{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV2421-4DA20","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV2421-4DA20","canonicalUrl":"https://aoctrl.com/siemens/3RV2421-4DA20","factsUrl":"https://aoctrl.com/api/mcp/products/3RV2421-4DA20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS circuit breaker, 3RV2421-4DA20, for transformer protection, 45 mm wide, 25 kA breaking capacity at 400 V AC, Class 10 trip, spring-loaded terminals.","salesMarkdown":"Rated operating voltage spans 20 to 690 V. That tells you where the arc extinction is comfortable and where you need upstream current-limiting fuses. Any mounting position is allowed. Minimum clearances to adjacent metal parts: 50 mm upwards and downwards, 30 mm at the sides, zero forwards and backwards. That zero-clearance rear face means it can sit flush against a backplate — useful when packing a panel tight. ## Ratings & Coordination For transformer primary protection, the fuse coordination values are given: at 400 V, a gL/gG fuse up to 63 A; at 500 V and 690 V, up to 50 A. Motor horsepower equivalents are listed for reference: 15 hp at 460/480 V, 7.5 hp at 220/230 V, 5 hp at 200/208 V, 3 hp at 230 V, 2 hp at 110/120 V. Maximum switching frequency in AC-3 duty is 15 operations per hour. ## Terminals & Wiring Main current circuit connections use spring-loaded terminals. Accepts solid or stranded copper: 2 x 1 to 10 mm² per terminal. Strip length and torque values follow the standard SIRIUS spring-clamp spec — no special tooling needed beyond a screwdriver. ## Environmental That's a standard industrial envelope — no special climate control required for warehousing.","metaTitle":"Siemens 3RV2421-4DA20 SIRIUS Circuit Breaker, 25 kA at 400 V","metaDescription":"Siemens 3RV2421-4DA20 SIRIUS circuit breaker for transformer protection. 25 kA breaking capacity at 400 V AC, Class 10 trip, 45 mm wide. Sourced to order.","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":"3RV2421-4DA20","Height":"119 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 Spring-type 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","Mounting Position":"any","Solid Or Stranded":"2x (1 ... 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":"spring-loaded 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 3 mm","Size Of The Circuit-Breaker":"S0","Size Of The Screwdriver Tip":"3,0 x 0,5 mm","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","Design Of The Short-Circuit Trip":"magnetic","for AWG cables for main contacts":"2x (18 ... 8)","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 ... 6 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","Finely Stranded Without Core End Processing":"2x (1 ... 6 mm²)","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/ddafa820a5683b6c0b5fb31fc8389b80.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=453032&mlfb=3RV2421-4DA20"},"ai":{"faq":[{"question":"Where can I buy 3RV2421-4DA20 and how do I get a price?","answer":"The part is sourced to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm price and lead time."},{"question":"What is 3RV2421-4DA20's listed depth (97 mm) on this component line?","answer":"The listed depth is 97 mm. Width is 45 mm, height is 119 mm."},{"question":"Will 3RV2421-4DA20 drop into a panel that was specified around 3RV2023-4DA10 without rewiring?","answer":"The 3RV2421-4DA20 is a SIRIUS circuit breaker for transformer protection, while the 3RV2023-4DA10 is a different variant in the same family. Both share the same 45 mm width and DIN-rail mounting, so the footprint is the same. However, the trip characteristics and breaking capacities differ — verify the coordination study before swapping."},{"question":"What compliance documentation does this brand provide for 3RV2421-4DA20 (RoHS, REACH, UL, IEC)?","answer":"As a Siemens SIRIUS product, standard compliance documentation includes CE marking, UL/CSA recognition, and RoHS/REACH declarations. Specific certificates are available from Siemens on request."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV2421-4DA20","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/3RV2421-4DA20 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}}