{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"4EU4321-8AA00-0A","brand":"Siemens","brandSlug":"siemens","productSlug":"4EU4321-8AA00-0A","canonicalUrl":"https://aoctrl.com/siemens/4EU4321-8AA00-0A","factsUrl":"https://aoctrl.com/api/mcp/products/4EU4321-8AA00-0A","rawCanonicalId":null},"summary":{"shortDescription":"Siemens 4EU4321-8AA00-0A commutating choke for converters, 3-phase, 690V AC, 630A max / 567A rated, 0.076 mH, IP00, flat-type terminals.","salesMarkdown":"The Siemens 4EU4321-8AA00-0A is a three-phase commutating choke designed for converter applications. It carries a maximum current of 630 A at 50 Hz and a rated continuous current of 567 A, with an operating voltage of 690 V AC. The rated inductance is 0.076 mH, and the relative inductive voltage drop is 4% at rated current and frequency. These ratings define the choke's ability to limit di/dt and smooth commutation notches in the DC link of a line-commutated converter — a critical role in protecting the thyristors or IGBTs from excessive turn-on stress and reducing harmonic injection back onto the supply. That means the choke can carry 567 A indefinitely without exceeding its insulation temperature limit — a key number for sizing the DC-link bus. The 630 A maximum (I thmax) is a short-time thermal limit at 50 Hz, not a continuous rating. The 772 A DC rated value tells you the choke can handle a DC bias current of 772 A when used in a DC-link application, which is higher than the AC rating because the RMS current in the DC link is lower for the same copper loss. The 4% voltage drop is the impedance at rated current — it sets the commutation notch attenuation and determines whether the converter's control loop sees enough voltage margin. The 480 W coil loss plus 325 W iron core loss (805 W total at rated conditions) must be dissipated in the enclosure; IP00 means the choke is open-frame and relies on the cabinet's forced-air or natural convection — no integral fan. ## Integration and physical fit The choke measures 0.46 m wide by 0.435 m high by 0.265 m deep — a substantial footprint that needs to be accounted for in the cabinet layout. The main current circuit connects via flat-type terminals (busbar or flat-cable lugs), not screw clamps or spring cages. No DIN-rail mounting; this is a bolt-down component. The open-frame IP00 construction means it must be installed inside a suitable enclosure with proper clearance to grounded metalwork and adequate ventilation for the 805 W total loss.","metaTitle":"Siemens 4EU4321-8AA00-0A Commutating Choke, 630A, 690V, 3-Ph","metaDescription":"Siemens 4EU4321-8AA00-0A commutating choke for converters. 630A max, 567A rated, 690V AC, 3-phase. IP00, flat connectors. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Line/Load Reactors"],"specifications":{"Depth":"0.265m","Width":"0.46m","Height":"0.435m","Maximum":"630A","Rated Value":"567A","Phase number":"3","Type of voltage":"AC","lifecycle_stage":"mature","at DC rated value":"772A","Product designation":"Kommut.-Drossel f. Stromrichter","Protection class IP":"IP00","Inductivity rated value":"0.000076H","Power loss [W] of the coil":"480W","Operating voltage rated value":"690V","Ambient temperature rated value":"40°C","Operating frequency rated value":"50Hz","Power loss [W] of the iron core":"325W","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=417706&mlfb=4EU4321-8AA00-0A","alternativesUrl":"https://aoctrl.com/api/mcp/products/4EU4321-8AA00-0A/alternatives.json"},"ai":{"faq":[{"question":"What is the rated current of this choke?","answer":"The rated continuous current is 567 A at 40 °C ambient, with a maximum short-time rating of 630 A at 50 Hz. The DC rated value is 772 A."},{"question":"What is the voltage drop across the choke?","answer":"The relative inductive voltage drop is 4% at rated current, voltage, and frequency."},{"question":"Where can I buy 4EU4321-8AA00-0A?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/4EU4321-8AA00-0A","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/4EU4321-8AA00-0A 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}}