{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1044-1AH20","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1044-1AH20","canonicalUrl":"https://aoctrl.com/siemens/3RT1044-1AH20","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1044-1AH20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, 3RT1044-1AH20, S3 frame, 48 VAC 50/60 Hz coil, screw-type terminals, 37 kW at 500 V AC-3.","salesMarkdown":"It is a current-production part. The S3 frame (146 mm high, 70 mm wide, 139 mm deep) occupies a standard DIN-rail footprint with room for auxiliary contact blocks on the front. Rated for AC-3 motor switching at 37 kW at 500 V and 18.6 kW at 690 V — these are the numbers that govern motor starting and running duty. For a 37 kW motor at 500 V, this contactor handles the inrush and breaking current without excessive contact wear. At 690 V the power drops to 18.6 kW because the same current limit applies at higher voltage. The main current circuit uses screw-type terminals, accepting solid conductors 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), max. 2x (0.75...4 mm²), and stranded conductors 2x (10...50 mm²). The larger stranded range (up to 50 mm²) handles the motor feeder; the smaller solid range suits control wiring for auxiliary contacts. Auxiliary contact ratings: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V — these are the make/break capacities for the built-in auxiliary contacts. Use them for PLC inputs, contactor feedback, or interlocking. Maximum switching rates: 1,000 1/h at AC-1 and AC-3, 400 1/h at AC-2, 300 1/h at AC-4. IP20 on the front with cover or box terminal; IP00 at the terminal itself. The front IP20 is adequate for finger-safe installation inside a locked panel; the open terminal area requires the panel door to be closed during operation. Operating temperature -25...+60 °C, storage -55...+80 °C. Switching times: arcing time 10...15 ms, total make/break time at AC 10...19 ms. These are fast enough for most motor control sequences; for synchronised switching or soft-starter bypass, the 10 ms spread matters for timing coordination. The 48 VAC coil variant is less common than the 24 VDC or 230 VAC versions, so lead time may be slightly longer than the popular coil codes. Plan the RFQ with that in mind if the panel was originally specified around this exact voltage.","metaTitle":"Siemens 3RT1044-1AH20 SIRIUS Power Contactor, 48 VAC Coil, S","metaDescription":"Siemens SIRIUS 3RT1044-1AH20 power contactor, 48 VAC 50/60 Hz coil, S3 size, 37 kW at 500 V. Screw terminals, DIN rail mount. Active production. RFQ for BOM line.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"139 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 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":"48 V","at 500 V rated value":"37 kW","at 60 Hz rated value":"48 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":"screw-type 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 (20 ... 16), 2x (18 ... 14), 1x 12","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 (0.5 ... 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)","Thermal Short-Time Current Limited To 10 S":"600 A","Finely Stranded Without Core End Processing":"2x (10 ... 35 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=74174&mlfb=3RT1044-1AH20","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1044-1AH20/alternatives.json"},"ai":{"faq":[{"question":"What is the depth of the 3RT1044-1AH20?","answer":"The depth is 139 mm. This is the dimension from the mounting rail to the furthest projection of the contactor body, not including any auxiliary contact blocks mounted on the front."},{"question":"What wire sizes does the 3RT1044-1AH20 accept on the main terminals?","answer":"Solid conductors: 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), max. 2x (0.75...4 mm²). Stranded conductors: 2x (10...50 mm²). The main circuit uses screw-type terminals."},{"question":"Will 3RT1044-1AH20 drop into a panel specified around 3RT1044-1FB46?","answer":"Yes, both are S3 frame size with the same mounting footprint (screw and snap-on onto 35 mm or 75 mm rail) and the same dimensions (146 mm high, 70 mm wide, 139 mm deep). The only difference is the coil voltage — verify that the 48 VAC coil matches your control circuit before swapping."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1044-1AH20","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/3RT1044-1AH20 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}}