{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY8263-8BB08","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY8263-8BB08","canonicalUrl":"https://aoctrl.com/siemens/5SY8263-8BB08","factsUrl":"https://aoctrl.com/api/mcp/products/5SY8263-8BB08","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY8263-8BB08, miniature circuit breaker, 2-pole, D tripping characteristic, 63 A rated at 400 V AC, 20 kA breaking capacity per IEC 60947-2, magnetic-only operation.","salesMarkdown":"That makes it a straight short-circuit protector for circuits where overload protection is handled upstream or by the load itself. For UL 1077 / CSA C22.2 No. 235 applications, the interrupting rating is 5 kA at 400 V AC, so verify your available fault current if the panel carries a UL/CSA sticker. On DC circuits, it is rated 72 V maximum, so it works in 48 V or 60 V DC control buses but not on a 110 V DC battery bank. Two-pole (2P) design in a 36 mm wide housing — that is 2 modular width units on a DIN rail. Rated for use in mechanical engineering and industrial environments per the manufacturer's suitability statement. The product function code per DIN EN 61346-2 is F (protective device).","metaTitle":"Siemens 5SY8263-8BB08 SENTRON MCB, 2P D 63A 400V AC, 20kA IE","metaDescription":"Siemens 5SY8263-8BB08 SENTRON miniature circuit breaker, 2-pole, D-curve, 63A rated at 400V AC, 20kA breaking capacity per IEC 60947-2. Active 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","Width":"36 mm","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","Rated Value":"50/60 Hz","Halogen-Free":"Yes","Silicon-Free":"Yes","Number Of Poles":"2","Type Of Voltage":"AC","lifecycle_stage":"current","Fastening Method":"Quick assembly system","Mounting Position":"any","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"3","Product Designation":"Miniature circuit breaker","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"Yes","Design Of The Product":"Only magnetic tripping operation","Number Of Poles / Note":"2P","acc. to DIN EN 61346-2":"F","Combined Terminal Bottom":"Yes","Suitability For Operation":"Mechanical engineering / industry","Number Of Modular Width Units":"2","Tripping Characteristic Class":"D","at DC / rated value / maximum":"72 V","Position / Of Power Supply Cord":"Any","acc. to IEC 60947-2 / rated value":"20 kA","Product Feature / Touch Protection":"Yes","supply voltage / at AC / rated value":"400 V","Influence Of The Surrounding Temperature":"max. 95% to 55°C, max. 55% to 70°C, max. 35% to 75°C","operational current / at AC / rated value":"63 A","at AC / acc. to UL 1077 and CSA C22.2 No.235":"5 kA","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"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/d98b5dae5b5dd8dfb0ecd299afe520a9.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=471964&mlfb=5SY8263-8BB08","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY8263-8BB08/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of 5SY8263-8BB08?","answer":"20 kA per IEC 60947-2 at 400 V AC, and 5 kA per UL 1077 / CSA C22.2 No. 235 at 400 V AC."},{"question":"What does the D tripping characteristic mean on this breaker?","answer":"The D-curve allows magnetic trip at 10–14× rated current (630–882 A for this 63 A breaker), so it is selected for loads with high inrush like motors, transformers, or capacitor banks."},{"question":"Where can I buy 5SY8263-8BB08?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"Will 5SY8263-8BB08 drop into a panel specified around 5SY7210-7CC?","answer":"Both are SENTRON 2-pole MCBs on a 36 mm footprint, so the mechanical fit is the same. The 5SY8263-8BB08 carries a higher 63 A rating and D-curve versus the 5SY7210-7CC's lower rating, so the electrical substitution depends on whether the circuit's load and fault current match."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY8263-8BB08","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/5SY8263-8BB08 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}}