{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV2421-4DA10","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV2421-4DA10","canonicalUrl":"https://aoctrl.com/siemens/3RV2421-4DA10","factsUrl":"https://aoctrl.com/api/mcp/products/3RV2421-4DA10","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS circuit breaker, 3RV2421-4DA10, for transformer protection, 25 kA breaking capacity at 400 V AC, Class 10, phase failure detection, screw and snap-on 35 mm DIN rail mounting.","salesMarkdown":"## Transformer-protection circuit breaker, SIRIUS series The Siemens 3RV2421-4DA10 is a SIRIUS-branded circuit breaker specifically designed for transformer protection, not general motor or feeder duty. At 240 V the interrupting rating rises to 100 kA, reflecting the higher available fault current typical in North American 240 V distribution. Depth is 97 mm; forwards clearance is 0 mm. Screw-type terminals on the main current circuit accept 2×(1…2.5 mm²) or 2×(2.5…10 mm²) solid or stranded copper — sized for transformer primary wiring up to about 10 mm². Rated ultimate short-circuit breaking capacity varies by voltage: 100 kA at 240 V, 25 kA at 400 V, 5 kA at 500 V, and 2 kA at 690 V. The 25 kA at 400 V is the figure most relevant for European 400 V three-phase panels; the 2 kA at 690 V means it is not intended for 690 V industrial mains without upstream current-limiting fuses. Back-up fuse recommendations are listed: gL/gG 63 A at 400 V, 50 A at 500 V and 690 V.","metaTitle":"Siemens 3RV2421-4DA10 SIRIUS Circuit Breaker, 25 kA at 400 V","metaDescription":"Siemens SIRIUS 3RV2421-4DA10 circuit breaker for transformer protection. 25 kA breaking capacity at 400 V AC, Class 10 trip, phase failure detection. Current lifecycle stage. Sourc","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","title":"3RV2421-4DA10","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","description":"Circuit breaker size S0 for transformer protection A-release 18...25 A N-release 400 A screw terminal Standard switching capacity","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":"25 A","at 500 V rated value":"5 kA","at 600 V rated value":"25 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":"2 hp","at 200/208 V rated value":"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":"25 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":"25 A","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"25 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":"400 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":"18 ... 25 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$52.07","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/c7af396ab7a905d9733a60104b5a0398.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=409612&mlfb=3RV2421-4DA10"},"ai":{"faq":[{"question":"Does the 3RV2421-4DA10 detect phase failure?","answer":"Yes, phase failure detection is built in. The breaker will open on a lost phase to prevent single-phase transformer heating."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV2421-4DA10","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/3RV2421-4DA10 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}