{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY8663-8","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY8663-8","canonicalUrl":"https://aoctrl.com/siemens/5SY8663-8","factsUrl":"https://aoctrl.com/api/mcp/products/5SY8663-8","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY8663-8, 4-pole (3P+N) miniature circuit breaker, D tripping characteristic, rated 63 A at 45 °C, 400 V AC, 20 kA breaking capacity per IEC 60947-2.","salesMarkdown":"## Integrator's spec recap The Siemens 5SY8663-8 is a SENTRON miniature circuit breaker in a 4-pole 3P+N configuration, D-curve, rated 63 A at 45 °C with a 20 kA breaking capacity per IEC 60947-2 at 400 V AC. The D characteristic (10–20× In) handles high inrush loads like motor starters and transformer primaries without nuisance tripping. Temperature range -40 to 75 °C, with derated current at higher ambients: 61.42 A at 50 °C, 59.79 A at 55 °C. That derate curve matters if the breaker sits near heat sources in a crowded cabinet. ## Sourcing & fit The 4-pole D-curve 63 A footprint is standard for motor branch circuits and high-inrush loads in industrial panels — verify the mounting rail and busbar spacing match your existing layout.","metaTitle":"Siemens 5SY8663-8 SENTRON MCB, 4P D-63A, 20kA IEC","metaDescription":"Siemens 5SY8663-8 SENTRON miniature circuit breaker, 4-pole 3P+N, D-curve 63A, 20kA breaking capacity per IEC 60947-2. Quoted to order — request RFQ for current pricing and availab","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Miniature Circuit Breakers (MCB)"],"specifications":{"Depth":"76 mm","Width":"72 mm","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","Halogen-Free":"Yes","Silicon-Free":"Yes","Number Of Poles":"4","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","acc. to IEC 81346-2":"F","at AC / rated value":"400 V","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"Yes","Number Of Poles / Note":"3P+N","acc. to DIN EN 61346-2":"F","at 45 °C / rated value":"63 A","at 50 °C / rated value":"61.42 A","at 55 °C / rated value":"59.79 A","Combined Terminal Bottom":"Yes","Suitability For Operation":"Mechanical engineering / industry","Number Of Modular Width Units":"4","Tripping Characteristic Class":"D","Position / Of Power Supply Cord":"Any","acc. to IEC 60947-2 / rated value":"20 kA","Product Feature / Touch Protection":"Yes","Supply Voltage Frequency / Rated Value":"50/60 Hz","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","vibration resistance / acc. to IEC 60068-2-6":"±1mm at 5 to 25Hz; 50m/s² at 25 to 150Hz","Product Function / Neutral Conductor Switching":"Yes","with multi-phase operation / at AC / rated value":"440 V","operating voltage / at DC / rated value / maximum":"72 V","with single-phase operation / at AC / rated value":"440 V","Mechanical Service Life (Operating Cycles) / Typical":"10 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/2886af114d117a35196192325a53e426.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=458905&mlfb=5SY8663-8","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY8663-8/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of 5SY8663-8?","answer":"20 kA per IEC 60947-2 at 400 V AC, 15 kA DC per IEC 60947-2, and 5 kA per UL 1077 and CSA C22.2 No. 235."},{"question":"What is the tripping characteristic of 5SY8663-8?","answer":"D-curve (10–20× In), designed for high-inrush loads such as motors and transformers."},{"question":"Where can I buy 5SY8663-8?","answer":"Sourced to order against an RFQ through independent distribution. Contact us for current pricing and availability."},{"question":"Will 5SY8663-8 drop into a panel specified around 5SY6613-8 without rewiring?","answer":"Both are 4-pole SENTRON MCBs on the same quick-assembly system, so the mounting rail and width (72 mm / 4 MW) are identical. The key difference is the tripping characteristic: 5SY8663-8 is D-curve (10–20× In), while 5SY6613-8 is a different curve. Verify the load's inrush profile before swapping — D-curve may trip on moderate surges that a higher-curve breaker would pass."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY8663-8","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/5SY8663-8 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}}