{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1044-3AL20","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1044-3AL20","canonicalUrl":"https://aoctrl.com/siemens/3RT1044-3AL20","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1044-3AL20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, size S3, 3RT1044-3AL20, 37 kW at 500 V / 18.6 kW at 690 V, screw-type terminals, 50/60 Hz coil.","salesMarkdown":"## Siemens SIRIUS 3RT1044-3AL20 — S3 Power Contactor The Siemens 3RT1044-3AL20 is a SIRIUS S3-frame power contactor rated for motor switching up to 37 kW at 500 V and 18.6 kW at 690 V, making it a fit for medium-horsepower induction motors on 400–690 V three-phase lines. The coil accepts 50 or 60 Hz at 230 V, with an operating range factor of 0.8–1.1 at 50 Hz and 0.85–1.1 at 60 Hz — meaning the coil holds in across a sag down to roughly 184 V and overvoltage up to 253 V. Mounting is screw-and-snap-on onto 35 mm or 75 mm standard DIN rail, with side-by-side mounting permitted — no derating gap required between units in a row. The IP20 front enclosure (IP00 at the terminals) suits panel-mount installations where the contactor is behind a cabinet door. Maximum switching rates vary by duty: 1,000 cycles/hour for AC-1 (resistive) and AC-3 (motor start/run), 400 cycles/hour for AC-2 (slip-ring motor), and 300 cycles/hour for AC-4 (plugging/inching). The arcing time spans 10–19 ms at AC, with a tighter 10–15 ms window typical. Main current circuit uses screw-type terminals accepting solid conductors 2x (0.25–2.5 mm²) and stranded 2x (10–50 mm²), plus a mid-range 2x (2.5–16 mm²) for both solid and stranded. The auxiliary contact block is rated for 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V — enough for PLC-level pilot duty or small relay loads.","metaTitle":"Siemens 3RT1044-3AL20 SIRIUS Power Contactor, S3, 37 kW at 5","metaDescription":"Siemens 3RT1044-3AL20 SIRIUS S3 power contactor, 37 kW at 500 V, 18.6 kW at 690 V. Screw terminals, 50/60 Hz coil. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"139 mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"70 mm","at AC":"10 ... 19 ms","Height":"146 mm","Stranded":"2x (10 ... 50 mm²)","at 50 Hz":"0.8 ... 1.1","at 60 Hz":"0.85 ... 1.1","Arcing Time":"10 ... 15 ms","On The Front":"IP20; IP20 on the front with cover / box terminal","1 Rated Value":"50 Hz","2 Rated Value":"60 Hz","During Storage":"-55 ... +80 °C","Of The Terminal":"IP00","at AC-1 maximum":"1 000 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":"230 V","at 500 V rated value":"37 kW","at 60 Hz rated value":"230 V","at 690 V rated value":"18.6 kW","Side-By-Side Mounting":"Yes","at 1000 V rated value":"30 W","For Main Current Circuit":"screw-type terminals","at AC-2 at 400 V rated value":"30 kW","at AC-4 at 400 V rated value":"55 A","Substance Prohibitance (Date)":"05/01/2012","at 40 °C minimum permissible":"35 mm²","at 60 °C minimum permissible":"35 mm²","Insulation Voltage Rated Value":"1 000 V","at 230 V at 60 °C rated value":"34 kW","at 690 V at 60 °C rated value":"102 kW","at 1000 V at 60 °C rated value":"66 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: 125 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":"600 A","Finely Stranded Without Core End Processing":"2x (0.25 ... 2.5 mm²)","apparent holding power of magnet coil at AC":"25 VA","apparent pick-up power of magnet coil at AC":"247 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":"0.62","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":"0","number of NO contacts for auxiliary contacts instantaneous contact":"0","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=320375&mlfb=3RT1044-3AL20","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1044-3AL20/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional alternative to 3RT1044-3AL20?","answer":"The 3RT1044-1FB46 is a peer in the same S3 frame size and power class, but its coil voltage and terminal configuration differ — verify the coil rating before substituting. The 3RT5044-1BM40 and 3RT5045-1AF00 are later-generation SIRIUS variants with different control voltages and accessory compatibility."},{"question":"Where can I buy 3RT1044-3AL20?","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 commitment."},{"question":"What is the depth of 3RT1044-3AL20?","answer":"The depth is 139 mm, with a width of 70 mm and height of 146 mm — fits standard S3 contactor footprint on DIN rail."},{"question":"What compliance documentation is available for 3RT1044-3AL20?","answer":"The SIRIUS series carries CE, UL, CSA, and IEC certifications per Siemens standard practice for industrial control gear. Specific declarations (RoHS, REACH) are available on request with the order."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1044-3AL20","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/3RT1044-3AL20 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}}