{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4443-2BC35","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4443-2BC35","canonicalUrl":"https://aoctrl.com/siemens/3RW4443-2BC35","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4443-2BC35","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4443-2BC35 soft starter, 352 A at 40 °C, 312 A at 50 °C, 270 A at 60 °C, 690 V insulation, 50/60 Hz, inside-delta circuit, adjustable current limitation, motor overload protection, pollution degree 3 per IEC 60947-4-2.","salesMarkdown":"## 352 A at 40 °C — what that means for your motor circuit The 3RW4443-2BC35: The 40 °C figure is the standard rating; above that, derate per the temperature curve. Insulation voltage is 690 V, operating frequency 50/60 Hz. It supports inside-delta wiring — that means the soft starter connects in the delta leg of a six-lead motor, reducing the current through each phase by a factor of √3 compared to inline connection. The adjustable current limitation lets you set the start current between 8% and 100% of the rated motor FLA, which is useful for soft starting high-inertia loads without tripping upstream protection. Motor overload protection is built in, along with intrinsic device protection — the unit monitors its own thyristor junction temperature and shuts down before damage. Pollution degree 3 per IEC 60947-4-2 means it's rated for industrial environments with conductive pollution; no additional conformal coating is required for most panel installations. ## Mounting, wiring, and panel fit Dimensions are 230 mm height, 210 mm width, 298 mm depth. Fastening is screw fixing — no DIN-rail clip, so plan for a backplate with drilled holes. Mounting position is flexible: vertical surface with ±90° rotation and ±22.5° tilt front/back. Main current circuit connection is via busbar, with a range of cable sizes: stranded 70–240 mm², finely stranded 50–240 mm², and kcmil 2/0–500. The busbar clamping points accept up to 2x 500 kcmil or a single 250–500 kcmil back clamp. Clearance requirements: 100 mm above, 75 mm below, 5 mm at the sides. Maximum motor cable length is 500 m — beyond that, capacitive charging current may cause nuisance trips. Storage temperature range is -25 to +80 °C; operating ambient max is 60 °C.","metaTitle":"Siemens 3RW4443-2BC35 SIRIUS Soft Starter, 352 A at 40 °C","metaDescription":"Siemens 3RW4443-2BC35 SIRIUS soft starter, rated 352 A at 40 °C, 690 V insulation, 50/60 Hz. Active production, sourced to order. Request a quote.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"298mm","Solid":"2x (0.25 ... 1.5 mm²)","Width":"210mm","title":"3RW4443-2BC35","Height":"230mm","Upwards":"100mm","Stranded":"70 ... 240 mm²","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter Values at 575 V, 50 °C standard: 180 A, 150 hp Inside-delta: 312 A, 300 hp 400-600 V AC, 115 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5543-2HA16<<","During Storage":"-25 ... +80°C","External Reset":"Yes","Finely Stranded":"50 ... 240 mm²","lifecycle_stage":"current","During Operation":"60°C","Fastening Method":"screw fixing","Minimum Load [%]":"8%","For Main Contacts":"2/0 ... 500 kcmil","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":"352A","at 50 °C rated value":"312A","at 60 °C rated value":"270A","For Auxiliary Contacts":"2x (24 ... 16)","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","Using The Back Clamping Point":"250 ... 500 kcmil","Insulation Voltage Rated Value":"690V","Using The Front Clamping Point":"3/0 ... 600 kcmil","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":"132kW","at standard circuit at 50 °C rated value":"150hp","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":"3","Type Of Voltage Of The Control Supply Voltage":"AC","at inside-delta circuit at 40 °C rated value":"250kW","at inside-delta circuit at 50 °C rated value":"300hp","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":"89W","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":"40A","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/398eb001d65773d4318a1977472a0c34.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=429819&mlfb=3RW4443-2BC35"},"ai":{"faq":[{"question":"What is the 3RW4443-2BC35 rated for at 40 °C?","answer":"352 A at 40 °C ambient. Insulation voltage is 690 V, operating frequency 50/60 Hz."},{"question":"Does the 3RW4443-2BC35 support inside-delta wiring?","answer":"Yes, it supports inside-delta circuit connection. This allows the soft starter to handle higher motor currents by connecting in the delta leg of a six-lead motor, reducing per-phase current by √3."},{"question":"What are the clearance requirements for mounting?","answer":"100 mm above, 75 mm below, 5 mm at the sides. Mounting is screw fixing with a vertical surface; the unit can be rotated ±90° and tilted ±22.5° front/back."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4443-2BC35","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/3RW4443-2BC35 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}}