{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT2045-3AH00","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT2045-3AH00","canonicalUrl":"https://aoctrl.com/siemens/3RT2045-3AH00","factsUrl":"https://aoctrl.com/api/mcp/products/3RT2045-3AH00","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS S3 power contactor, 3RT2045-3AH00, 77 A at 480 V AC-3, spring-type coil terminals, screw and snap-on 35 mm DIN rail mount.","salesMarkdown":"## SIRIUS S3 power contactor — 77 A AC-3 at 480 V The Siemens 3RT2045-3AH00 is a SIRIUS S3 power contactor rated for 77 A in AC-3 duty at 480 V, which means it handles motor switching loads up to that current — common for 40–50 hp induction motors on 480 V three-phase lines. Mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, with ±180° rotation on a vertical surface and ±22.5° tilt forward/backward — useful when the panel layout forces an odd orientation. The S3 frame (Size 3) is the physical envelope; at 70 mm wide, 140 mm tall, and 152 mm deep, it occupies a standard DIN-rail footprint with clearance requirements of 10 mm upwards, 10 mm downwards, 20 mm forwards, and 10 mm at the side. Main power terminals accept solid conductors from 2.5 to 16 mm² or stranded from 6 to 70 mm² — the stranded range covers the heavier cable gauges typical for a 77 A motor circuit. Auxiliary and coil terminals use spring-type connections accepting 2x (0.5 to 2.5 mm²) solid or stranded, which speeds panel wiring compared to screw terminals on the control side. Coil arcing time runs 10–20 ms; switching frequency varies by duty class — up to 1 000 cycles/hour in AC-3, 900 in AC-1, 400 in AC-2, and 300 in AC-4. Mechanical life is typical at 10 million operations. Coil draws 10 A at 24 V rated value; auxiliary contact ratings span 2 A at 48/60 V down to 0.3 A at 220 V and 0.8 A at 440 V — check the specific control voltage against your PLC output card's sink capacity.","metaTitle":"Siemens 3RT2045-3AH00 SIRIUS S3 Power Contactor, 77 A at 480","metaDescription":"Siemens SIRIUS S3 power contactor 3RT2045-3AH00, rated 77 A AC-3 at 480 V. Spring-type coil terminals, screw and snap-on DIN rail mount. Current lifecycle stage, available to order","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Contactors"],"specifications":{"Depth":"152 mm","Solid":"2.5 ... 16 mm²","Width":"70 mm","at AC":"10 ... 21 ms","Height":"140 mm","Upwards":"10 mm","Forwards":"20 mm","Stranded":"6 ... 70 mm²","at 50 Hz":"0.38","Downwards":"10 mm","Arcing Time":"10 ... 20 ms","At The Side":"10 mm","During Storage":"-55 ... +80 °C","Of Magnet Coil":"Spring-type terminals","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","Auxiliary Switch":"Yes","During Operation":"-25 ... +60 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715","at AC-3e maximum":"1 000 1/h","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","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 50 Hz rated value":"48 V","at 500 V rated value":"2 A","at 600 V rated value":"62 A","at 690 V rated value":"1 A","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","Relative Humidity Minimum":"10 %","Of Main Circuit Rated Value":"8 kV","Safety-Related Switching On":"Yes","at AC-3 rated value maximum":"1 000 V","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","safety-related switching OFF":"Yes","Substance Prohibitance (Date)":"03/01/2017","Of Auxiliary Circuit Rated Value":"6 kV","at AC-5a up to 690 V rated value":"110 A","at AC-5b up to 400 V rated value":"80 A","For Auxiliary And Control Circuit":"spring-loaded terminals","Function Module For 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":"19 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)","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)","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","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","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 %","Type Of Voltage Of The Control Supply Voltage":"AC","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)","minimum cross-section in main circuit at maximum AC-1 rated value":"50 mm²","number of NC contacts for auxiliary contacts instantaneous contact":"1","number of NO contacts for auxiliary contacts instantaneous contact":"1","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=629820&mlfb=3RT2045-3AH00","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT2045-3AH00/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source for 3RT2045-3AH00?","answer":"The closest functional peer is the 3RT5045-1AF00, which shares the SIRIUS S3 frame and similar AC-3 current rating. The 3RT2015-2AP02 is a smaller S0 frame contactor and would not drop into the same panel without rewiring — different footprint and terminal capacity."},{"question":"What compliance documentation does Siemens provide for 3RT2045-3AH00?","answer":"As a SIRIUS series component, it carries CE marking for the European market and is designed to meet IEC 60947-4-1 for contactors and motor starters. UL and CSA listings are typical for this series, though specific certification numbers should be verified against the nameplate for the exact variant."},{"question":"Where can I buy 3RT2045-3AH00 and what is the lead time?","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 lead time and price."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT2045-3AH00","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/3RT2045-3AH00 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}}