{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SN6420-8CP","brand":"Siemens","brandSlug":"siemens","productSlug":"5SN6420-8CP","canonicalUrl":"https://aoctrl.com/siemens/5SN6420-8CP","factsUrl":"https://aoctrl.com/api/mcp/products/5SN6420-8CP","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SN series, 4-pole miniature circuit breaker, 400 V AC, 50 Hz, 6 kA (EN 60898) / 15 kA (IEC 60947-2), 72 mm width, 4 MWU.","salesMarkdown":"## Siemens 5SN6420-8CP — 4-Pole MCB for 400 V Distribution The Siemens 5SN6420-8CP is a 4-pole miniature circuit breaker from the SENTRON 5SN family, rated for 400 V AC at 50 Hz. Two breaking-capacity figures matter for coordination studies. For a panel fed by a 630 kVA transformer with a prospective short-circuit current around 12 kA, the 15 kA rating keeps selectivity intact without cascading to upstream devices. The 4-pole design switches all three phases and neutral simultaneously, which avoids single-phasing on three-phase motor loads. Snap-on mounting to standard 35 mm DIN rail. Depth of 76 mm and height of 90 mm match the SENTRON 5SN family envelope; the 72 mm width (4 MWU) means it occupies four adjacent 18 mm module positions. Terminals accept solid conductors up to 35 mm² — sufficient for the outgoing feeder on a 40 A to 63 A three-phase circuit. ## DC Rating and Multi-Phase Operation The DC-side rating goes up to 72 V maximum, which suits control-circuit protection in DC bus applications within that voltage ceiling. For AC multi-phase operation the maximum operating voltage is 440 V — the same for single-phase and multi-phase connections, so the breaker can be used on a 400/440 V three-phase system or on a single 277 V line-to-neutral leg. Power loss per pole at rated current in hot state is 1.6 W; for a 4-pole breaker that totals 6.4 W dissipated inside the enclosure, worth factoring into thermal calculations for a densely populated panel.","metaTitle":"Siemens 5SN6420-8CP SENTRON MCB, 4-Pole, 400V, 6kA/15kA","metaDescription":"Siemens 5SN6420-8CP SENTRON 4-pole MCB, 400V AC, 50 Hz, 6 kA per EN 60898, 15 kA per IEC 60947-2. 72 mm wide, 4 MWU. Active production, quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["4-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Width":"72 mm","title":"5SN6420-8CP","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","description":"MCB 5SN","Number Of Poles":"4","lifecycle_stage":"current","Installation Depth":"70 mm","at DC rated value maximum":"72 V","Number Of Modular Width Units":"4","supply voltage at AC rated value":"400 V","according to EN 60898 rated value":"6 kA","Supply Voltage Frequency Rated Value":"50 Hz","according to IEC 60947-2 rated value":"15 kA","with multi-phase operation at AC maximum":"440 V","with multi-phase operation at AC rated value":"440 V","with single-phase operation at AC rated value":"440 V","Connectable Conductor Cross-Section Solid Maximum":"35 mm²","Mechanical Service Life (Operating Cycles) Typical":"10 000","power loss [W] for rated value of the current at AC in hot operating state per pole":"1.6 W"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/9a962e34e10c45fe54cd70bb32171e59.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=1647314&mlfb=5SN6420-8CP"},"ai":{"faq":[{"question":"What is the breaking capacity of the 5SN6420-8CP?","answer":"6 kA per EN 60898 for residential-type installations, and 15 kA per IEC 60947-2 for industrial panel applications. The 15 kA figure governs when the breaker is applied in an industrial distribution board with a higher prospective fault current."},{"question":"Will the 5SN6420-8CP fit a panel designed for the 5SL4363-7?","answer":"Not without rewiring. The 5SN6420-8CP is a 4-pole device at 72 mm width (4 MWU), while the 5SL4363-7 is a 3-pole device at 54 mm width (3 MWU). The 4-pole breaker requires one additional module space and a neutral connection the 3-pole does not."},{"question":"What is the depth of the 5SN6420-8CP?","answer":"76 mm overall depth, with 70 mm installation depth behind the panel surface. This matches the standard SENTRON 5SN family envelope."},{"question":"Where can I buy the 5SN6420-8CP?","answer":"Sourced through independent industrial-automation distribution. Submit an RFQ for current pricing and availability — confirmed at quote time, not from a live stock feed."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SN6420-8CP","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/5SN6420-8CP 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}}