{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4425-1BC36","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4425-1BC36","canonicalUrl":"https://aoctrl.com/siemens/3RW4425-1BC36","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4425-1BC36","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4425-1BC36 soft starter, 99 A at 40 °C, 690 V insulation voltage, 50/60 Hz, thyristor control with integrated bypass contactor, screw fixing, 270 x 170 x 192 mm.","salesMarkdown":"## Thyristor soft starter with integrated bypass — 99 A at 40 °C The 3RW4425-1BC36: It uses thyristor control for the starting ramp and integrates a bypass contactor that shorts the semiconductors after start, eliminating heat dissipation in the power section during run. The unit delivers 88 A at 50 °C and 78 A at 60 °C — the derating curve matters when the panel ambient runs above 40 °C. The minimum load threshold is 8 % of the rated current, so it handles lightly loaded motors without dropping out. ## Current derating and thermal management in the panel Rated current drops from 99 A at 40 °C to 88 A at 50 °C and 78 A at 60 °C — a 21 % reduction from the 40 °C baseline to the 60 °C ceiling. The derating temperature threshold is 40 °C; above that the output must be linearly reduced per the datasheet curve. Clearance requirements for natural convection cooling: 100 mm above, 75 mm below, and 5 mm at the sides. The mounting position allows vertical surface orientation with ±90° rotation and ±22.5° tilt forward/backward, which affects hot-air rise paths. The unit is fastened by screw fixing (not DIN-rail clip), so the panel backplate must have drilled and tapped mounting points matching the 170 mm width and 192 mm height footprint. ## Wiring, protection, and control interface The back and front clamping points accept 10... 2/0 AWG; using both clamping points accepts 2x (10... 1/0 AWG). Maximum motor cable length is 500 m. Motor overload protection is built in, with adjustable current limitation and intrinsic device protection. An external reset input is provided, and the fault signal is shown on an integrated display. Auxiliary contacts use 2x (20... 14) terminals. Pollution degree 3 per IEC 60947-4-2 means it tolerates conductive pollution in industrial environments. Ambient limits: -25 to +80 °C storage, 60 °C max during operation. The inside-delta circuit wiring option is supported, which reduces the starter current rating by a factor of √3 compared to standard in-line connection — useful for retrofit into existing delta-wound motor circuits without changing the motor terminal box.","metaTitle":"Siemens 3RW4425-1BC36 SIRIUS Soft Starter, 99 A at 40 °C","metaDescription":"Siemens 3RW4425-1BC36 SIRIUS soft starter, 99 A rated at 40 °C, 690 V insulation voltage, integrated bypass, thyristor control.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"270mm","Solid":"2x (0.5 ... 2.5 mm²)","Width":"170mm","title":"3RW4425-1BC36","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 400-690 V AC, 115 V AC Screw terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5525-1HA16<<","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 (20 ... 14)","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","during storage acc. to IEC 60721":"1K6 (only occasional condensation), 1C2 (no salt mist), 1S2 (sand must not get inside the devices), 1M4","For Auxiliary And Control Circuit":"screw-type terminals","during operation acc. 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 acc. to IEC 60721":"2K2, 2C1, 2S1, 2M2 (max. fall height 0.3 m)","Product Component Motor Brake Output":"Yes","reference code acc. to DIN EN 61346-2":"Q","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":"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","touch protection on the front acc. to IEC 60529":"finger-safe, for vertical contact from the front","continuous operating current [% of Ie] at 40 °C":"115%","Operating Voltage At Standard Circuit Rated Value":"400 ... 690V","at 690 V at standard circuit at 40 °C rated value":"55kW","protection class IP on the front acc. to IEC 60529":"IP20","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%","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":"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/a7488bd22170941f6b7147b7d17ddc20.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=357805&mlfb=3RW4425-1BC36"},"ai":{"faq":[{"question":"What clearance is needed around the 3RW4425-1BC36 for cooling?","answer":"Minimum clearances are 100 mm above, 75 mm below, and 5 mm at the sides. The unit is screw-fixed (not DIN-rail mounted) and allows vertical surface orientation with ±90° rotation and ±22.5° tilt."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4425-1BC36","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/3RW4425-1BC36 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}}