{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV6421-4BA10","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV6421-4BA10","canonicalUrl":"https://aoctrl.com/siemens/3RV6421-4BA10","factsUrl":"https://aoctrl.com/api/mcp/products/3RV6421-4BA10","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS circuit breaker 3RV6421-4BA10, size S0, 3-pole, for transformer protection, 20 A rated operational current, Class 10 trip, 690 V, screw terminals, DIN rail mount.","salesMarkdown":"The Siemens 3RV6421-4BA10 is a SIRIUS circuit breaker specifically designed for transformer protection. It combines a thermal overload release (Class 10 trip) with a magnetic short-circuit trip in a single 3-pole device, size S0. Rated operational current is 20 A at AC-3 duty on 400 V, with a maximum rated voltage of 690 V at 50/60 Hz. Any mounting position is permitted. Clearance requirements: 50 mm above and below, 30 mm to the side, 0 mm forward and backward — useful when packing multiple breakers in a panel. ## Key ratings in context Power loss is 8 W typical — a figure to factor into panel thermal budgeting when grouping several breakers in a confined enclosure. Screw-type terminals accept 2×(1–2.5 mm²) solid/stranded or 2×(2.5–10 mm²) solid, with tightening torque 2–2.5 N·m. AWG equivalents: 2×(16–12) or 2×(14–8). Top and bottom entry for main circuit connections. Rated surge voltage resistance is 6 kV; shock resistance 25 g / 11 ms per IEC 60068-2-27. Maximum installation altitude 2000 m. Substance prohibitance date 05/01/2012 indicates RoHS compliance from that date forward.","metaTitle":"Siemens 3RV6421-4BA10 SIRIUS Circuit Breaker, 20 A, Class 10","metaDescription":"Siemens 3RV6421-4BA10 SIRIUS circuit breaker for transformer protection. 20 A rated, Class 10 trip, 690 V, 50/60 Hz, DIN rail mount. Active production. Available to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Protection Circuit Breakers (MPCB)"],"specifications":{"Depth":"96 mm","Width":"45 mm","Height":"97 mm","Upwards":"50 mm","Forwards":"0 mm","Backwards":"0 mm","Downwards":"50 mm","Trip Class":"CLASS 10","At The Side":"30 mm","Rated Value":"690 V","lifecycle_stage":"current","During Operation":"-20 ... +60 °C","During Transport":"-50 ... +80 °C","Fastening Method":"screw and snap-on mounting onto 35 mm DIN rail according to DIN EN 60715","Mounting Position":"any","Solid Or Stranded":"2x (1 ... 2.5 mm²), 2x (2.5 ... 10 mm²)","Product Brand Name":"SIRIUS","Product Designation":"Circuit breaker","Design Of The Product":"for transformer protection","For Main Current Circuit":"screw-type terminals","Size Of The Circuit-Breaker":"S0","at AC-3 rated value maximum":"690 V","power loss [W] total typical":"8 W","Substance Prohibitance (Date)":"05/01/2012","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"20 A","at AWG cables for main contacts":"2x (16 ... 12), 2x (14 ... 8)","Design Of The Short-Circuit Trip":"magnetic","Relative Humidity During Operation":"10 ... 95 %","operating frequency at AC-3 maximum":"15 1/h","Surge Voltage Resistance Rated Value":"6 kV","Finely Stranded With Core End Processing":"2x (1 ... 2.5 mm²), 2x (2.5 ... 6 mm²), 1x 10 mm²","Number Of Poles For Main Current Circuit":"3","Product Function Short Circuit Protection":"Yes","For Main Contacts With Screw-Type Terminals":"2 ... 2.5 N·m","shock resistance according to IEC 60068-2-27":"25g / 11 ms","operational current at AC-3 at 400 V rated value":"20 A","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Arrangement Of Electrical Connectors For Main Current Circuit":"Top and bottom","Response Value Current Of Instantaneous Short-Circuit Trip Unit":"325 A","insulation voltage with degree of pollution 3 at AC rated value":"690 V","maximum short-circuit current breaking capacity (Icu) at AC at 400 V rated value":"55 kA","operating short-circuit current breaking capacity (Ics) at AC at 400 V rated value":"25 kA","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"13 ... 20 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/ef60885dc15db9e54997b3160f2e6abc.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=621343&mlfb=3RV6421-4BA10","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RV6421-4BA10/alternatives.json"},"ai":{"faq":[{"question":"What is 3RV6421-4BA10 used for?","answer":"It is a circuit breaker designed for transformer protection, combining thermal overload and magnetic short-circuit release in a single device. It is part of the Siemens SIRIUS family, size S0, 3-pole, rated 20 A at AC-3."},{"question":"What are the mounting clearances for 3RV6421-4BA10?","answer":"Requires 50 mm clearance above and below, 30 mm to the sides, 0 mm forward and backward. It mounts on 35 mm DIN rail per DIN EN 60715, screw and snap-on, any position."},{"question":"Where can I buy 3RV6421-4BA10?","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/3RV6421-4BA10","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/3RV6421-4BA10 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}}