{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT5045-1AL20","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT5045-1AL20","canonicalUrl":"https://aoctrl.com/siemens/3RT5045-1AL20","factsUrl":"https://aoctrl.com/api/mcp/products/3RT5045-1AL20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS S3 power contactor, 3RT5045-1AL20, 38 kW at 230 V 60 °C, 66 kW at 400 V 60 °C, 114 kW at 690 V 60 °C, screw-type terminals, 70 mm width, 146 mm height, 139 mm depth, DIN rail mount.","salesMarkdown":"The 3RT5045-1AL20 is a SIRIUS S3 frame power contactor, rated for motor switching at 38 kW at 230 V and 66 kW at 400 V when the ambient hits 60 °C — that's the derated ceiling, not the 40 °C catalog number. At 690 V it still delivers 114 kW, so it handles 480 V delta-wye starts without stepping up a frame size. Insulation voltage is rated 1,000 V, and the AC-3e maximum operating voltage goes to 1,000 V — meaning this contactor lives comfortably on 690 V line-to-line systems with margin for switching transients. ## Active production — no lifecycle surprises The substance prohibitance date of 03/01/2017 aligns with RoHS and REACH compliance timelines — the contactor meets the EU substance restrictions that went into force that year. No special handling or disposal paperwork needed for standard industrial waste streams. ## Screw terminals and wire range — what fits At 40 °C the minimum permissible conductor is 50 mm²; at 60 °C it derates to 35 mm² — the terminal itself doesn't limit the ampacity, the temperature rise in the lug does. At AC-3 duty the maximum switching rate is 1,000 cycles per hour; at AC-4 it drops to 300 cycles per hour because the contact wear from inching and plugging accumulates faster.","metaTitle":"Siemens 3RT5045-1AL20 SIRIUS Contactor, S3, 38 kW at 230 V","metaDescription":"Siemens 3RT5045-1AL20 SIRIUS S3 power contactor, 38 kW at 230 V, 66 kW at 400 V. Active production, screw terminals, DIN rail mount. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"139 mm","Width":"70 mm","at AC":"5 000 1/h","title":"3RT5045-1AL20","Height":"146 mm","at 50 Hz":"0.29","at 60 Hz":"0.29","description":"Contactor AC 230 V 50/60 HZ AC3 37 kW 400 V 3-pole, size S3 screw terminal","During Storage":"-55 ... +80 °C","at AC-1 maximum":"900 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 DIN rail","at AC-3e maximum":"1 000 1/h","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 (2.5 ... 16 mm²)","Product Brand Name":"SIRIUS","Degree Of Pollution":"3","Product Designation":"Power contactor","at 24 V rated value":"6 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":"230 V","at 60 Hz rated value":"230 V","at 690 V rated value":"21.1 kW","Side-By-Side Mounting":"Yes","For Main Current Circuit":"screw-type terminals","at AC-3e rated value maximum":"1 000 V","Substance Prohibitance (Date)":"03/01/2017","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 400 V at 60 °C rated value":"66 kW","at 690 V at 60 °C rated value":"114 kW","for AWG cables for main contacts":"2x (10 ... 1/0)","For Auxiliary And Control Circuit":"screw-type terminals","Product Extension Auxiliary Switch":"Yes","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","operational current at AC-12 maximum":"10 A","for AWG cables for auxiliary contacts":"2x (20 ... 16), 2x (18 ... 14), 1x 12","number of NC contacts for main contacts":"0","number of NO contacts for main contacts":"3","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","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","at ambient temperature 40 °C rated value":"120 A","at ambient temperature 60 °C rated value":"100 A","Finely Stranded Without Core End Processing":"2x (10 ... 35 mm²)","Type Of Voltage Of The Control Supply Voltage":"AC","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","number of NC contacts for auxiliary contacts instantaneous contact":"0","number of NO contacts for auxiliary contacts instantaneous contact":"0"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/ce7f66d862b2c1dd6bf04884e34d0545.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=580032&mlfb=3RT5045-1AL20"},"ai":{"faq":[{"question":"Where can I buy 3RT5045-1AL20 and get a price?","answer":"This contactor is sourced to order against your BOM through independent industrial distribution."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT5045-1AL20","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/3RT5045-1AL20 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}