{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4453-2BC45","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4453-2BC45","canonicalUrl":"https://aoctrl.com/siemens/3RW4453-2BC45","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4453-2BC45","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4453-2BC45 soft starter, 954 A at 40 °C, 690 V insulation voltage, 50/60 Hz, with integrated bypass and adjustable current limitation.","salesMarkdown":"## 954 A at 40 °C — derating curve matters for the panel build The 3RW4453-2BC45: That derating slope means the panel ventilation and mounting position directly set the usable current — screw-fixed to a vertical surface, rotatable ±90° and tiltable ±22.5°, so you can orient it to pull cooler air across the heatsink. Insulation voltage rated 690 V, pollution degree 3 per IEC 60947-4-2, so it handles the typical 400–690 V industrial mains with margin for transient overvoltage in dirty environments. ## Integrated bypass and inside-delta wiring Built-in bypass contact system means the thyristors are shorted out once the motor is up to speed — no external bypass contactor needed, and the heat load in the panel drops to near zero during run. The inside-delta circuit option lets you wire the soft starter between the motor windings instead of in-line, reducing the current the unit sees by a factor of √3; useful for retrofitting into existing motor terminal boxes where cable routing is tight. Adjustable current limitation from 8% minimum load lets you dial in the start current to match the supply transformer capacity or generator set — set it just above the motor's no-load magnetizing current and the ramp is smooth without tripping upstream breakers. ## Motor overload and intrinsic device protection onboard Motor overload protection is integrated — no separate overload relay needed for the soft starter branch circuit. Intrinsic device protection monitors the thyristor junction temperature and shuts down before the semiconductor exceeds its SOA, which is the failure mode that takes out un-protected soft starters on a stalled-rotor start. External reset input and a display for fault signals mean the maintenance team gets a readable fault code without plugging in a laptop. The motor brake output component is built in, so a DC injection brake can be wired directly without an extra contactor. ## Termination and wire sizing for the main circuit Main current circuit termination is busbar connection — no lugs to crimp, just bolt the busbar directly. The stranded wire range is 70–240 mm², finely stranded 50–240 mm², and for North American builds it accepts 2/0–500 kcmil. Physical footprint: 510 mm wide, 640 mm high, 290 mm deep. Clearance requirements: 100 mm above, 75 mm below, 5 mm at the sides. Maximum motor cable length is 500 m — beyond that the cable capacitance can cause nuisance thyristor firing from leakage current.","metaTitle":"Siemens 3RW4453-2BC45 SIRIUS Soft Starter, 954 A, 690 V","metaDescription":"Siemens 3RW4453-2BC45 SIRIUS soft starter, rated 954 A at 40 °C, 690 V insulation voltage. 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":"3RW4453-2BC45","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: 551 A, 355 kW Inside-delta: 954 A, 630 kW 400-600 V AC, 230 V AC spring-type terminals!!! Phased-out product!!! Successor is SIRIUS 3RW5, Preferred successor type is >>3RW5548-2HA16<<","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":"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":"355kW","at standard circuit at 50 °C rated value":"500hp","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":"630kW","at inside-delta circuit at 50 °C rated value":"950hp","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":"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/227d04beaf7354e093fd40a7a8620ea2.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=170863&mlfb=3RW4453-2BC45"},"ai":{"faq":[{"question":"What is the 3RW4453-2BC45 rated current at different temperatures?","answer":"Rated 954 A at 40 °C, derating to 856 A at 50 °C and 759 A at 60 °C. The derating temperature threshold is 40 °C — above that, usable current drops linearly."},{"question":"Does the 3RW4453-2BC45 include a bypass contactor?","answer":"Yes, the integrated bypass contact system is built in. Once the motor reaches full speed the thyristors are shorted out, so no external bypass contactor is required."},{"question":"What wire sizes does the 3RW4453-2BC45 accept for the main power circuit?","answer":"Main circuit termination is busbar connection. Stranded wire range 70–240 mm², finely stranded 50–240 mm², and 2/0–500 kcmil for North American builds."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4453-2BC45","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/3RW4453-2BC45 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}}