{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RA1444-8XB20-1BB4","brand":"Siemens","brandSlug":"siemens","productSlug":"3RA1444-8XB20-1BB4","canonicalUrl":"https://aoctrl.com/siemens/3RA1444-8XB20-1BB4","factsUrl":"https://aoctrl.com/api/mcp/products/3RA1444-8XB20-1BB4","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS wye-delta contactor assembly 3RA1444-8XB20-1BB4, 3-pole, 115 A AC-3 at 400 V, 55 kW motor rating, 24 V DC coil, screw terminals, IP20 front protection.","salesMarkdown":"The Siemens 3RA1444-8XB20-1BB4 is a SIRIUS wye-delta contactor assembly — a pre-configured set of three contactors (sizes S3, S3, S2) in a single enclosure, designed to reduce inrush current during motor starting. That translates to a 55 kW motor at 400 V, 81 kW at 500 V, and 93 kW at 690 V — the voltage-dependent power curve tells you exactly which motor frame it fits on your line. The assembly ships without a surge suppressor — you'll need to add a free-wheeling diode or RC snubber across the coil if your PLC output card doesn't include one. Mounting is screw fixing onto a vertical surface, with ±180° rotation and ±30° tilt front-to-back — enough flexibility to fit into tight panel layouts. Operating temperature range is -25 to +60 °C, storage -55 to +80 °C, and pollution degree 3 means it's rated for industrial environments with conductive pollution. The assembly measures 218 mm wide, 207 mm deep, and 180 mm tall. That's a compact footprint for a three-contactor wye-delta set — it fits on a standard backplate without needing a separate enclosure for each contactor. Main circuit connections are screw-type terminals, sized for the 115 A AC-3 rating. The assembly has 3 poles for the main current circuit and no NC contacts on the main poles — the switching sequence is handled internally by the wye-delta logic. The assembly includes an auxiliary switch extension option (Product Extension Auxiliary Switch: Yes), so you can add feedback contacts for status monitoring without modifying the main contactor block.","metaTitle":"Siemens 3RA1444-8XB20-1BB4 SIRIUS Star-Delta Contactor","metaDescription":"Siemens 3RA1444-8XB20-1BB4 SIRIUS wye-delta contactor assembly. Rated 115 A AC-3 at 400 V, 55 kW. 24 V DC coil, IP20 front, screw terminals.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Starters"],"specifications":{"Depth":"207 mm","Width":"218 mm","Height":"180 mm","at 50 Hz":"0.8 ... 1.1","at 60 Hz":"0.85 ... 1.1","At The Side":"0 mm","Initial Value":"0.8","During Storage":"-55 ... +80 °C","Leading Contact":"0","lifecycle_stage":"current","During Operation":"-25 ... +60 °C","During Transport":"-55 ... +80 °C","Fastening Method":"screw fixing","Full-Scale Value":"1.1","Product Function":"wye-delta-contactor","Mounting Position":"with vertical mounting surface +/-180° rotatable, with vertical mounting surface +/- 30° tiltable to the front and back","Size Of Contactor":"S3, S3, S2","at DC rated value":"24 V","Product Brand Name":"SIRIUS","Degree Of Pollution":"3","Product Designation":"contactor assembly","at 400 V rated value":"55 kW","at 500 V rated value":"81 kW","at 690 V rated value":"93 kW","at AC-3 at 400 V rated value":"115 A","Substance Prohibitance (Date)":"05/01/2012","Design Of The Surge Suppressor":"without","For Grounded Parts At The Side":"0 mm","protection class IP on the front":"IP20","Product Extension Auxiliary Switch":"Yes","With Type Of Assignment 2 Required":"fuse gL/gG: 125 A","With Type Of Coordination 1 Required":"fuse gL/gG: 250 A","With Side-By-Side Mounting At The Side":"0 mm","number of NC contacts for main contacts":"0","reference code according to IEC 81346-2":"Q","Number Of Poles For Main Current Circuit":"3","Contact Reliability Of Auxiliary Contacts":"1 faulty switching per 100 million (17 V, 1 mA)","Type Of Voltage Of The Control Supply Voltage":"DC","operating voltage at AC-3 rated value maximum":"690 V","Type Of Electrical Connection For Main Current Circuit":"screw-type terminals","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","number of NC contacts for auxiliary contacts lagging switching":"0","insulation voltage with degree of pollution 3 at AC rated value":"690 V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=183337&mlfb=3RA1444-8XB20-1BB4","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RA1444-8XB20-1BB4/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RA1444-8XB20-1BB4","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/3RA1444-8XB20-1BB4 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}