{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4074-6BB44","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4074-6BB44","canonicalUrl":"https://aoctrl.com/siemens/3RW4074-6BB44","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4074-6BB44","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4074-6BB44 soft starter, Size S12, 280 A at 40 °C, 230 V, 50/60 Hz, thyristor-based, screw fixing, busbar connection.","salesMarkdown":"The Siemens 3RW4074-6BB44 is a SIRIUS soft starter, Size S12, designed to ramp up and protect three-phase induction motors. It uses thyristors to control voltage during start, reducing mechanical shock and inrush current. The 230 V rated voltage at 50/60 Hz is the line voltage it's built for. It includes motor overload protection and adjustable current limitation, so you can set the start current profile to match the load. The minimum load is 20%, meaning it needs at least that much motor current to regulate properly — don't use it on a motor that's massively oversized for the load. An external reset input is available for remote fault clearing. Intrinsic device protection covers the soft starter itself against overtemperature and other internal faults. This is a screw-fixing unit, not a DIN-rail snap-on. The dimensions are 230 mm high, 160 mm wide, and 278 mm deep — that's a substantial footprint, so plan your panel layout accordingly. The main current circuit uses busbar connection, with wire ranges for stranded (70 to 240 mm²) and finely stranded (50 to 240 mm²) conductors. For the main contacts in kcmil, it accepts 2/0 to 500 kcmil using both clamping points, with a back clamping point range of 250 to 500 kcmil and a front clamping point range of 3/0 to 600 kcmil. Solid wire for auxiliary contacts is 2x (0.5 to 2.5 mm²). The mounting position is flexible: with an additional fan, it can be mounted on a vertical surface with +/-90° rotation or +/-22.5° tilt; without a fan, the rotation is limited to +/-10°. Clearance requirements: 100 mm upwards, 75 mm downwards, and 5 mm at the side. The maximum wire length to the motor is 300 m — keep that in mind for long cable runs.","metaTitle":"Siemens 3RW4074-6BB44 SIRIUS Soft Starter, 280A at 40°C, Siz","metaDescription":"Siemens SIRIUS 3RW4074-6BB44 soft starter, 280A at 40°C, 230V, Size S12. Active production. Thyristor-based, motor overload protection, adjustable current limit. Order via RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"278mm","Solid":"2x (0.5 ... 2.5 mm²)","Width":"160mm","title":"3RW4074-6BB44","Height":"230mm","Upwards":"100mm","Stranded":"70 ... 240 mm²","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter S12 280 A, 160 kW/400 V, 40 °C 200-460 V AC, 230 V AC Screw terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5074-6AB14<<","During Storage":"-40 ... +80°C","External Reset":"Yes","Finely Stranded":"50 ... 240 mm²","lifecycle_stage":"current","During Operation":"-25 ... +60°C","Fastening Method":"screw fixing","Minimum Load [%]":"20%","For Main Contacts":"2/0 ... 500 kcmil","Mounting Position":"With additional fan: With vertical mounting surface +/-90° rotatable, with vertical mounting surface +/- 22.5° tiltable to the front and back Without additional fan: With vertical mounting surface +/-10° rotatable, with vertical mounting surface +/- 10° t","Product Brand Name":"SIRIUS","Degree Of Pollution":"3, acc. to IEC 60947-4-2","Product Designation":"Soft starter","Wire Length Maximum":"300m","Derating Temperature":"40°C","Inside-Delta Circuit":"No","at 50 Hz rated value":"230V","at 60 Hz rated value":"230V","at 40 °C rated value":"280A","at 50 °C rated value":"248A","at 60 °C rated value":"215A","For Auxiliary Contacts":"2x (20 ... 14)","For Main Current Circuit":"busbar connection","Motor Overload Protection":"Yes","Using Both Clamping Points":"min. 2x 2/0, max. 2x 500 kcmil","Intrinsic Device Protection":"Yes","Adjustable Current Limitation":"Yes","Size Of Engine Control Device":"S12","Using The Back Clamping Point":"250 ... 