{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2045-1XB40-0LA2","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2045-1XB40-0LA2","canonicalUrl":"https://aoctrl.com/siemens/3RT2045-1XB40-0LA2","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2045-1XB40-0LA2","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RT2045-1XB40-0LA2 power contactor, size S3, DC 24 V coil, screw-type terminals, 77 A at 480 V AC-3, 70 x 140 x 152 mm, DIN-rail mount.","salesMarkdown":"## DC coil performance and control circuit demands The 3RT2045-1XB40-0LA2: The coil is DC 24 V with a 6.5 A inrush peak — the control supply must handle that surge without droop. ## Motor load ratings by voltage In AC-3 duty (squirrel-cage motor switching), the contactor is rated 77 A at 480 V and 62 A at 600 V — enough for a 15 hp motor at 230 V per the listed horsepower figure. These are the operating currents that determine whether the contactor coordinates with upstream overload relays and fuses for Type 2 coordination.","metaTitle":"Siemens 3RT2045-1XB40-0LA2 SIRIUS Contactor, 77 A at 480 V","metaDescription":"Siemens 3RT2045-1XB40-0LA2 SIRIUS power contactor, DC 24 V coil, 77 A at 480 V AC-3. Active production, quoted to order. DIN-rail mount, 70 mm wide.","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","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","Initial Value":"0.7","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Screw-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 DIN 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 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)","Product Brand Name":"SIRIUS","Inrush Current Peak":"6.5 A","Product Designation":"Power 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 440 V rated value":"0.8 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","Duration Of Locked-Rotor Current":"150 ms","Of Auxiliary Circuit Rated Value":"6 kV","For Auxiliary And Control Circuit":"screw-type 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":"Screw-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)","operational current at AC-12 maximum":"10 A","at AC in hot operating state per pole":"5.3 W","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14)","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","Product Function Short Circuit Protection":"No","mirror contact according to IEC 60947-4-1":"Yes","with low demand rate according to SN 31920":"40 %","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,"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=629811&mlfb=3RT2045-1XB40-0LA2","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2045-1XB40-0LA2/alternatives.json"},"ai":{"faq":[{"question":"What is the AC-3 current rating of 3RT2045-1XB40-0LA2 at 480 V?","answer":"77 A at 480 V AC-3, and 62 A at 600 V AC-3. These figures govern motor load sizing and coordination with upstream protection."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2045-1XB40-0LA2","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/3RT2045-1XB40-0LA2 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}}