{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4028-2BB15","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4028-2BB15","canonicalUrl":"https://aoctrl.com/siemens/3RW4028-2BB15","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4028-2BB15","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4028-2BB15 soft starter, size S0, 38 A at 40 °C, 50/60 Hz, 110–230 VDC control supply, integrated bypass and overload protection, spring-loaded terminals, screw and snap-on mounting.","salesMarkdown":"## 38 A at 40 °C — the rating that governs the motor branch The 3RW4028-2BB15: If your panel ambient runs above 40 °C — common in a packed enclosure with a drive below — you need to budget the lower number, not the catalogue headline. The control supply accepts 110–230 VDC, wide enough to ride through a sagging DC bus without dropping out the logic. Operating frequency is 50/60 Hz, so it tracks line frequency without parameter adjustment. ## Integrated bypass and overload — one device, fewer panel connections An integrated bypass contact system means the thyristors are shorted out once the motor reaches full speed. This eliminates the external bypass contactor you would otherwise need to size and wire, and it drops the heat load inside the panel during continuous run. The soft starter also includes motor overload protection and adjustable current limitation, so a separate overload relay is not required for most applications. Power and control connections use spring-loaded terminals — no screw torque to verify, no loosening under thermal cycling. Mounting is screw-and-snap-on to DIN rail. The S0 frame is 45 mm wide, 150 mm tall, 155 mm deep — a 3-module footprint that leaves room alongside a contactor or overload block. Clearance above the device is 60 mm, below is 40 mm, and 15 mm at the sides. ## Active production — sourced per BOM Pollution degree 3 per IEC 60947-4-2 means the device is rated for the conductive-dust and condensation environment you find in a typical industrial panel — not a clean-room or climate-controlled switchroom. Storage temperature range is -40 to +80 °C; operating ambient is -25 to +60 °C.","metaTitle":"Siemens 3RW4028-2BB15 SIRIUS Soft Starter, 38A at 40°C","metaDescription":"Siemens 3RW4028-2BB15 SIRIUS soft starter, 38 A rated at 40 °C, integrated bypass and overload protection. Active production, quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Soft Starters"],"specifications":{"Depth":"155mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"45mm","title":"3RW4028-2BB15","Height":"150mm","Upwards":"60mm","Downwards":"40mm","Thyristors":"Yes","At The Side":"15mm","description":"SIRIUS soft starter S0 38 A, 22 kW/500 V, 40 °C 400-600 V AC, 110-230 V AC/DC spring-type terminals","During Storage":"-40 ... +80°C","External Reset":"Yes","lifecycle_stage":"current","During Operation":"-25 ... +60°C","Fastening Method":"screw and snap-on mounting","Minimum Load [%]":"20%","For Main Contacts":"16 ... 10, 1x 8","Mounting Position":"With additional fan: With vertical mounting surface +/-90° rotatable, with vertical mounting surface +/- 22.5° tiltable to the front and back Without additional fan: With vertical mounting surface +/-10° rotatable, with vertical mounting surface +/- 10° t","Product Brand Name":"SIRIUS","Degree Of Pollution":"3, acc. to IEC 60947-4-2","Product Designation":"Soft starter","Wire Length Maximum":"300m","Derating Temperature":"40°C","Inside-Delta Circuit":"No","at 40 °C rated value":"38A","at 50 °C rated value":"34A","at 60 °C rated value":"31A","For Auxiliary Contacts":"2x (24 ... 14)","For Main Current Circuit":"spring-loaded terminals","Motor Overload Protection":"Yes","Intrinsic Device Protection":"Yes","Adjustable Current Limitation":"Yes","Size Of Engine Control Device":"S0","Insulation Voltage Rated Value":"600V","Using The Front Clamping Point":"1x 8, 2x (16 ... 10)","control supply voltage 1 at DC":"110 ... 230V","Operating Frequency Rated Value":"50 ... 60Hz","Display Version For Fault Signal":"red","Integrated Bypass Contact System":"Yes","For Auxiliary And Control Circuit":"spring-loaded terminals","Product Component Motor Brake Output":"No","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","control supply voltage 1 at AC at 50 Hz":"110 ... 230V","control supply voltage 1 at AC at 60 Hz":"110 ... 230V","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":"No","at standard circuit at 40 °C rated value":"22kW","at standard circuit at 50 °C rated value":"30hp","number of CO contacts for auxiliary contacts":"1","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"2","Type Of Voltage Of The Control Supply Voltage":"AC/DC","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","Relative Negative Tolerance Of The Operating Frequency":"-10%","Relative Positive Tolerance Of The Operating Frequency":"10%","relative negative tolerance of the control supply voltage at DC":"-15%","relative positive tolerance of the control supply voltage at DC":"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":"19W","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":"23A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/b5af4d19c2b352c28d3e11efa3f48e58.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=356136&mlfb=3RW4028-2BB15"},"ai":{"faq":[{"question":"How do I get pricing and availability for the 3RW4028-2BB15?","answer":"The 3RW4028-2BB15 is sourced to order through authorized distribution. No stock-holding claim is made here — each order is quoted fresh against the BOM."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4028-2BB15","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/3RW4028-2BB15 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}}