{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY8208-8","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY8208-8","canonicalUrl":"https://aoctrl.com/siemens/5SY8208-8","factsUrl":"https://aoctrl.com/api/mcp/products/5SY8208-8","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY8 series, miniature circuit breaker, 2-pole, D tripping characteristic, 8 A rated current, 400 V AC, 40 kA breaking capacity per IEC 60947-2, 5SY8208-8.","salesMarkdown":"The Siemens 5SY8208-8 is a 2-pole miniature circuit breaker from the SENTRON 5SY8 series, with a D tripping characteristic and an 8 A rated current at 400 V AC. It's also rated 15 kA at DC per IEC 60947-2 for up to 72 V DC, and carries a 5 kA interrupting rating under UL 1077 and CSA C22.2 No. 235 — so it's accepted in North American control-panel applications where UL 508A compliance is required, not just IEC markets. The silicon-free and halogen-free construction makes it suitable for clean-room or sensitive electronics environments where outgassing contaminants are a concern. ## Mounting and wiring in the panel Terminal clamps accept solid or stranded copper from 0.75 mm² up to 35 mm², with a recommended tightening torque of 2.5 to 3.5 N·m. Combined terminals top and bottom mean you can feed through or loop out without separate busbar connectors.","metaTitle":"Siemens 5SY8208-8 SENTRON MCB, 2P D 8A, 40kA IEC","metaDescription":"Siemens 5SY8208-8 SENTRON miniature circuit breaker, 2-pole, D-curve, 8 A rated, 40 kA breaking capacity at 400 V AC per IEC 60947-2. In current production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["2-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Solid":"0.75 ... 35 mm²","Width":"36 mm","title":"5SY8208-8","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, 2P, D8","Halogen-Free":"Yes","Silicon-Free":"Yes","Wertebereich":"-25 ... +55 °C","Mounting type":"Quick assembly system","Number of poles":"2","Type of voltage":"AC","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Ambient temperature":"-40 ... +75 °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":"2","Number of poles / Note":"2P","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":"8 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":"40 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/311a9e526183480e7b088513cf79a400.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=125288&mlfb=5SY8208-8"},"ai":{"faq":[{"question":"Where can I buy the 5SY8208-8 and get a price?","answer":"The 5SY8208-8 is sourced and quoted to order through independent distribution. Submit an RFQ for current availability and pricing — confirmed at quote time, not a published stock figure."},{"question":"What does the D tripping characteristic mean for this 8 A breaker?","answer":"The D curve trips magnetically at 10 to 20 times rated current (80 to 160 A for this 8 A unit), so it handles high inrush from motors, transformers, or welding gear without nuisance tripping on startup. Thermal overload protection still kicks in on sustained overcurrents above 8 A."},{"question":"What is the breaking capacity of the 5SY8208-8 at 400 V AC?","answer":"40 kA at 400 V AC per IEC 60947-2. It also carries 15 kA at DC up to 72 V per IEC 60947-2, and 5 kA under UL 1077 / CSA C22.2 No. 235 for North American control-panel use."},{"question":"What wire sizes does the 5SY8208-8 accept?","answer":"Solid or stranded copper from 0.75 mm² up to 35 mm². Torque the terminals to 2.5–3.5 N·m. Combined top and bottom terminals let you feed through without extra busbars."},{"question":"What compliance documentation is available for the 5SY8208-8?","answer":"The breaker is rated per IEC 60947-2, UL 1077, and CSA C22.2 No. 235. It is silicon-free and halogen-free. Standard Siemens SENTRON declarations (CE, UKCA, RoHS, REACH) apply — consult the product documentation for specific certificate numbers."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY8208-8","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/5SY8208-8 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}}