{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4425-3BC35","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4425-3BC35","canonicalUrl":"https://aoctrl.com/siemens/3RW4425-3BC35","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4425-3BC35","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4425-3BC35 soft starter, 99 A at 40 °C, 690 V insulation voltage, 50/60 Hz, integrated bypass contact system, screw fixing.","salesMarkdown":"## Motor starting with integrated bypass The 3RW4425-3BC35: It includes an integrated bypass contact system, so once the motor reaches full speed, the thyristors are shorted and heat dissipation drops to near zero — no external bypass contactor needed. Current derating is linear: 88 A at 50 °C and 78 A at 60 °C, with derating starting above 40 °C. The minimum load is 8% of the rated current, which matters for lightly loaded motors or pumps that start near empty. ## Panel fit and wiring The unit measures 192 mm high by 170 mm wide by 270 mm deep, mounts via screw fixing, and allows vertical mounting with ±90° rotation and ±22.5° tilt front-to-back — useful when retrofitting into an existing enclosure where the backplate is already drilled. Main circuit connections use box terminals accepting 2x (4 to 50 mm²) stranded or 2x (10 to 1/0 AWG) with both clamping points. Maximum motor cable length is 500 m — sufficient for most distributed motor installations without a output reactor, though long runs in high-capacitance cable may still need one depending on the installation. ## Protection and control features Built-in motor overload protection and intrinsic device protection are standard. The adjustable current limitation lets you set the starting current between the minimum load of 8% and the rated current, reducing mechanical shock on the driven load. The soft starter supports inside-delta circuit wiring, which reduces the current through the thyristors by a factor of √3 compared to standard in-line connection — useful for larger motors where the soft starter frame size can be reduced. An external reset input and a display for fault signals are provided, so the starter can be reset from a remote panel without opening the enclosure door. ## Environmental and compliance Operating temperature range is up to 60 °C; storage range is -25 to +80 °C.","metaTitle":"Siemens 3RW4425-3BC35 SIRIUS Soft Starter, 99 A at 40 °C","metaDescription":"Siemens 3RW4425-3BC35 SIRIUS soft starter, 99 A at 40 °C, 690 V insulation, integrated bypass. Active production, quoted to order. Request a quote.","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":"3RW4425-3BC35","Height":"192mm","Upwards":"100mm","Stranded":"2x (4 ... 50 mm²)","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter Values at 575 V, 50 °C standard: 51 A, 40 hp Inside-delta: 88 A, 75 hp 400-600 V AC, 115 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5525-3HA16<<","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":"115V","at 60 Hz rated value":"115V","at 40 °C rated value":"99A","at 50 °C rated value":"88A","at 60 °C rated value":"78A","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":"37kW","at standard circuit at 50 °C rated value":"40hp","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":"55kW","at inside-delta circuit at 50 °C rated value":"75hp","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":"36W","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":"11A","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/ea7fd30dff6f4b4e80483f6a01fa44b1.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=274367&mlfb=3RW4425-3BC35"},"ai":{"faq":[{"question":"What is the maximum motor cable length for 3RW4425-3BC35?","answer":"The maximum motor cable length is 500 m. For installations with long runs of high-capacitance cable, an output reactor may still be needed depending on the specific drive and cable type."},{"question":"Does 3RW4425-3BC35 support inside-delta wiring?","answer":"Yes, it supports inside-delta circuit wiring, which reduces the current through the thyristors by a factor of √3 compared to standard in-line connection. This is useful for larger motors where a smaller soft starter frame can be used."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4425-3BC35","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/3RW4425-3BC35 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}}