500 kcmil","Insulation Voltage Rated Value":"600V","Using The Front Clamping Point":"3/0 ... 600 kcmil","Operating Frequency Rated Value":"50 ... 60Hz","Display Version For Fault Signal":"red","Integrated Bypass Contact System":"Yes","For Auxiliary And Control Circuit":"screw-type terminals","Product Component Motor Brake Output":"No","during storage according to IEC 60721":"1K6 (only occasional condensation), 1C2 (no salt mist), 1S2 (sand must not get inside the devices), 1M4","reference code according to EN 61346-2":"Q","during operation according to IEC 60721":"3K6 (no formation of ice, no condensation), 3C3 (no salt mist), 3S2 (sand must not get into the devices), 3M6","during transport according to IEC 60721":"2K2, 2C1, 2S1, 2M2 (max. fall height 0.3 m)","Finely Stranded With Core End Processing":"2x (0.5 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Evaluation Of Thermistor Motor Protection":"No","at standard circuit at 40 °C rated value":"160kW","at standard circuit at 50 °C rated value":"200hp","Finely Stranded Without Core End Processing":"min. 2x 50 mm², max. 2x 185 mm²","number of CO contacts for auxiliary contacts":"1","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"2","Type Of Voltage Of The Control Supply Voltage":"AC","Control Supply Voltage Frequency 1 Rated Value":"50Hz","Control Supply Voltage Frequency 2 Rated Value":"60Hz","Installation Altitude At Height Above Sea Level":"5 000m","continuous operating current [% of Ie] at 40 °C":"115%","Operating Voltage At Standard Circuit Rated Value":"200 ... 460V","contact rating of auxiliary contacts according to UL":"B300 / R300","Relative Negative Tolerance Of The Operating Frequency":"-10%","Relative Positive Tolerance Of The Operating Frequency":"10%","For Auxiliary Contacts Finely Stranded With Core End Processing":"2x (20 ... 16)","Relative Negative Tolerance Of The Control Supply Voltage Frequency":"-10%","Relative Positive Tolerance Of The Control Supply Voltage Frequency":"10%","Relative Negative Tolerance Of The Operating Voltage At Standard Circuit":"-15%","Relative Positive Tolerance Of The Operating Voltage At Standard Circuit":"10%","power loss [W] at operational current at 40 °C during operation typical":"90W","relative negative tolerance of the control supply voltage at AC at 50 Hz":"-15%","relative negative tolerance of the control supply voltage at AC at 60 Hz":"-15%","relative positive tolerance of the control supply voltage at AC at 50 Hz":"10%","relative positive tolerance of the control supply voltage at AC at 60 Hz":"10%","Adjustable Motor Current For Motor Overload Protection Minimum Rated Value":"130A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2,262.00","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/a2838380bba16198583d6bb16520712a.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=398095&mlfb=3RW4074-6BB44"},"ai":{"faq":[{"question":"What are the key current ratings for this soft starter?","answer":"The 3RW4074-6BB44 is rated at 280 A at 40 °C, derating to 248 A at 50 °C and 215 A at 60 °C. The rated voltage is 230 V at 50/60 Hz."},{"question":"What is the physical size and mounting method?","answer":"It is Size S12, with dimensions 230 mm high, 160 mm wide, and 278 mm deep. It uses screw fixing, not DIN-rail mounting. Clearance requirements are 100 mm upwards, 75 mm downwards, and 5 mm at the sides."},{"question":"What wire sizes does it accept for the main circuit?","answer":"For the main current circuit using busbar connection, it accepts stranded wire from 70 to 240 mm² and finely stranded from 50 to 240 mm². In kcmil, it accepts 2/0 to 500 kcmil using both clamping points."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4074-6BB44","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/3RW4074-6BB44 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}