{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4426-3BC45","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4426-3BC45","canonicalUrl":"https://aoctrl.com/siemens/3RW4426-3BC45","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4426-3BC45","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4426-3BC45 soft starter, 133 A at 40 °C, 690 V insulation voltage, 50/60 Hz, integrated bypass, screw fixing, box terminal main circuit.","salesMarkdown":"## Current derating and bypass — what drives the real rating The 3RW4426-3BC45: Rated 133 A at 40 °C, derated to 118 A at 50 °C and 102 A at 60 °C — the ambient inside the panel sets the usable current, not the nameplate number. Integrated bypass contact system means the thyristors are shorted out once the motor is up to speed, cutting heat dissipation in the enclosure and letting the soft starter run cooler in continuous duty. ## Mounting, clearances, and terminal wiring Dimensions 170 mm wide × 192 mm high × 270 mm deep; screw fixing to the back panel, not DIN rail. Mounting position allows ±90° rotation and ±22.5° tilt front-to-back. Minimum clearance: 100 mm above, 75 mm below, 5 mm at the sides — plan the gland plate and busbar routing to keep airflow open. Main circuit uses box terminals accepting 2× (4 … 50 mm²) stranded or 2× (10 … 1/0 AWG). ## Protection, control, and inside-delta wiring Built-in motor overload protection and intrinsic device protection reduce the need for separate relays in the starter bucket. Adjustable current limitation lets you set the starting torque profile per load. Inside-delta circuit capability — for six-lead motors, the soft starter can be wired inside the delta to run at a lower current rating per phase, saving panel space and cost. Minimum load is 8 % — light-load applications like small pumps or fans need to stay above this threshold to avoid misfiring the thyristors. External reset input and a fault display simplify remote troubleshooting without opening the panel door. ## Insulation, environment, and wire length Rated insulation voltage 690 V with pollution degree 3 per IEC 60947-4-2 — suitable for industrial environments with conductive dust or condensation. Operating temperature range –25 to +60 °C during operation, storage from –25 to +80 °C. Maximum motor cable length 500 m — stay under this to avoid reflected-wave trips on long runs.","metaTitle":"Siemens 3RW4426-3BC45 SIRIUS Soft Starter, 133 A, 690 V","metaDescription":"Siemens 3RW4426-3BC45 SIRIUS soft starter, 133 A at 40 °C, 690 V insulation, integrated bypass, in active production. Quoted to order via RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"270mm","Solid":"2x (0.25 ... 1.5 mm²)","Width":"170mm","title":"3RW4426-3BC45","Height":"192mm","Upwards":"100mm","Stranded":"2x (4 ... 50 mm²)","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter Values at 500 V, 40 °C standard: 77 A, 45 kW Inside-delta: 133 A, 90 kW 400-600 V AC, 230 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5526-3HA16<<","During Storage":"-25 ... +80°C","External Reset":"Yes","lifecycle_stage":"current","During Operation":"60°C","Fastening Method":"screw fixing","Minimum Load [%]":"8%","Mounting Position":"with vertical mounting surface +/-90° rotatable, with vertical mounting surface +/- 22.5° tiltable to the front and back","Product Brand Name":"SIRIUS","Degree Of Pollution":"3, acc. to IEC 60947-4-2","Product Designation":"Soft starter","Wire Length Maximum":"500m","Derating Temperature":"40°C","Inside-Delta Circuit":"Yes","at 50 Hz rated value":"230V","at 60 Hz rated value":"230V","at 40 °C rated value":"133A","at 50 °C rated value":"118A","at 60 °C rated value":"102A","For Auxiliary Contacts":"2x (24 ... 16)","For Main Current Circuit":"box terminal","Motor Overload Protection":"Yes","Using Both Clamping Points":"2x (10 ... 1/0)","Intrinsic Device Protection":"Yes","Adjustable Current Limitation":"Yes","Using The Back Clamping Point":"10 ... 2/0","Insulation Voltage Rated Value":"690V","Using The Front Clamping Point":"10 ... 2/0","Operating Frequency Rated Value":"50 ... 60Hz","Display Version For Fault Signal":"Display","Integrated Bypass Contact System":"Yes","For Auxiliary And Control Circuit":"spring-loaded terminals","Product Component Motor Brake Output":"Yes","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 (0.25 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Evaluation Of Thermistor Motor Protection":"Yes","at standard circuit at 40 °C rated value":"45kW","at standard circuit at 50 °C rated value":"50hp","Finely Stranded Without Core End Processing":"2x (4 ... 35 mm²)","number of CO contacts for auxiliary contacts":"1","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"3","Type Of Voltage Of The Control Supply Voltage":"AC","at inside-delta circuit at 40 °C rated value":"90kW","at inside-delta circuit at 50 °C rated value":"100hp","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","Operating Voltage At Inside-Delta Circuit Rated Value":"400 ... 600V","Relative Negative Tolerance Of The Operating Frequency":"-10%","Relative Positive Tolerance Of The Operating Frequency":"10%","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":"45W","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":"15A","Relative Negative Tolerance Of The Operating Voltage At Inside-Delta Circuit":"-15%","Relative Positive Tolerance Of The Operating Voltage At Inside-Delta Circuit":"10%"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/c3e1deeed4c95cb50dc17cdeae72264f.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=103001&mlfb=3RW4426-3BC45"},"ai":{"faq":[{"question":"What is the maximum current at 60 °C ambient?","answer":"102 A at 60 °C, down from 133 A at 40 °C. The integrated bypass reduces continuous heat load inside the panel."},{"question":"Can this soft starter be wired in inside-delta configuration?","answer":"Yes, inside-delta circuit is supported. This lets you use a lower-rated unit for six-lead motors, reducing cost and panel space."},{"question":"What terminals does the control circuit use?","answer":"The main circuit uses box terminals for 2× (4 … 50 mm²) stranded."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4426-3BC45","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/3RW4426-3BC45 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}