{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY4450-7KK11","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY4450-7KK11","canonicalUrl":"https://aoctrl.com/siemens/5SY4450-7KK11","factsUrl":"https://aoctrl.com/api/mcp/products/5SY4450-7KK11","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY4450-7KK11, 4-pole miniature circuit breaker, C-curve, 50 A rated at AC, 10 kA (EN 60898) / 15 kA (IEC 60947-2).","salesMarkdown":"## Rating Reality — Temperature Derating and Breaking Capacity The 50 A rating holds at 35 °C ambient. At 40 °C it derates to 48 A, at 50 °C to 45.95 A, and at 60 °C to 43.8 A. The C-curve's magnetic trip threshold (5–10× In) means a 50 A unit trips instantaneously between 250 A and 500 A, which coordinates well with downstream branch protection for motor starters or VFD input feeds. If your facility's transformer is close to the panel and the SCCR study shows 12 kA at the distribution board, this breaker covers it. The 10 kA EN 60898 rating is the domestic/commercial standard — useful for coordination studies but not the binding figure in an industrial BOM. ## Panel Integration and Compliance Notes Combined terminal top and bottom — wire entry from either direction, no need to flip the breaker for top-feed vs bottom-feed panels. Sealable (padlockable) for lockout/tagout compliance. Touch protection is built in (IPXXB finger-safe).","metaTitle":"Siemens 5SY4450-7KK11 SENTRON MCB, 4P C-Curve 50A, 10kA/15kA","metaDescription":"Siemens SENTRON 5SY4450-7KK11 4-pole miniature circuit breaker, 50 A rated, C tripping characteristic, 10 kA (EN 60898) / 15 kA (IEC 60947-2) breaking capacity. Current lifecycle s","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"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":"50 A","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"Yes","Design Of The Product":"For railway applications","Number Of Poles / Note":"4P","acc. to DIN EN 61346-2":"F","Energy Limitation Class":"3","at 35 °C / rated value":"50 A","at 40 °C / rated value":"48 A","at 45 °C / rated value":"47 A","at 50 °C / rated value":"45.95 A","at 55 °C / rated value":"44.9 A","at 60 °C / rated value":"43.8 A","Combined Terminal Bottom":"Yes","Suitability For Operation":"Mechanical engineering / industry","Number Of Modular Width Units":"4","Tripping Characteristic Class":"C","acc. to EN 60898 / rated value":"10 kA","Position / Of Power Supply Cord":"Any","acc. to IEC 60947-2 / rated value":"15 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":"No","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":null,"sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=72140&mlfb=5SY4450-7KK11","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY4450-7KK11/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of this MCB?","answer":"The 5SY4450-7KK11 has a 10 kA breaking capacity per EN 60898 and 15 kA per IEC 60947-2. For industrial panels where the prospective fault current exceeds 10 kA, the 15 kA IEC rating is the binding figure."},{"question":"What is the temperature derating for the 5SY4450-7KK11?","answer":"The 50 A rating holds at 35 °C. It derates to 48 A at 40 °C, 47 A at 45 °C, 45.95 A at 50 °C, 44.9 A at 55 °C, and 43.8 A at 60 °C. Size your continuous load to the derated value for the expected panel ambient."},{"question":"Will the 5SY4450-7KK11 drop into a panel designed for the 5SY4140-7?","answer":"The 5SY4450-7KK11 shares the same 4-pole, 4-module-wide (72 mm) DIN-rail footprint as the 5SY4140-7, so it fits the same busbar and enclosure layout. The difference is the current rating (50 A vs 40 A) and the C-curve vs B-curve — verify that the tripping characteristic and load current match your branch circuit design before swapping."},{"question":"Where can I buy the 5SY4450-7KK11 and how is it quoted?","answer":"The 5SY4450-7KK11 is sourced and quoted to order against an RFQ through independent industrial-automation distribution. Availability and current pricing are confirmed at quote time; submit an RFQ for your volume and delivery requirements."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY4450-7KK11","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/5SY4450-7KK11 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}}