{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RW4027-1BB05","brand":"Siemens","brandSlug":"siemens","productSlug":"3RW4027-1BB05","canonicalUrl":"https://aoctrl.com/siemens/3RW4027-1BB05","factsUrl":"https://aoctrl.com/api/mcp/products/3RW4027-1BB05","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS 3RW4027-1BB05 soft starter, 32 A at 40 °C, 600 V insulation voltage, size S0, integrated bypass, screw and snap-on mounting, 24 V control voltage.","salesMarkdown":"## 32 A at 40 °C — derating drives the real current limit The 3RW4027-1BB05: That 40 °C baseline is the typical unventilated panel ceiling — if your enclosure runs hotter, the usable current drops by about 10 % per 10 °C rise. The integrated bypass contact system shunts the thyristors out of the circuit once the motor reaches full speed, eliminating the heat load from the semiconductor junction during steady-state running. That means the derating curve applies only during the start cycle — continuous current after bypass is limited by the bypass contacts, not the thyristors. ## Size S0 frame — panel layout and mounting constraints The unit measures 45 mm wide by 125 mm high by 155 mm deep, fitting the S0 frame footprint common across the SIRIUS 3RW40 series. Fastening is screw and snap-on mounting — the DIN rail clip holds it in place, but the screw lug provides positive retention under vibration. Mounting position matters for the internal fan: with the additional fan fitted, the unit allows vertical mounting surface rotation of ±90° and tilt of ±22.5° front/back. Without the fan, rotation is limited to ±10° and tilt to ±10° — plan the panel layout so the soft starter sits within those limits or add the fan. Clearance requirements: 60 mm upwards, 40 mm downwards, 15 mm at the sides. These are the minimum air gaps for natural convection cooling — stacking units closer than that forces additional derating or forced airflow. ## Motor protection and control features built in Motor overload protection, intrinsic device protection, and adjustable current limitation are all integrated — no separate overload relay needed downstream. The minimum load is 20 %, so it handles lightly loaded motors without nuisance tripping. External reset allows the soft starter to be reset from a remote pushbutton or PLC output after a fault trip. The red fault signal display gives local indication of the trip cause. Maximum wire length to the motor is 300 m — for longer cable runs, reflected wave overvoltage at the motor terminals becomes a risk, especially on 600 V insulation systems. Keep the run under that limit or add an output reactor.","metaTitle":"Siemens 3RW4027-1BB05 Soft Starter SIRIUS, 32A, 600V","metaDescription":"Siemens 3RW4027-1BB05 SIRIUS soft starter, 32A at 40°C, 600V insulation, integrated bypass, active production. Quoted to order against BOM.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Soft Starters"],"specifications":{"Depth":"155mm","Solid":"2x (0.5 ... 2.5 mm²)","Width":"45mm","title":"3RW4027-1BB05","Height":"125mm","Upwards":"60mm","Downwards":"40mm","Thyristors":"Yes","At The Side":"15mm","description":"SIRIUS soft starter S0 32 A, 18.5 k kW/500 V, 40 °C 400-600 V AC, 24 V AC/DC Screw 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%","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 50 Hz rated value":"24V","at 60 Hz rated value":"24V","at 40 °C rated value":"32A","at 50 °C rated value":"29A","at 60 °C rated value":"26A","For Auxiliary Contacts":"2x (20 ... 14)","For Main Current Circuit":"screw-type 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)","Operating Frequency Rated Value":"50 ... 60Hz","Display Version For Fault Signal":"red","Integrated Bypass Contact System":"Yes","For Auxiliary And Control Circuit":"screw-type 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 (0.5 ... 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":"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%","For Auxiliary Contacts Finely Stranded With Core End Processing":"2x (20 ... 16)","relative negative tolerance of the control supply voltage at DC":"-20%","relative positive tolerance of the control supply voltage at DC":"20%","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":"13W","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":"17A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/203bc1e2f21eb86dc0b8f2607933a3d3.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=516745&mlfb=3RW4027-1BB05"},"ai":{"faq":[{"question":"How can I order the 3RW4027-1BB05 and get a price?","answer":"No stock-holding claim is made — every order is confirmed before commitment."},{"question":"What compliance documentation does Siemens provide for 3RW4027-1BB05?","answer":"The soft starter carries pollution degree 3 per IEC 60947-4-2, insulation voltage 600 V, and operating temperature range -25 to +60 °C. Storage conditions follow IEC 60721 classes 1K6, 1C2, 1S2, 1M4. Full RoHS, REACH, and UL documentation is available from Siemens on request."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RW4027-1BB05","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/3RW4027-1BB05 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}}