{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"4EU3921-4AA00-0A","brand":"Siemens","brandSlug":"siemens","productSlug":"4EU3921-4AA00-0A","canonicalUrl":"https://aoctrl.com/siemens/4EU3921-4AA00-0A","factsUrl":"https://aoctrl.com/api/mcp/products/4EU3921-4AA00-0A","rawCanonicalId":null},"summary":{"shortDescription":"Siemens 4EU3921-4AA00-0A commutating choke for converter, 3-phase, 500V AC, 800A max / 720A rated, 43 µH, IP00, flat-type terminals.","salesMarkdown":"It handles a maximum continuous current of 800 A and a rated (nominal) current of 720 A, with a DC-side rating of 980.3 A. The inductance is 43 µH, producing a relative inductive voltage drop of 4 % at rated current and frequency. This choke sits between the AC line and the converter DC link to limit di/dt and reduce harmonic distortion — essential for protecting the converter's input rectifier and smoothing the DC bus. The 800 A maximum and 720 A rated current define the thermal limit under continuous AC operation. The DC rating of 980.3 A is higher because DC current produces lower core losses — this matters if you're using the choke on the DC side of a converter. The 4 % voltage drop at rated current is the impedance figure that determines how much the choke limits inrush and fault current; a 4 % drop is typical for a commutating choke in a 500 V system. The 43 µH inductance is the actual value that governs the rate of current rise (di/dt) — critical for matching to the converter's switching frequency and gate-drive timing. The IP00 enclosure means it's open-frame, intended for installation inside a cabinet or enclosure that provides its own protection against dust and contact. ## Thermal and connection details Total power loss is 631 W — 370 W in the coil and 261 W in the iron core. Thermal class H (IEC 60085) means the insulation system can withstand 180 °C hot-spot temperature, giving generous headroom for the 40 °C ambient rating. The main circuit connects via flat-type terminals (bus-bar style), not screw clamps — expect to bolt copper bars directly. Dimensions are 0.229 m deep, 0.41 m wide, and 0.385 m high; plan cabinet space accordingly.","metaTitle":"Siemens 4EU3921-4AA00-0A Commutating Choke, 800A, 500V AC","metaDescription":"Siemens 4EU3921-4AA00-0A commutating choke for converter, 3-phase, 500V AC, 800A max, 720A rated, 43 µH, IP00, flat terminals. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Line/Load Reactors"],"specifications":{"Depth":"0.229m","Width":"0.41m","Height":"0.385m","Maximum":"800A","Rated Value":"720A","Phase number":"3","Type of voltage":"AC","lifecycle_stage":"mature","at DC rated value":"980.3A","Product designation":"Kommut.-Drossel f. Stromrichter","Protection class IP":"IP00","Inductivity rated value":"0.000043H","Power loss [W] of the coil":"370W","Operating voltage rated value":"500, 500V","Ambient temperature rated value":"40°C","Operating frequency rated value":"60 ... 50Hz","Power loss [W] of the iron core":"261W","Thermal class acc. to IEC 60085":"H","Type of electrical connection for main current circuit":"flat connector","Relative inductive drop in voltage on the measurement level current, voltage and frequency":"4%"}},"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=277235&mlfb=4EU3921-4AA00-0A","alternativesUrl":"https://aoctrl.com/api/mcp/products/4EU3921-4AA00-0A/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/4EU3921-4AA00-0A","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/4EU3921-4AA00-0A 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}}