{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3RV1421-4BA38-1KT0","brand":"Siemens","brandSlug":"siemens","productSlug":"3RV1421-4BA38-1KT0","canonicalUrl":"https://aoctrl.com/siemens/3RV1421-4BA38-1KT0","factsUrl":"https://aoctrl.com/api/mcp/products/3RV1421-4BA38-1KT0","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SIRIUS, circuit breaker for transformer protection, 3RV1421-4BA38-1KT0, 20 A continuous, CLASS 10 trip, 690 V rated, screw terminals, IP20 front.","salesMarkdown":"## Transformer-protection circuit breaker, 20 A, CLASS 10 Breaking capacity is substantial: 100 kA at 240 V AC, 50 kA at 400 V AC, 10 kA at 500 V AC, and 4 kA at 690 V AC. Ground fault detection is not included, so any ground-fault protection must be handled upstream. The 45 mm width (3 module spaces) and 97 mm height fit standard panel layouts. Depth is 96 mm — check your enclosure depth if you are retrofitting into a shallow gland plate or a tight back panel. Main current circuit uses screw-type terminals accepting 2x (0.25... 2.5 mm²) solid or 2x (24... 14) AWG. Auxiliary and control circuits use spring-loaded terminals on the same wire range. The auxiliary switch is transverse design and is field-installable as a product extension — order it separately if you need remote status indication. ## Auxiliary contact ratings and power dissipation The auxiliary contact block (when fitted) is rated 1 A at 24 V, 0.5 A at 230 V, and 0.15 A at 60 V. These are the switching capacities for the control circuit — sufficient for PLC inputs or relay coils, but verify your load's inrush against the 1 A maximum at 24 VDC. The part is RoHS compliant with a substance prohibition date of 01.05.2012, meaning it meets the EU RoHS directive effective from that date. The SIRIUS series typically carries UL, CSA, and CE certifications, though specific approvals for this exact order code should be verified against the nameplate. The manufacturer provides a declaration of conformity and a PDF manual; these are available through the standard Siemens documentation portal.","metaTitle":"Siemens SIRIUS 3RV1421-4BA38-1KT0 Circuit Breaker, 20 A, CLA","metaDescription":"Siemens SIRIUS 3RV1421-4BA38-1KT0 transformer-protection circuit breaker, 20 A continuous, CLASS 10 trip, 50 kA at 400 V. Current lifecycle. Sourced to order. Request RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Motor Protection Circuit Breakers (MPCB)"],"specifications":{"Depth":"96 mm","Solid":"2x (0.25 ... 2.5 mm²)","Width":"45 mm","Height":"97 mm","at 24 V":"1 A","at 60 V":"0.15 A","at 230 V":"0.5 A","Backwards":"0 mm","Trip Class":"CLASS 10","At The Side":"0 mm","Rated Value":"690 V","During Storage":"-50 ... +80 °C","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 50022","Shock Resistance":"25g / 11 ms","Mounting Position":"any","Product Brand Name":"SIRIUS","Product Designation":"circuit breaker","Design Of The Product":"for transformer protection","Ground Fault Detection":"No","Phase Failure Detection":"Yes","For Main Current Circuit":"screw-type terminals","at AC at 240 V rated value":"100 kA","at AC at 400 V rated value":"50 kA","at AC at 500 V rated value":"10 kA","at AC at 690 V rated value":"4 kA","at AC-3 rated value maximum":"690 V","at AC in hot operating state":"10.5 W","Substance Prohibitance (Date)":"01.05.2012","Continuous Current Rated Value":"20 A","Design Of The Auxiliary Switch":"transverse","at AWG cables for main contacts":"2x (24 ... 14)","protection class IP on the front":"IP20","For Auxiliary And Control Circuit":"spring-loaded terminals","Product Extension Auxiliary Switch":"Yes","operating frequency at AC-3 maximum":"15 1/h","Surge Voltage Resistance Rated Value":"6 000 V","at AWG cables for auxiliary contacts":"2x (24 ... 14)","at AC in hot operating state per pole":"3.5 W","Finely Stranded With Core End Processing":"2x (0.25 ... 1.5 mm²)","Number Of Poles For Main Current Circuit":"3","Touch Protection Against Electrical Shock":"finger-safe","Finely Stranded Without Core End Processing":"2x (0.25 ... 2.5 mm²)","number of CO contacts for auxiliary contacts":"0","operational current at AC-3 at 400 V rated value":"20 A","Installation Altitude At Height Above Sea Level Maximum":"2 000 m","Design Of The Overcurrent Release And Short-Circuit Release":"thermomagnetic","Arrangement Of Electrical Connectors For Main Current Circuit":"front side","Product Component Removable Terminal For Auxiliary And Control Circuit":"No","Mechanical Service Life (Switching Cycles) Of The Main Contacts Typical":"100 000","Adjustable Current Response Value Current Of The Current-Dependent Overload Release":"14 ... 20 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=497292&mlfb=3RV1421-4BA38-1KT0","alternativesUrl":"https://aoctrl.com/api/mcp/products/3RV1421-4BA38-1KT0/alternatives.json"},"ai":{"faq":[{"question":"What is 3RV1421-4BA38-1KT0's listed depth?","answer":"The depth is 96 mm. This is the dimension from the DIN rail mounting surface to the front of the breaker — relevant for enclosure depth clearance."},{"question":"What compliance documentation does this brand provide for 3RV1421-4BA38-1KT0?","answer":"RoHS compliance is documented with a substance prohibition date of 01.05.2012. The SIRIUS series typically also carries UL, CSA, and CE certifications. A declaration of conformity and PDF manual are available from the manufacturer."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3RV1421-4BA38-1KT0","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/3RV1421-4BA38-1KT0 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}}