{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4074-6BB45","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4074-6BB45","canonicalUrl":"https://aoctrl.com/siemens/3RW4074-6BB45","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4074-6BB45","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4074-6BB45 soft starter, S12 frame, 280 A at 40 °C, 230 V 50/60 Hz, screw fixing, busbar main circuit connection.","salesMarkdown":"## Continuous current and derating — what 280 A really means for the motor The 3RW4074-6BB45: Rated 280 A at 40 °C, this soft starter handles a motor of roughly 160 kW at 230 V — but only if the enclosure ambient stays at or below 40 °C. At 50 °C the continuous rating drops to 248 A; at 60 °C it falls to 215 A. The derating temperature threshold is 40 °C, so any panel with internal temperature rise above that must be factored into the motor full-load current. Pollution degree 3 per IEC 60947-4-2 means the unit tolerates conductive dust and humidity typical of industrial floors — no need for a sealed enclosure unless washdown is present. ## Termination and wiring — main circuit and control Main circuit termination accepts stranded cable 70–240 mm² and finely stranded 50–240 mm², plus busbar connection. For North American wire sizes, the front clamping point takes 3/0–600 kcmil and the back clamping point 250–500 kcmil. Using both clamping points accepts min. 2x 2/0 to max. 2x 500 kcmil. Maximum motor cable length is 300 m — beyond that, capacitive charging current may cause nuisance tripping or reduce the soft starter's ability to limit inrush. Mounting is screw fixing. The S12 frame measures 160 mm wide, 230 mm high, 278 mm deep. Clearances: 100 mm upward, 75 mm downward, 5 mm at the sides. ## Protection and control features Built-in motor overload protection and intrinsic device protection eliminate the need for a separate overload relay in most installations. Adjustable current limitation lets you set the starting current between 20% and 100% of the soft starter's rated current — useful when starting into a limited supply transformer or generator. Minimum load is 20%. External reset input allows remote fault clearing from a PLC or pushbutton station. Thyristor-based with inside-delta circuit not supported. Operating frequency is 50–60 Hz; rated insulation voltage is 600 V.","metaTitle":"Siemens 3RW4074-6BB45 SIRIUS Soft Starter, 280 A, 230 V","metaDescription":"Siemens SIRIUS 3RW4074-6BB45 soft starter, 280 A at 40 °C, 230 V 50/60 Hz, S12 frame. Active production. Quoted to order.","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":"3RW4074-6BB45","Height":"230mm","Upwards":"100mm","Stranded":"70 ... 240 mm²","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter S12 280 A, 200 kW/500 V, 40 °C 400-600 V AC, 230 V AC Screw terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5074-6AB15<<","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":"200kW","at standard circuit at 50 °C rated value":"250hp","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":"400 ... 600V","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":"$3,149.60","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/f0fa9802d3e5c20bf5ae5dd0bbb7bad8.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=39855&mlfb=3RW4074-6BB45"},"ai":{"faq":[{"question":"What is the continuous current rating of 3RW4074-6BB45?","answer":"280 A at 40 °C, derating to 248 A at 50 °C and 215 A at 60 °C. The derating temperature threshold is 40 °C."},{"question":"What are the main circuit wire size options for 3RW4074-6BB45?","answer":"Stranded 70–240 mm², finely stranded 50–240 mm², or busbar connection. North American sizes: front clamp 3/0–600 kcmil, back clamp 250–500 kcmil, both clamps 2x 2/0–2x 500 kcmil."},{"question":"Does 3RW4074-6BB45 include built-in motor overload protection?","answer":"Yes, motor overload protection and intrinsic device protection are integrated, so a separate overload relay is not required for most applications."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4074-6BB45","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/3RW4074-6BB45 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}}