{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT5044-1BF40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT5044-1BF40","canonicalUrl":"https://aoctrl.com/siemens/3RT5044-1BF40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT5044-1BF40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, Size S3, 110 V DC coil, screw terminals, 18.6 kW at 690 V, 152 mm depth, 70 mm width, 146 mm height.","salesMarkdown":"## SIRIUS S3 power contactor, 110 V DC coil It carries a 110 V DC coil and is rated for 18.6 kW at 690 V, with an insulation voltage of 1 000 V. The contactor mounts via screw and snap-on onto 35 mm or 75 mm DIN rail, and the mounting position allows ±180° rotation on a vertical surface plus ±22.5° tilt forward or backward — useful when fitting into a crowded enclosure. Rated for motor duty at 400 V and 60 °C, it delivers 59 kW; at 690 V and 60 °C, 102 kW. The AC-3 switching frequency is 1 000 cycles per hour, dropping to 300 cycles per hour for AC-4 duty (plugging/inching). ## Coil and auxiliary circuit The 110 V DC coil draws 15 W closing power and 15 W holding power — a constant-hold design, so the power supply must be sized for that continuous draw. Auxiliary contacts are available (the product extension supports an auxiliary switch), and the auxiliary contact ratings are: 6 A at 24 V, 1 A at 110 V, 0.3 A at 220 V, 6 A at 230 V, and 3 A at 400 V. These cover typical PLC and relay interface signals. Main and auxiliary/control circuits use screw-type terminals. The main circuit accepts 2x (2.5... 16 mm²) solid or stranded, or 2x (10... 1/0) AWG. At 40 °C or 60 °C, the minimum permissible cross-section is 35 mm². The required backup fuse for type 2 coordination is gL/gG 125 A. Side-by-side mounting is permitted, saving rail space in multi-contactor assemblies.","metaTitle":"Siemens 3RT5044-1BF40 SIRIUS Power Contactor, 110 V Coil, S3","metaDescription":"Siemens SIRIUS 3RT5044-1BF40 power contactor, Size S3, 110 V DC coil, rated 18.6 kW at 690 V. Active production. Sourced to order. Get a quote.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"152 mm","Width":"70 mm","at DC":"1 000 1/h","Height":"146 mm","Rated Value":"110 V","During Storage":"-55 ... +80 °C","at AC-1 maximum":"1 000 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","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 690 V rated value":"18.6 kW","Side-By-Side Mounting":"Yes","For Main Current Circuit":"screw-type terminals","Substance Prohibitance (Date)":"03/01/2017","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 400 V at 60 °C rated value":"59 kW","at 690 V at 60 °C rated value":"102 kW","at 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: 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 (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","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":"100 A","at ambient temperature 60 °C rated value":"90 A","Finely Stranded Without Core End Processing":"2x (10 ... 35 mm²)","Type Of Voltage Of The Control Supply Voltage":"DC","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,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/327d03927b5969f98032e6c18224b2ea.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=580023&mlfb=3RT5044-1BF40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT5044-1BF40/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy 3RT5044-1BF40 and get a price?","answer":"This part is sourced to order against an RFQ through independent distribution. Submit a request for current pricing and availability — no stock or price figures are published here."},{"question":"Will 3RT5044-1BF40 fit in a panel designed for 3RT5044-1BM40?","answer":"Yes, same Size S3 frame, same dimensions (152 mm depth, 70 mm width, 146 mm height), same DIN-rail mounting. No rewiring needed for the power circuit. The only difference is the coil: -1BF40 is 110 V DC, -1BM40 is 110 V AC. Ensure the control transformer and coil supply match."},{"question":"What compliance documentation is available for 3RT5044-1BF40?","answer":"RoHS compliance date is 03/01/2017. The evidence does not list UL, CSA, or IEC certifications explicitly, but as a Siemens SIRIUS product it typically carries CE marking for the EU market. Verify specific certification marks with the factory or your local Siemens support."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT5044-1BF40","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/3RT5044-1BF40 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}}