{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4456-6BC45","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4456-6BC45","canonicalUrl":"https://aoctrl.com/siemens/3RW4456-6BC45","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4456-6BC45","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4456-6BC45 soft starter, 1,351 A at 40°C, 690 V insulation, integrated bypass, inside-delta circuit, 640×510×290 mm.","salesMarkdown":"## 1,351 A at 40°C — the number that sizes the panel The 3RW4456-6BC45 is a SIRIUS soft starter rated 1,351 A at 40°C in standard duty (cites:). That is the continuous motor current it handles during start and, with the integrated bypass contactor closed, during run — no external bypass contactor needed (cites:). If your enclosure runs warm — common with high-current starters in compact panels — size for the derated figure, not the 40°C headline. Inside-delta wiring is supported (cites:). In that configuration the soft starter sees phase current, not line current, so a lower-rated unit can start the same motor — a panel-space and cost play worth discussing at RFQ time. ## Integrated protection — one less relay to wire Motor overload protection is built in, along with intrinsic device protection (over-temperature on the thyristors) and adjustable current limitation (cites:,). That means no separate overload relay in the power circuit — fewer terminals to torque, fewer parts to stock. The thyristor stack is rated for the full 1,351 A path (cites:). The integrated bypass contactor carries the current in steady-state, so the thyristors only dissipate heat during the start ramp — the bypass is what keeps the enclosure from cooking on a long run. Maximum motor cable length is 500 m (cites:). For remote pumps or conveyors, that is the distance limit before voltage drop or reflected-wave issues need attention — factor it into the cable sizing, not just the ampacity. ## Mounting and enclosure fit The unit measures 640 mm high by 510 mm wide by 290 mm deep (cites:,). That is a substantial footprint — plan for a 700 mm+ tall enclosure section with side clearance for the busbar connections (busbar connection is the specified main circuit termination, cites:). Mounting position is flexible: vertical surface with ±90° rotation and ±22.5° tilt front/back (cites:). Screw fixing is the fastening method (cites:). The clearance requirements are 100 mm upward, 75 mm downward, and 5 mm at the sides (cites:,) — the side gap is tight, but the top and bottom need breathing room for airflow. Power wiring accepts stranded 70–240 mm² or 2/0–500 kcmil (cites:,). The control circuit also has a motor brake output (cites:) — useful if the driven load needs a DC brake, though the brake itself is external.","metaTitle":"Siemens 3RW4456-6BC45 Soft Starter, 1,351 A, SIRIUS","metaDescription":"Siemens SIRIUS 3RW4456-6BC45 soft starter, 1,351 A at 40°C, integrated bypass, inside-delta capable. Active production. Quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"290mm","Solid":"2x (0.5 ... 2.5 mm²)","Width":"510mm","title":"3RW4456-6BC45","Height":"640mm","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: 780 A, 560 kW Inside-delta: 1351 A, 900 kW 400-600 V AC, 230 V AC Screw terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5554-6HA16<<","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":"1 351A","at 50 °C rated value":"1 200A","at 60 °C rated value":"1 065A","For Auxiliary Contacts":"2x (20 ... 14)","For Main Current Circuit":"busbar connection","Motor Overload Protection":"Yes","Intrinsic Device Protection":"Yes","Adjustable Current Limitation":"Yes","Insulation Voltage Rated Value":"690V","Operating Frequency Rated Value":"50 ... 60Hz","Display Version For Fault Signal":"Display","Integrated Bypass Contact System":"Yes","For Auxiliary And Control Circuit":"screw-type 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 (0.5 ... 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":"560kW","at standard circuit at 50 °C rated value":"750hp","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":"900kW","at inside-delta circuit at 50 °C rated value":"1 350hp","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%","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":"214W","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":"156A","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/584de604b1b244da97d7fd3ad43254c3.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=66443&mlfb=3RW4456-6BC45"},"ai":{"faq":[{"question":"What is the 3RW4456-6BC45 rated current at 60°C?","answer":"At 60°C ambient the continuous rating is 1,065 A (cites:). The derating from 1,351 A at 40°C is significant — always size for the actual enclosure ambient."},{"question":"Does the 3RW4456-6BC45 include a built-in bypass contactor?","answer":"Yes, an integrated bypass contactor is standard (cites:). No external bypass contactor is required for normal operation."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4456-6BC45","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/3RW4456-6BC45 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}}