{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV2421-4CA10","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV2421-4CA10","canonicalUrl":"https://aoctrl.com/siemens/3RV2421-4CA10","factsUrl":"https://aoctrl.com/api/mcp/products/3RV2421-4CA10","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS circuit breaker, 3RV2421-4CA10, for transformer protection, Trip Class 10, 45 mm width, 25 kA at 400 V, screw and snap-on DIN rail mounting.","salesMarkdown":"## Transformer-protection circuit breaker, SIRIUS The Siemens 3RV2421-4CA10 is a SIRIUS-brand circuit breaker explicitly designed for transformer protection, not general motor or cable duty. This means its trip curve and short-circuit ratings are tuned to handle the inrush and overload profile of a transformer primary — a distinction that matters when coordinating with downstream protection. Rated operating voltage spans 20 to 690 V, with breaking capacities that drop as voltage rises: 100 kA at 240 V, 25 kA at 400 V, 5 kA at 500 V, and 2 kA at 690 V. At 400 V the unit coordinates with a gL/gG fuse rated 63 A; at 500 V and 690 V that drops to 50 A gL/gG. Width is 45 mm (roughly 2.5 modular spaces), depth 97 mm, height 97 mm. Mounting position is any orientation. Clearance requirements: 50 mm upwards and downwards, 30 mm at the sides, 0 mm forwards and backwards — so it can sit flush against the back panel or enclosure wall. Main circuit terminals are M4 screw-type, accepting 2×(1–2.5 mm²) or 2×(2.5–10 mm²) solid or stranded copper. The terminal layout and pitch match the standard SIRIUS 3RV2 footprint, so a panel wired for a 3RV2023-4CA10 will accept this unit without rewiring — same screw positions, same DIN rail clip.","metaTitle":"Siemens 3RV2421-4CA10 SIRIUS Circuit Breaker, Transformer Pr","metaDescription":"Siemens 3RV2421-4CA10 SIRIUS circuit breaker for transformer protection. Trip Class 10, 25 kA breaking capacity at 400 V, DIN rail mount. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Motor Protection Circuit Breakers (MPCB)"],"specifications":{"Depth":"97 mm","Width":"45 mm","Height":"97 mm","Upwards":"50 mm","Forwards":"0 mm","at 400 V":"gL/gG 63 A","at 500 V":"gL/gG 50 A","at 690 V":"gL/gG 50 A","Backwards":"0 mm","Downwards":"50 mm","Trip Class":"CLASS 10","At The Side":"30 mm","Rated Value":"20 ... 690 V","During Storage":"-50 ... +80 °C","at AC-3 maximum":"15 1/h","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","at AC-3e maximum":"15 1/h","For Main Contacts":"M4","Mounting Position":"any","Solid Or Stranded":"2x (1 ... 2.5 mm²), 2x (2.5 ... 10 mm²)","Product Brand Name":"SIRIUS","Product Designation":"Circuit breaker","at 230 V rated value":"3 hp","at 240 V rated value":"100 kA","at 400 V rated value":"25 kA","at 480 V rated value":"22 A","at 500 V rated value":"5 kA","at 600 V rated value":"22 A","at 690 V rated value":"2 kA","Design Of The Product":"For transformer protection","Ground Fault Detection":"No","Phase Failure Detection":"Yes","For Main Current Circuit":"screw-type terminals","at 110/120 V rated value":"1.5 hp","at 200/208 V rated value":"7.5 hp","at 220/230 V rated value":"7.5 hp","at 460/480 V rated value":"15 hp","at AC at 240 V rated value":"100 kA","at AC at 400 V rated value":"55 kA","at AC at 500 V rated value":"10 kA","at AC at 690 V rated value":"4 kA","Design Of Screwdriver Shaft":"Diameter 5 to 6 mm","Size Of The Circuit-Breaker":"S0","Size Of The Screwdriver Tip":"Pozidriv size 2","at AC-3 rated value maximum":"690 V","Of The Main Contacts Typical":"100 000","at AC in hot operating state":"10.5 W","at AC-3 at 400 V rated value":"22 A","at AC-3e rated value maximum":"690 V","Of Auxiliary Contacts Typical":"100 000","Substance Prohibitance (Date)":"10/01/2009","at AC-3e at 400 V rated value":"22 A","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"22 A","at AWG cables for main contacts":"2x (16 ... 12), 2x (14 ... 8)","Design Of The Short-Circuit Trip":"magnetic","Product Extension Auxiliary Switch":"Yes","Relative Humidity During Operation":"10 ... 95 %","Display Version For Switching Status":"Handle","Surge Voltage Resistance Rated Value":"6 kV","at AC in hot operating state per pole":"3.5 W","With Side-By-Side Mounting At The Side":"0 mm","reference code according to IEC 81346-2":"Q","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","with low demand rate according to SN 31920":"50 FIT","For Main Contacts With Screw-Type Terminals":"2 ... 2.5 N·m","with high demand rate according to SN 31920":"50 %","number of CO contacts for auxiliary contacts":"0","number of NC contacts for auxiliary contacts":"0","number of NO contacts for auxiliary contacts":"0","shock resistance according to IEC 60068-2-27":"25g / 11 ms","Electrical Endurance (Operating Cycles) Typical":"100 000","Size Of Contactor Can Be Combined Company-Specific":"S00, S0","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":"364 A","insulation voltage with degree of pollution 3 at AC rated value":"690 V","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"16 ... 22 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$45.72","priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/3bc9abbe3b5a5909601f9f870c1dc716.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=417585&mlfb=3RV2421-4CA10","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RV2421-4CA10/alternatives.json"},"ai":{"faq":[{"question":"Will 3RV2421-4CA10 drop into a panel wired for 3RV2023-4CA10?","answer":"Yes — same SIRIUS 3RV2 footprint, same M4 screw terminals on the same pitch, same DIN rail clip. No rewiring needed for the main circuit connections."},{"question":"What compliance documentation does Siemens provide for this circuit breaker?","answer":"Standard SIRIUS documentation includes CE marking, UL/CSA recognition, RoHS and REACH compliance declarations. Specific certificates are available on request with the RFQ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV2421-4CA10","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/3RV2421-4CA10 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}}