{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1044-3BW40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1044-3BW40","canonicalUrl":"https://aoctrl.com/siemens/3RT1044-3BW40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1044-3BW40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS S3 power contactor, 3RT1044-3BW40, 48 V DC coil, screw-type terminals, snap-on mounting for 35 mm and 75 mm rail, IP20 front.","salesMarkdown":"The Siemens 3RT1044-3BW40 is a SIRIUS S3 power contactor — the core of motor switching and load management in industrial control panels. It's rated for a 48 V DC coil, so it pulls in clean on a standard 48 V DC control bus without a separate power supply tap. It's built for the main current circuit with screw-type terminals, which means you're landing power cables directly — no spring-cage adapters needed. The S3 frame size handles the mechanical and thermal demands of regular switching cycles. IP20 on the front with the cover or box terminal in place; the terminal itself is IP00. That means the front is touch-safe for panel access, but the power lugs need clearance from grounded metal — standard practice for any screw-terminal power device. Dimensions are 146 mm high, 70 mm wide, 152 mm deep — that 152 mm depth is the key number when you're checking gland-plate clearance or enclosure depth. It's a common S3 footprint, so swapping into an existing panel layout should be straightforward if the rail and wireway are already sized for this frame. Main circuit terminals accept solid wire 2x (0.25 to 2.5 mm²) and stranded 2x (10 to 50 mm²) — that's a wide range covering both control-signal pigtails and power conductors. The 2x notation means you can land two conductors per terminal, handy for daisy-chaining or paralleling feeds. Auxiliary or control wiring (solid or stranded) accepts 2x (2.5 to 16 mm²), which covers typical interposing relay and PLC output wiring. RoHS compliance date is 05/01/2012.","metaTitle":"Siemens 3RT1044-3BW40 SIRIUS S3 Power Contactor, 48 V DC","metaDescription":"Siemens 3RT1044-3BW40 SIRIUS S3 power contactor, 48 V DC coil, screw terminals, snap-on 35/75 mm rail mount, IP20 front. Current production. RFQ for sourcing.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"152 mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"70 mm","at DC":"14 ... 20 ms","Height":"146 mm","Stranded":"2x (10 ... 50 mm²)","Arcing Time":"10 ... 15 ms","Rated Value":"48 V","On The Front":"IP20; IP20 on the front with cover / box terminal","Initial Value":"0.8","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","Full-Scale Value":"1.1","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 500 V rated value":"37 kW","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","closing power of magnet coil at DC":"15 W","holding power of magnet coil at DC":"15 W","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)","Type Of Voltage Of The Control Supply Voltage":"DC","Required Spacing For Grounded Parts At The Side":"6 mm","contact rating of auxiliary contacts according to UL":"A600 / Q600","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","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=216590&mlfb=3RT1044-3BW40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1044-3BW40/alternatives.json"},"ai":{"faq":[{"question":"What is the depth of the 3RT1044-3BW40?","answer":"152 mm. That's the dimension from the mounting rail to the front of the contactor, the critical number for enclosure depth clearance."},{"question":"What wire sizes does the main circuit accept?","answer":"Solid wire: 2x (0.25 to 2.5 mm²). Stranded wire: 2x (10 to 50 mm²). Both allow two conductors per terminal."},{"question":"Will the 3RT1044-3BW40 drop into a panel designed for the 3RT1036-1AB00?","answer":"The 3RT1044-3BW40 is an S3 frame size; the 3RT1036-1AB00 is a different frame. Footprint and mounting rail position may not match without panel modifications. Check the dimensional drawings for both before assuming a drop-in swap."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1044-3BW40","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/3RT1044-3BW40 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}}