{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1344-1BM40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1344-1BM40","canonicalUrl":"https://aoctrl.com/siemens/3RT1344-1BM40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1344-1BM40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, Size S3, 3RT1344-1BM40, 42 kW at 230 V 60 °C, screw-type terminals, DIN-rail mount.","salesMarkdown":"## SIRIUS Size S3 power contactor — 3RT1344-1BM40 The Siemens 3RT1344-1BM40 is a SIRIUS power contactor in the Size S3 frame, rated for motor switching up to 42 kW at 230 V at 60 °C. That 42 kW figure is the AC-3 duty rating at 60 °C ambient — the real-world motor load it can handle continuously in a warm panel. Insulation voltage is rated 1 000 V, so it's comfortable in 400 V and 690 V systems with headroom. Main circuit terminals are screw-type, accepting stranded cable up to 2x (10... 50 mm²) or solid up to 2x (0.5... 1.5 mm²) with smaller gauges. Auxiliary and control circuits also use screw terminals. The contactor occupies 93 mm width, 146 mm height, 152 mm depth — that depth is the body plus terminals; factor it into gland-plate clearance. ## Coil and switching performance Closing power of the magnet coil at DC is 15 W. Arcing time runs 10... 15 ms, and at DC the contactor operates in 14... 20 ms. Mechanical life is typical 10 000 000 operations. At AC-1 (resistive load) it can cycle up to 1 000 1/h. For short-circuit protection with type 2 coordination, the required fuse is gL/gG 125 A.","metaTitle":"Siemens 3RT1344-1BM40 SIRIUS Power Contactor, Size S3, 42 kW","metaDescription":"Siemens SIRIUS 3RT1344-1BM40 power contactor, Size S3, 42 kW at 230 V 60 °C. Screw terminals, DIN-rail mount. Current production. Quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Contactors"],"specifications":{"Depth":"152 mm","Solid":"2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), max. 2x (0.75 ... 4 mm²)","Width":"93 mm","at DC":"14 ... 20 ms","Height":"146 mm","Stranded":"2x (10 ... 50 mm²)","Arcing Time":"10 ... 15 ms","Rated Value":"220 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","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","Side-By-Side Mounting":"Yes","For Main Current Circuit":"screw-type terminals","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":"42 kW","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","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":"4","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":"4","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)","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=523413&mlfb=3RT1344-1BM40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1344-1BM40/alternatives.json"},"ai":{"faq":[{"question":"Will 3RT1344-1BM40 drop into a panel that was specified around 3RT1044-1FB46 without rewiring?","answer":"The 3RT1344-1BM40 is a Size S3 frame with screw terminals; the 3RT1044-1FB46 is a different frame variant. Both are SIRIUS power contactors, but the physical footprint and terminal layout differ — a direct mechanical swap without checking the mounting hole pattern and wiring is not guaranteed. Verify the panel cutout and terminal assignments before ordering."},{"question":"What is 3RT1344-1BM40's listed depth (152 mm) on this component line?","answer":"The depth is 152 mm, measured from the mounting surface to the furthest terminal projection."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1344-1BM40","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/3RT1344-1BM40 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}}