{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SJ6420-6","brand":"Siemens","brandSlug":"siemens","productSlug":"5SJ6420-6","canonicalUrl":"https://aoctrl.com/siemens/5SJ6420-6","factsUrl":"https://aoctrl.com/api/mcp/products/5SJ6420-6","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SJ6 series, miniature circuit breaker, 4-pole, B characteristic, 20 A rated current, 6 kA breaking capacity, 400 V AC, 70 mm installation depth.","salesMarkdown":"## What this 4-pole B-curve 20 A MCB covers ## Panel fit and wiring constraints Four poles means four width units on the DIN rail — 70 mm deep, same as the rest of the 5SJ6 family. Terminals accept solid or stranded copper from 0.75 mm² up to 25 mm², which covers most branch-circuit wiring from 1.5 mm² lighting circuits up to 6 mm² or 10 mm² feeders. Rated for ambient temperatures from -20 °C to +45 °C, with periodic excursions to +55 °C at up to 95% humidity. Storage range is wider at -40 °C to +75 °C. The mechanical endurance is 20 000 switching cycles typical. Vibration resistance is tested to IEC 60068-2-6 at 50 m/s² from 25 to 150 Hz and 60 m/s² from 10 to 150 Hz — enough for panel-mounted use in industrial machinery but not for direct mounting on a high-vibration engine block. ## DC rating and insulation coordination The DC side is rated for 60 V maximum — useful for 48 V DC control circuits or battery-backed loads, but not for higher-voltage DC strings. Insulation voltage is 440 V AC, overvoltage category III, which is typical for fixed-installation distribution boards downstream of the main panel. Energy limiting class 3 means it restricts let-through energy in a fault, aiding downstream device protection.","metaTitle":"Siemens 5SJ6420-6 SENTRON MCB, 4-Pole B 20A, 6kA","metaDescription":"Siemens 5SJ6420-6 SENTRON miniature circuit breaker, 4-pole, B-curve, 20 A, 6 kA breaking capacity per EN 60898 / IEC 60947-2. 400 V AC, 70 mm depth. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Miniature Circuit Breakers (MCB)"],"specifications":{"Solid":"0.75 ... 25 mm²","Sealable":"Yes","Stranded":"0.75 ... 25 mm²","Rated Value":"50 Hz","Halogen-Free":"Yes","Silicon-Free":"Yes","During Storage":"-40 ... +75 °C","Number of poles":"4","Type of voltage":"AC/DC","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Ambient temperature":"-20 ... +45 °C","Product designation":"Miniature circuit breakers","Protection class IP":"IP20, with connected conductors","Overvoltage category":"3","Design of the product":"Miniature circuit breaker 5SJ6","Energy limiting class":"3","Number of width units":"4","Number of poles / Note":"4","circuit-breaker / Design":"5SJ6","Current / at AC / rated value":"20 A","Tripping characteristic class":"B","at DC / rated value / maximum":"60 V","acc. to EN 60898 / rated value":"6 kA","Position / of power supply cord":"Any","acc. to IEC 60947-2 / rated value":"6 kA","Product feature / Touch protection":"Yes","Supply voltage / at AC / rated value":"400 V","Influence of the surrounding temperature":"Periodically +55°C, max. 95% humidity","Insulation voltage / at AC / rated value":"440 V","Vibration resistance / acc. to IEC 60068-2-6":"50m/s² at 25 to 150Hz and 60m/s² at 10 to 150 Hz","with multi-phase operation / at AC / maximum":"440 V","Mechanical service life (switching cycles) / typical":"20 000"}},"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=391361&mlfb=5SJ6420-6","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SJ6420-6/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of 5SJ6420-6?","answer":"6 kA per both EN 60898 and IEC 60947-2 at 400 V AC, which covers standard residential and light commercial fault levels."},{"question":"What wire sizes does 5SJ6420-6 accept?","answer":"Solid or stranded copper from 0.75 mm² up to 25 mm², covering branch circuits from 1.5 mm² lighting up to 10 mm² feeders."},{"question":"Will 5SJ6420-6 drop into a panel specified for 5SJ6220-6?","answer":"The 5SJ6220-6 is a 2-pole version; the 5SJ6420-6 is 4-pole and occupies 4 width units instead of 2. Same 70 mm depth, same terminal range, same B-curve and 20 A rating per pole — but the panel must have space for the extra two poles and the neutral/phase routing."},{"question":"Where can I buy 5SJ6420-6?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution channels. Availability and current pricing are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SJ6420-6","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/5SJ6420-6 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}}