{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4453-2BC35","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4453-2BC35","canonicalUrl":"https://aoctrl.com/siemens/3RW4453-2BC35","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4453-2BC35","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4453-2BC35 soft starter, 954 A at 40 °C, 690 V insulation voltage, inside-delta circuit, integrated bypass contact system, screw fixing.","salesMarkdown":"That 954 A figure is the full-load current it can handle in standard duty — sized for a motor pulling that current, not a peak surge. The 690 V insulation rating means it's fit for 400 V and 480 V systems with headroom, and it's rated for pollution degree 3 per IEC 60947-4-2, which is the industrial environment where conductive dust or condensation can occur — standard for motor control centers. The soft starter uses thyristors and includes an integrated bypass contact system, which means once the motor is up to speed, the bypass contactor closes and the thyristors are shunted out. That eliminates heat dissipation from the semiconductors during continuous run, so the enclosure doesn't need oversized ventilation for the running condition. It also provides motor overload protection and intrinsic device protection, so a separate overload relay is not required — the soft starter handles that function internally. The minimum load is 8% of the rated current, which means it can start lightly loaded motors or pumps without the thyristors failing to trigger — a common issue on soft starters when the load is too low for the firing circuit. Adjustable current limitation lets you set the start current between that minimum and the full rating, so you can tune the start profile to the load. ## Inside-delta and wiring This soft starter supports inside-delta circuit configuration, which is a wiring method where the soft starter sits inside the motor's delta connection rather than in the supply lines. That reduces the current through the thyristors to 58% of the line current, so a 954 A unit can effectively control a motor drawing more than 954 A line current — useful for squeezing a larger motor onto a given soft starter frame. The main current circuit uses busbar connection, not cable lugs, so the panel builder needs to plan for busbar drops rather than ring terminals. The main contact wiring accepts stranded 70 to 240 mm², finely stranded 50 to 240 mm², or AWG 2/0 to 500 kcmil. Auxiliary and control circuits use spring-loaded terminals accepting solid 2x (0.25 to 1.5 mm²) or AWG 24 to 16. The maximum wire length to the motor is 500 m — beyond that, voltage drop and reflected wave issues can affect the thyristor commutation. Mounting is by screw fixing on a vertical surface, rotatable ±90° and tiltable ±22.5° front-to-back. Clearance requirements: 100 mm upwards, 75 mm downwards, and only 5 mm at the sides — so it fits tightly between other devices in a lineup. The dimensions are 640 mm high, 510 mm wide, and 290 mm deep. The operating frequency is 50 to 60 Hz, and the control supply voltage is 115 V at both 50 Hz and 60 Hz. The unit includes a display for fault signals, an external reset input, and a motor brake output component — so it can directly control a brake on the motor shaft without a separate contactor.","metaTitle":"Siemens 3RW4453-2BC35 SIRIUS Soft Starter, 954 A","metaDescription":"Siemens 3RW4453-2BC35 SIRIUS soft starter, 954 A at 40 °C, 690 V insulation, inside-delta capable, integrated bypass.","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":"3RW4453-2BC35","Height":"640mm","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: 494 A, 500 hp Inside-delta: 856 A, 950 hp 400-600 V AC, 115 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":"115V","at 60 Hz rated value":"115V","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/5c323ff8f88b7484f7393a7249d53e7b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=205727&mlfb=3RW4453-2BC35"},"ai":{"faq":[{"question":"What is the replacement for Siemens 3RW4453-2BC35?","answer":"There is no replacement for the 3RW4453-2BC35 because it is the current production version. No official successor order code has been issued. If your BOM calls this exact order code, the part is the correct fit."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4453-2BC35","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/3RW4453-2BC35 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}}