kA), aM: 160 A (690 V, 100 kA), BS88: 200 A (415 V, 80 kA)","at AWG cables for auxiliary contacts":"2x (20 ... 16)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"5.3 W","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)","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"No","mirror contact according to IEC 60947-4-1":"Yes","with low demand rate according to SN 31920":"40 %","Finely Stranded Without Core End Processing":"2x (0.5 ... 2.5 mm²)","with high demand rate according to SN 31920":"73 %","number of NC contacts for auxiliary contacts":"1","number of NO contacts for auxiliary contacts":"1","Type Of Voltage Of The Control Supply Voltage":"DC","up to 40 °C according to IEC 60077 rated value":"125 A","up to 70 °C according to IEC 60077 rated value":"90 A","Limited To 1 S Switching At Zero Current Maximum":"1 500 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 5 S Switching At Zero Current Maximum":"1 186 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 10 S Switching At Zero Current Maximum":"851 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 30 S Switching At Zero Current Maximum":"538 A; Use minimum cross-section acc. to AC-1 rated value","Limited To 60 S Switching At Zero Current Maximum":"423 A; Use minimum cross-section acc. to AC-1 rated value","contact rating of auxiliary contacts according to UL":"A600 / P600","Of Main Circuit With Degree Of Pollution 3 Rated Value":"1 000 V","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Of The Contactor With Added Auxiliary Switch Block Typical":"10 000 000","Of Auxiliary Circuit With Degree Of Pollution 3 Rated Value":"690 V","For Short-Circuit Protection Of The Auxiliary Switch Required":"gG: 10 A (500 V, 1 kA)","Of The Contactor With Added Electronically Optimized Auxiliary Switch Block Typical":"5 000 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/7d28fa7380658c541019ac8751bc4da6.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=629836&mlfb=3RT2045-3XB40-0LA2"},"ai":{"faq":[{"question":"What is the coil voltage and type for this contactor?","answer":"The coil is 24 VDC, with an inrush peak of 6.5 A. Pick-up occurs at 0.7 of rated voltage, and drop-out at 1.25 of rated voltage."},{"question":"What motor ratings does this contactor support?","answer":"It handles 77 A at 480 V and 62 A at 600 V for AC-3 motor duty, and 15 hp at 230 V. The AC-4 switching rate is limited to 300 operations per hour."},{"question":"Where can I buy 3RT2045-3XB40-0LA2 and how is it quoted?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2045-3XB40-0LA2","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/3RT2045-3XB40-0LA2 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}