{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RT1344-1BB40","brand":"Siemens","brandSlug":"siemens","productSlug":"3RT1344-1BB40","canonicalUrl":"https://aoctrl.com/siemens/3RT1344-1BB40","factsUrl":"https://aoctrl.com/api/mcp/products/3RT1344-1BB40","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS power contactor, 3RT1344-1BB40, S3 frame, 42 kW at 230 V AC-3, screw-type terminals, DIN rail mount.","salesMarkdown":"The Siemens 3RT1344-1BB40 is a SIRIUS power contactor in the S3 frame size, rated for switching motor loads up to 42 kW at 230 V AC-3 duty — that's the rating that governs real motor starts, not the thermal current. Insulation voltage is 1000 V, so it handles 400 V and 690 V line supplies without derating the creepage path. Mounts on 35 mm or 75 mm DIN rail via screw and snap-on fastening — no adapter plate needed. Side-by-side mounting is permitted, which keeps panel width tight when you're stacking multiple contactors on a motor control center bus. The 42 kW at 230 V AC-3 figure is the motor-switching capacity — that's the one that decides whether this contactor handles your pump or conveyor motor. At 400 V AC-3, expect roughly 75 kW (the standard scaling for a 230 V base rating), though the exact number depends on the motor full-load current and the utilization category. The IP20 front protection with cover or box terminal keeps fingers out; the terminal area itself is IP00, so the panel enclosure provides the final ingress barrier. Coil is 24 V DC, drawing 15 W closing power. That's a standard PLC output voltage, but the 15 W inrush means your 24 V DC supply needs enough headroom — a 24 V, 2 A supply can handle about three of these coils closing simultaneously. The 60 °C upper operating limit is useful near furnace lines or in sealed cabinets with minimal ventilation. Main current circuit uses screw-type terminals accepting 2x (10...50 mm²) stranded or 2x (10...1/0) AWG. The 35 mm² minimum permissible cross-section at 40 °C and 60 °C tells you the lug size needed for full rated current. Fuse protection for type 2 coordination requires gL/gG fuses rated 125 A. That's the upstream short-circuit protection that lets the contactor survive a fault without welding its contacts. Substance prohibitance date of 05/01/2012 aligns with RoHS compliance. The contactor carries the usual Siemens CE and UL/CSA markings for IEC and North American installations — confirm the specific UL file number on the nameplate if your site requires it.","metaTitle":"Siemens 3RT1344-1BB40 SIRIUS Power Contactor, 42 kW at 230 V","metaDescription":"Siemens 3RT1344-1BB40 SIRIUS power contactor, S3 frame, 42 kW at 230 V AC-3, 1000 V insulation, screw terminals, DIN rail mount, active production.","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":"24 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=530685&mlfb=3RT1344-1BB40","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RT1344-1BB40/alternatives.json"},"ai":{"faq":[{"question":"What are the key ratings for this contactor?","answer":"Motor switching capacity is 42 kW at 230 V AC-3. Insulation voltage is 1000 V. Coil is 24 V DC, 15 W closing power. Operating temperature range is -25 to +60 °C. Pollution degree 3. Mounts on 35 mm or 75 mm DIN rail."},{"question":"Will 3RT1344-1BB40 drop into a panel specified around 3RT1044-1FB46?","answer":"Not without checking the panel layout. Both are SIRIUS contactors, but the 3RT1344 is an S3 frame size, while the 3RT1044 is a different frame. The mounting rail and terminal spacing may differ. Compare the dimensions — the 3RT1344-1BB40 is 93 mm wide, 146 mm high, 152 mm deep — and verify the terminal lug sizes match your existing wiring."},{"question":"What compliance documentation does this contactor carry?","answer":"RoHS compliance is indicated by the substance prohibitance date of 05/01/2012. As a Siemens SIRIUS product, it typically carries CE, UL, CSA, and IEC certifications — the specific UL file and IEC 60947-4-1 ratings are on the nameplate."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RT1344-1BB40","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/3RT1344-1BB40 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}}