{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4447-2BC45","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4447-2BC45","canonicalUrl":"https://aoctrl.com/siemens/3RW4447-2BC45","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4447-2BC45","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4447-2BC45 soft starter, 748 A at 40 °C, 690 V insulation, 50/60 Hz, inside-delta circuit, screw fixing, 298 x 210 x 230 mm.","salesMarkdown":"## 748 A at 40 °C — the real continuous rating The 3RW4447-2BC45: That derating curve is the one that governs panel placement — if your enclosure runs hot, the available current drops. The 690 V insulation voltage (IEC 60947-4-2, pollution degree 3) means it handles industrial environments with conductive dust or condensation without tracking. Operating frequency is 50/60 Hz, same coil rating at both line frequencies — no reconfiguration needed when crossing 50/60 Hz regions. ## Inside-delta topology and thyristor bank This is an inside-delta soft starter with thyristor control. Inside-delta wiring means the thyristors sit inside the motor delta connection rather than in the line — reduces the current through the power semiconductors compared to a standard line-fed starter, which is why this unit can handle 748 A in a single chassis. The thyristor bank handles the ramp-up; once at speed, the motor runs across the line through the bypass contactor (not included). Minimum load is 8% of rated current — important if you're starting a lightly loaded pump or conveyor and the starter needs to detect the motor current for protection. ## Mounting and connection flexibility Mounts with screw fixing, vertical surface, rotatable ±90° and tiltable ±22.5° front/back — gives you options when the panel layout is tight. Dimensions are 298 mm deep, 210 mm wide, 230 mm high. Clearance: 100 mm above, 75 mm below, 5 mm at the sides — the side clearance is minimal, so you can pack units close together horizontally. Main circuit connection: busbar or cable. Accepts stranded 70–240 mm², finely stranded 50–240 mm², and AWG 2/0–500 kcmil. The dual clamping points let you parallel two cables per phase — useful when the cable ampacity requires parallel runs. Maximum motor lead length is 500 m — if your motor is farther than that from the starter, you'll need an output reactor or filter to prevent reflected wave damage to the motor insulation. ## Protection and diagnostics onboard Built-in motor overload protection and intrinsic device protection (monitors the thyristor junction temperature and shuts down before damage). Adjustable current limitation lets you set the starting current ceiling as a percentage of the motor FLA. External reset input for remote fault clearing. Display shows fault codes — no guessing which trip hit first.","metaTitle":"Siemens 3RW4447-2BC45 SIRIUS Soft Starter, 748 A at 40 °C","metaDescription":"Siemens SIRIUS 3RW4447-2BC45 soft starter, 748 A at 40 °C, 690 V insulation, inside-delta circuit. Active production, quoted to order against your BOM.","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":"3RW4447-2BC45","Height":"230mm","Upwards":"100mm","Stranded":"70 ... 240 mm²","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter Values at 500 V, 40 °C standard: 432 A, 315 kW Inside-delta: 748 A, 500 kW 400-600 V AC, 230 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5547-2HA16<<","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":"230V","at 60 Hz rated value":"230V","at 40 °C rated value":"748A","at 50 °C rated value":"667A","at 60 °C rated value":"580A","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":"315kW","at standard circuit at 50 °C rated value":"400hp","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":"500kW","at inside-delta circuit at 50 °C rated value":"750hp","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":"232W","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":"86A","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/549c01a0d9793100816e91f894a6aba8.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=427660&mlfb=3RW4447-2BC45"},"ai":{"faq":[{"question":"Where can I buy the 3RW4447-2BC45 and get a price?","answer":"We source it through independent distribution channels. Send an RFQ with your quantity and target delivery window — we confirm availability and current pricing at quote time. No stock-holding claim; every order is confirmed against live channel inventory."},{"question":"What are the main circuit connection options for the 3RW4447-2BC45?","answer":"Busbar connection or cable. Accepts stranded 70–240 mm², finely stranded 50–240 mm², and AWG 2/0–500 kcmil. Dual clamping points allow paralleling two cables per phase. The back clamping point handles 250–500 kcmil, the front clamping point 3/0–600 kcmil."},{"question":"What does inside-delta circuit mean for this soft starter?","answer":"Inside-delta wiring places the thyristors inside the motor delta connection rather than in the supply lines. This reduces the current through the power semiconductors, allowing a smaller chassis for the same motor current. The motor runs across the line after starting — a bypass contactor is required externally."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4447-2BC45","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/3RW4447-2BC45 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}}