{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV2421-0KA10","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV2421-0KA10","canonicalUrl":"https://aoctrl.com/siemens/3RV2421-0KA10","factsUrl":"https://aoctrl.com/api/mcp/products/3RV2421-0KA10","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS circuit breaker, 3RV2421-0KA10, for transformer protection, 100 kA breaking capacity at 400 V AC, Class 10 trip, screw and snap-on 35 mm DIN rail mounting.","salesMarkdown":"## What this SIRIUS breaker does That's fast enough to protect the transformer winding from sustained overload, but slow enough to ride through the magnetizing inrush pulse on energization. Rated breaking capacity hits 100 kA at 240 V AC and 400 V AC, and holds that same 100 kA at 500 V AC and 690 V AC. That is a flat SCCR curve across the common industrial voltages — you get full fault-clearing ability without derating the interrupting rating at higher line voltages. Mounting position is any orientation, so it works in horizontal or vertical DIN-rail layouts. Clearance requirements: 50 mm above and below, 30 mm to the side, zero forward or backward. Main circuit terminals accept screw-type connections, with solid or stranded wire: 2× (1 to 2.5 mm²) or 2× (2.5 to 10 mm²). Main contact screws are M4.","metaTitle":"Siemens 3RV2421-0KA10 SIRIUS Circuit Breaker, Transformer Pr","metaDescription":"Siemens 3RV2421-0KA10 SIRIUS circuit breaker for transformer protection. 100 kA breaking capacity at 400 V AC, Class 10 trip, screw/snap-on DIN rail mount. 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":"3RV2421-0KA10","Height":"97 mm","Upwards":"50 mm","Forwards":"0 mm","at 500 V":"gL/gG 16 A","at 690 V":"gL/gG 16 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 0.9...1.25 A Short-circuit release 26 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":"0.2 kW","at 240 V rated value":"100 kA","at 400 V rated value":"100 kA","at 480 V rated value":"1.25 A","at 500 V rated value":"100 kA","at 600 V rated value":"1.25 A","at 690 V rated value":"100 kA","Design Of The Product":"For transformer protection","Ground Fault Detection":"No","Phase Failure Detection":"Yes","For Main Current Circuit":"screw-type terminals","at 460/480 V rated value":"1 hp","at 575/600 V rated value":"0.5 hp","at AC at 240 V rated value":"100 kA","at AC at 400 V rated value":"100 kA","at AC at 500 V rated value":"100 kA","at AC at 690 V rated value":"100 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":"5.5 W","at AC-3 at 400 V rated value":"1.25 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":"1.25 A","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"1.25 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":"1.8 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":"26 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":"0.9 ... 1.25 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/41028b05965751db8fd8c5ddae347cca.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1135049&mlfb=3RV2421-0KA10"},"ai":{"faq":[{"question":"What is the breaking capacity of the 3RV2421-0KA10 at 400 V?","answer":"The 3RV2421-0KA10 is rated for 100 kA breaking capacity at 400 V AC."},{"question":"Will the 3RV2421-0KA10 drop into a panel wired for the 3RV2011-0AA10?","answer":"Both are 45 mm-wide SIRIUS breakers on the same 35 mm DIN-rail footprint, so the mechanical fit is the same. Verify the trip class and transformer protection curve match your load — the 3RV2421-0KA10 is Class 10 and designed for transformer protection, which differs from the standard motor-protection characteristic of the 3RV2011-0AA10."},{"question":"Where can I buy the 3RV2421-0KA10 and how is it quoted?","answer":"The 3RV2421-0KA10 is sourced to order through independent distribution. Submit an RFQ for availability and current pricing — quotes are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV2421-0KA10","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/3RV2421-0KA10 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}}