{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW3028-2BB04","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW3028-2BB04","canonicalUrl":"https://aoctrl.com/siemens/3RW3028-2BB04","factsUrl":"https://aoctrl.com/api/mcp/products/3RW3028-2BB04","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW3028-2BB04 soft starter, size S0, 38 A at 40 °C, 600 V insulation, integrated bypass, spring-loaded terminals, 45 mm width, active production.","salesMarkdown":"## 38 A at 40 °C — the derating curve matters for enclosure fit The 3RW3028-2BB04: That 40 °C derating temperature means if the panel ambient runs hotter — common in a packed cabinet with drives and contactors — you lose nearly 20 % of the rated current. Size the enclosure ventilation or step up one frame if the motor FLA sits above 31 A at your worst-case ambient. The integrated bypass contact system eliminates the external bypass contactor and its wiring — the soft starter's thyristors only handle the start ramp, then the bypass relay carries the run current. This saves panel space and cuts heat dissipation during continuous operation. ## S0 frame — panel integration and wiring Size S0 means a 45 mm wide housing, 150 mm deep, with screw and snap-on mounting for DIN rail or direct panel screw. The 150 mm depth fits standard 200 mm deep enclosures with clearance for the 60 mm upward and 40 mm downward wiring space. Side clearance is 15 mm — tight for multi-unit ganging, so check heat dissipation if mounting several side-by-side. Spring-loaded terminals on both the main current circuit and the auxiliary/control circuit — tool-less insertion for solid or ferruled stranded wire. Main terminals accept 16 to 8 AWG; auxiliary terminals accept 24 to 14 AWG. The front clamping point handles 1x 8 AWG or 2x 16 to 10 AWG for daisy-chaining. ## Lifecycle and sourcing — active, quoted to order The 50/60 Hz operating frequency covers global line supplies. No motor overload protection or adjustable current limitation — plan for an external overload relay and fixed ramp profile.","metaTitle":"Siemens 3RW3028-2BB04 Soft Starter, SIRIUS, 38A, 45mm","metaDescription":"Siemens 3RW3028-2BB04 SIRIUS soft starter, 38A at 40°C, 600V insulation, integrated bypass, spring terminals, size S0, 45mm wide.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Soft Starters"],"specifications":{"Depth":"150mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"45mm","title":"3RW3028-2BB04","Height":"150mm","Upwards":"60mm","Downwards":"40mm","Thyristors":"Yes","At The Side":"15mm","description":"SIRIUS soft starter S0 38 A, 18.5 kW/400 V, 40 °C 200-480 V AC, 24 V AC/DC spring-type terminals","During Storage":"-40 ... +80°C","External Reset":"No","lifecycle_stage":"current","During Operation":"-25 ... +60°C","Fastening Method":"screw and snap-on mounting","Minimum Load [%]":"10%","For Main Contacts":"16 ... 8","Mounting Position":"With vertical mounting surface +/-10° rotatable, with vertical mounting surface +/- 10° 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":"300m","Derating Temperature":"40°C","Inside-Delta Circuit":"No","at 50 Hz rated value":"24V","at 60 Hz rated value":"24V","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":"No","Intrinsic Device Protection":"No","Adjustable Current Limitation":"No","Size Of Engine Control Device":"S0","Insulation Voltage Rated Value":"600V","Using The Front Clamping Point":"1x 8, 2x (16 ... 10)","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","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":"18.5kW","at standard circuit at 50 °C rated value":"25hp","control supply voltage 1 at DC rated value":"24V","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"1","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":"200 ... 480V","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%"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/59abedfad64c01d626db98bd8465fdc1.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=469878&mlfb=3RW3028-2BB04"},"ai":{"faq":[{"question":"Where can I buy the 3RW3028-2BB04 and get a price?","answer":"Sourced to order through independent distribution. No stock-holding claim — quoted per BOM."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW3028-2BB04","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/3RW3028-2BB04 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}}