{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY4450-8FA","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY4450-8FA","canonicalUrl":"https://aoctrl.com/siemens/5SY4450-8FA","factsUrl":"https://aoctrl.com/api/mcp/products/5SY4450-8FA","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY4450-8FA, 4-pole miniature circuit breaker, D tripping characteristic, 50 A rated current, 10 kA breaking capacity at 400 V AC, 72 mm wide (4 MW), halogen-free, silicon-free.","salesMarkdown":"## What this breaker is for ## DIN-rail fit and terminal capacity Depth is 76 mm, height 90 mm, so it fits flush in a standard 100 mm deep enclosure with the gland plate intact. Terminals accept solid or stranded conductors from 0.75 mm² up to 35 mm² — enough for a 50 A feed using 10 mm² or 16 mm² Cu. Screw terminals with 3.5 N·m tightening torque, combined top and bottom entry. Sealable cover for tamper-proofing after inspection. Operating ambient -25 to +55 °C; storage -40 to +75 °C. Halogen-free and silicon-free construction, important for clean-room or semiconductor-adjacent installations where outgassing contaminates optics or contacts.","metaTitle":"Siemens SENTRON 5SY4450-8FA MCB, 4P D-curve 50 A, 10 kA","metaDescription":"Siemens SENTRON 5SY4450-8FA 4-pole miniature circuit breaker, D tripping characteristic, 50 A rated current, 10 kA breaking capacity at 400 V AC. Current production. Quoted to orde","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["Miniature Circuit Breakers (MCB)"],"specifications":{"Depth":"76 mm","Solid":"0.75 ... 35 mm²","Width":"72 mm","Height":"90 mm","Sealable":"Yes","Stranded":"0.75 ... 35 mm²","Rated Value":"50/60 Hz","Halogen-Free":"Yes","Silicon-Free":"Yes","Wertebereich":"-25 ... +55 °C","Mounting type":"Quick assembly system","Number of poles":"4","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","Design of the product":"As automatic meter","Number of width units":"4","Number of poles / Note":"4P","acc. to DIN EN 81346-2":"F","Combined Terminal Bottom":"Yes","Suitability for operation":"Mechanical engineering / industry","Current / at AC / rated value":"50 A","Tripping characteristic class":"D","at DC / rated value / maximum":"72 V","acc. to EN 60898 / rated value":"10 kA","Position / of power supply cord":"Any","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","Tightening torque / with screw-type terminals":"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":"31 lbf·in","AWG number / as coded connectable conductor cross section":"18 ... 4"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/45bced02a0806b629a45eb8691a839f5.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=280140&mlfb=5SY4450-8FA","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY4450-8FA/alternatives.json"},"ai":{"faq":[{"question":"Where can I buy the 5SY4450-8FA and how is it quoted?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"What compliance documentation does Siemens provide for the 5SY4450-8FA?","answer":"The breaker carries a CE mark per the Low Voltage Directive and is designed to EN 60898. The SENTRON series also supports UL 1077 recognition for branch-circuit marking where applicable; confirm the specific UL file number with the order code."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY4450-8FA","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/5SY4450-8FA 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}}