{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4453-2BC44","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4453-2BC44","canonicalUrl":"https://aoctrl.com/siemens/3RW4453-2BC44","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4453-2BC44","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4453-2BC44 soft starter, 954 A at 40 °C, 690 V insulation voltage, 50/60 Hz, 3-phase, integrated bypass contact system, inside-delta circuit, screw fixing, IP20.","salesMarkdown":"## Current rating and thermal derating — the real operating envelope The 3RW4453-2BC44: The derating temperature threshold is 40 °C — above that, the continuous current drops linearly per the datasheet curve. For a panel with an internal ambient of 50 °C, budget 856 A as the usable ceiling; the 60 °C figure (759 A) applies only if the enclosure ventilation keeps the air around the unit below that limit. The insulation voltage is rated 690 V, with an operating frequency range of 50 to 60 Hz. ## Integrated bypass and inside-delta topology An integrated bypass contact system is built into the unit — once the motor reaches full speed, the thyristors are shorted out, eliminating heat dissipation from the semiconductor stack during continuous run. This means the enclosure thermal budget is set by the bypass contactor losses, not the silicon junction temperature. The unit supports inside-delta circuit wiring, which connects the soft starter in the delta legs of a six-lead motor. This reduces the current through each thyristor to 58% of the line current, effectively extending the current range of the unit without increasing the semiconductor die size. Verify the motor has six accessible leads before specifying this topology. ## Protection functions and control features Motor overload protection is integral — the unit monitors motor current and trips on overload without requiring an external overload relay. Intrinsic device protection covers the thyristors against over-temperature and over-current, and the adjustable current limitation lets you set the start current between 8% and 100% of the rated current. An external reset input is provided, allowing remote reset of the fault condition from a PLC or pushbutton station. The display shows fault codes directly on the unit, reducing troubleshooting time. A motor brake output is included as a product component — this can control a DC injection brake or mechanical brake coil without an additional interface relay. ## Mounting, wiring, and clearance dimensions The unit measures 640 mm high, 510 mm wide, and 290 mm deep. Fastening is by screw fixing (not DIN-rail clip) — the enclosure backplate must have drilled and tapped holes matching the mounting pattern. The mounting position allows vertical surface mounting with +/-90° rotation and +/-22.5° tilt forward/backward, giving flexibility in panel layout. Minimum clearance requirements: 100 mm above, 75 mm below, and 5 mm at the sides. Maximum motor cable length is 500 m — beyond this, capacitive charging current may cause nuisance tripping or thyristor misfiring. The pollution degree is 3 per IEC 60947-4-2, meaning the unit is suitable for industrial environments with conductive dust or occasional condensation. ## Environmental limits and storage conditions During operation, the ambient temperature must not exceed 60 °C. Storage temperature range is -25 to +80 °C — this applies to the unit in its original packaging, not installed in a panel. The product brand is SIRIUS, and the product designation is 'Soft starter' per the Siemens catalog.","metaTitle":"Siemens 3RW4453-2BC44 SIRIUS Soft Starter, 954 A at 40 °C","metaDescription":"Siemens 3RW4453-2BC44 SIRIUS soft starter, 954 A at 40 °C, 690 V insulation, 50/60 Hz. Active production, quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Soft Starters"],"specifications":{"Depth":"290mm","Solid":"2x (0.25 ... 1.5 mm²)","Width":"510mm","title":"3RW4453-2BC44","Height":"640mm","Upwards":"100mm","Stranded":"70 ... 240 mm²","Downwards":"75mm","Thyristors":"Yes","At The Side":"5mm","description":"SIRIUS soft starter Values at 400 V, 40 °C standard: 551 A, 315 kW Inside-delta: 954 A, 560 kW 200-460 V AC, 230 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5548-2HA14<<","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":"954A","at 50 °C rated value":"856A","at 60 °C rated value":"759A","For Auxiliary Contacts":"2x (24 ... 16)","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":"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","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":"560kW","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":"200 ... 460V","contact rating of auxiliary contacts according to UL":"B300 / R300","Operating Voltage At Inside-Delta Circuit Rated Value":"200 ... 460V","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":"159W","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":"110A","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/579f19d676fef80e2424dec1e785814c.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=274554&mlfb=3RW4453-2BC44"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4453-2BC44","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/3RW4453-2BC44 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}}