{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV2421-1FA10","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV2421-1FA10","canonicalUrl":"https://aoctrl.com/siemens/3RV2421-1FA10","factsUrl":"https://aoctrl.com/api/mcp/products/3RV2421-1FA10","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS circuit breaker, 3RV2421-1FA10, for transformer protection, Trip Class 10, 100 kA breaking capacity at 400 V, screw and snap-on mounting onto 35 mm DIN rail.","salesMarkdown":"The Siemens 3RV2421-1FA10 is a SIRIUS-brand circuit breaker explicitly designed for transformer protection — not a general-purpose motor protective breaker, but one whose trip curve and breaking capacity are matched to the inrush and fault characteristics of a transformer primary. That distinction matters when you're coordinating a panel: a standard motor-protective breaker might nuisance-trip on transformer magnetizing inrush, whereas this unit's design accounts for that transient. The fuse coordination values are given as gL/gG 32 A at 400 V and 500 V, stepping down to 25 A at 690 V; these are the maximum upstream fuse ratings that preserve selectivity. The 45 mm width occupies two 22.5 mm module spaces on the DIN rail, so plan your rail layout accordingly. Depth is 97 mm, height 97 mm; the unit sits flush with no forward projection beyond the front face (: 0 mm forwards). Clearance requirements: 50 mm upwards, 50 mm downwards, 30 mm at the side — these are the minimum free air gaps for arc venting and heat dissipation. The main contacts use M4 screw terminals, accepting 2×(1–2.5 mm²) solid or stranded, or 2×(2.5–10 mm²) — typical for a transformer primary feed up to around 7.5 kVA at 400 V. Maximum switching frequency in AC-3 duty is 15 operations per hour, which is adequate for transformer switching but not for frequent motor starting cycles.","metaTitle":"Siemens 3RV2421-1FA10 SIRIUS Circuit Breaker, Transformer Pr","metaDescription":"Siemens 3RV2421-1FA10 SIRIUS circuit breaker for transformer protection. 100 kA breaking capacity at 400 V, Trip Class 10, screw and snap-on DIN rail mount. Sourced to order agains","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":"3RV2421-1FA10","Height":"97 mm","Upwards":"50 mm","Forwards":"0 mm","at 400 V":"gL/gG 32 A","at 500 V":"gL/gG 32 A","at 690 V":"gL/gG 25 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 3.5...5 A Short-circuit release 104 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 standard mounting 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":"0.5 hp","at 240 V rated value":"100 kA","at 400 V rated value":"100 kA","at 480 V rated value":"5 A","at 500 V rated value":"100 kA","at 600 V rated value":"5 A","at 690 V rated value":"4 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":"0.17 hp","at 200/208 V rated value":"1 hp","at 220/230 V rated value":"1 hp","at 460/480 V rated value":"3 hp","at 575/600 V rated value":"3 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":"6 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":"5 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":"5 A","Design Of The Overload Release":"thermal","Operating Frequency Rated Value":"50 ... 60 Hz","Operational Current Rated Value":"5 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 (Switching 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":"104 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":"3.5 ... 5 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/2110faf4dd38b0ba146c6efc2619b555.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1135055&mlfb=3RV2421-1FA10"},"ai":{"faq":[{"question":"What is the breaking capacity of 3RV2421-1FA10 at 400 V?","answer":"The breaking capacity is 100 kA at 400 V, also 100 kA at 500 V, and 4 kA at 690 V."},{"question":"What are the mounting dimensions and clearances for 3RV2421-1FA10?","answer":"Width is 45 mm, depth 97 mm, height 97 mm. Required clearances: 50 mm upwards, 50 mm downwards, 30 mm at the side. Mounts on 35 mm DIN rail per DIN EN 60715."},{"question":"Where can I buy 3RV2421-1FA10 and how is it quoted?","answer":"The 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":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV2421-1FA10","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/3RV2421-1FA10 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}}