{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY8402-8","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY8402-8","canonicalUrl":"https://aoctrl.com/siemens/5SY8402-8","factsUrl":"https://aoctrl.com/api/mcp/products/5SY8402-8","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY8 series, 4-pole miniature circuit breaker, D tripping characteristic, 2 A rated current at 400 V AC, 70 kA breaking capacity per IEC 60947-2.","salesMarkdown":"The Siemens 5SY8402-8 is a 4-pole miniature circuit breaker from the SENTRON 5SY8 series, rated 2 A at 400 V AC with a D tripping characteristic. ## Breaking capacity — what the ratings actually mean for your panel For DC circuits it's rated 15 kA per the same standard, and under UL 1077 / CSA C22.2 No. 235 it's listed at 5 kA. The UL figure is lower because that standard tests at a different fault profile; if your panel requires UL listing, the 5 kA is the number to coordinate with the upstream SCCR. The 70 kA IEC rating gives you headroom on most industrial distribution boards without needing a current-limiting upstream breaker. ## Mounting and wiring — drops into a standard 4-MU DIN-rail slot 72 mm wide (4 width units), 90 mm tall, 76 mm deep with a 70 mm installation depth. Accepts solid or stranded conductors from 0.75 mm² up to 35 mm² at the screw terminals; torque to 2.5–3.5 N·m. IP20 with conductors connected, so it's panel-internal only — no washdown exposure. Terminal comb available top and bottom for daisy-chaining phases. Mounting position any, ambient -25 to +55 °C, storage -40 to +75 °C.","metaTitle":"Siemens 5SY8402-8 SENTRON MCB, 4P D-curve 2A 400V","metaDescription":"Siemens SENTRON 5SY8402-8 miniature circuit breaker, 4-pole, D-curve, 2 A rated at 400 V AC, 70 kA breaking capacity per IEC 60947-2. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["4-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Solid":"0.75 ... 35 mm²","Width":"72 mm","title":"5SY8402-8","Height":"90 mm","Sealable":"Yes","Stranded":"0.75 ... 35 mm²","Rated Value":"50/60 Hz","description":"Miniature circuit breaker 400 V D=70 mm 25 kA according to EN 60947-2, 4P, D2","Halogen-Free":"Yes","Silicon-Free":"Yes","Mounting type":"Quick assembly system","During Storage":"-40 ... +75 °C","Number of poles":"4","Type of voltage":"AC","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Ambient temperature":"-25 ... +55 °C","Product designation":"Miniature circuit breaker","Protection class IP":"IP20, with connected conductors","at AC / rated value":"400 V","Overvoltage category":"III","Combined Terminal Top":"Yes","Number of width units":"4","Number of poles / Note":"4P","acc. to DIN EN 61346-2":"F","acc. to DIN EN 81346-2":"F","Combined Terminal Bottom":"Yes","circuit-breaker / Design":"5SY8","Suitability for operation":"Mechanical engineering / industry","Current / at AC / rated value":"2 A","Tripping characteristic class":"D","at DC / rated value / maximum":"72 V","Position / of power supply cord":"Any","acc. to IEC 60947-2 / rated value":"70 kA","Product feature / Touch protection":"Yes","Influence of the surrounding temperature":"max. 95% to 55°C, max. 55% to 70°C, max. 35% to 75°C","at DC / acc. to IEC 60947-2 / rated value":"15 kA","at AC / acc. to UL 1077 and CSA C22.2 No.235":"5 kA","Tightening torque / with screw-type terminals":"2.5 ... 3.5 N·m","Product function / neutral conductor switching":"No","with multi-phase operation / at AC / rated value":"440 V","with single-phase operation / at AC / rated value":"440 V","Mechanical service life (switching cycles) / typical":"10 000","Tightening torque [lbf·in] / with screw-type terminals":"22 ... 31 lbf·in","AWG number / as coded connectable conductor cross section":"18 ... 4"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/8fdb53bdb0a75a99199a89403cb954be.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=463549&mlfb=5SY8402-8"},"ai":{"faq":[{"question":"Where can I buy 5SY8402-8 and how do I get a price?","answer":"This part is sourced to order through independent distribution. Submit an RFQ — availability and current pricing are confirmed at quote time."},{"question":"What is 5SY8402-8's listed depth?","answer":"The depth is 76 mm, with an installation depth of 70 mm."},{"question":"What conductor sizes does 5SY8402-8 accept?","answer":"It accepts solid or stranded conductors from 0.75 mm² up to 35 mm² at the screw terminals."},{"question":"Does 5SY8402-8 have UL or CSA approvals?","answer":"It carries a UL 1077 and CSA C22.2 No. 235 listing with a 5 kA breaking capacity at AC."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY8402-8","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/5SY8402-8 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}}