{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY5440-7","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY5440-7","canonicalUrl":"https://aoctrl.com/siemens/5SY5440-7","factsUrl":"https://aoctrl.com/api/mcp/products/5SY5440-7","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON, 5SY5440-7, 4-pole miniature circuit breaker, 40 A rated, C tripping characteristic, 10 kA breaking capacity per EN 60898, 4 MW wide, IP20.","salesMarkdown":"The Siemens 5SY5440-7 is a SENTRON 4-pole miniature circuit breaker rated 40 A at AC with a C tripping characteristic and a 10 kA breaking capacity per EN 60898. The 4-pole design (4P) switches all three phases plus the neutral, which is what you want for a three-phase motor feeder where you need to isolate the neutral for maintenance. The 4 MW width (72 mm) takes up four 18 mm modular slots on the DIN rail — standard for a 4-pole MCB in this class. ## Temperature derating — the real-world current The 40 A rating holds at 35 °C ambient. At 40 °C it derates to 38.4 A; at 50 °C it's 36.76 A; at 60 °C it's 35.04 A. The humidity limits are 95% RH up to 55 °C, then dropping to 35% RH at 75 °C, so a sealed outdoor enclosure that traps moisture could be a problem. The quick-assembly system means you can gang multiple breakers on a busbar without extra hardware.","metaTitle":"Siemens 5SY5440-7 SENTRON MCB, 4P 40A C-Curve, 10kA","metaDescription":"Siemens 5SY5440-7 SENTRON 4-pole MCB, 40 A rated, C-curve, 10 kA breaking capacity per EN 60898. IP20. Current lifecycle stage. Quoted to order against RFQ.","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","Design Of Pole":"4P","Number Of Poles":"4","lifecycle_stage":"current","Fastening Method":"Quick assembly system","Mounting Position":"any","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"2","Product Designation":"Miniature circuit breaker","acc. to IEC 81346-2":"F","at AC / rated value":"40 A","at DC / rated value":"880 V","protection class IP":"IP20, with connected conductors","Overvoltage Category":"II","Combined Terminal Top":"Yes","acc. to DIN EN 61346-2":"F","Energy Limitation Class":"3","at 35 °C / rated value":"40 A","at 40 °C / rated value":"38.4 A","at 45 °C / rated value":"37.6 A","at 50 °C / rated value":"36.76 A","at 55 °C / rated value":"35.92 A","at 60 °C / rated value":"35.04 A","Combined Terminal Bottom":"Yes","Suitability For Operation":"universal current","at DC / acc. to EN 60898-2":"10 kA","Number Of Modular Width Units":"4","Tripping Characteristic Class":"C","acc. to EN 60898 / rated value":"10 kA","Position / Of Power Supply Cord":"AC as required, observe DC polarity","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","Type Of Voltage / Of The Operating Voltage":"AC/DC","vibration resistance / acc. to IEC 60068-2-6":"±1mm at 5 to 25Hz; 50m/s² at 25 to 150Hz","Product Component / Neutral Conductor Switching":"No","with multi-phase operation / at AC / rated value":"440 V","operating voltage / at DC / rated value / maximum":"1 000 V","with single-phase operation / at AC / rated value":"440 V","Mechanical Service Life (Switching Cycles) / Typical":"5 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/631b88db296f6265f931512e75ef0ba6.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=66216&mlfb=5SY5440-7","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY5440-7/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of the 5SY5440-7?","answer":"It carries a 10 kA breaking capacity per EN 60898 at AC, and 10 kA per EN 60898-2 at DC."},{"question":"Where can I buy the 5SY5440-7?","answer":"The 5SY5440-7 is sourced and quoted to order against an RFQ through independent distribution channels; availability and current pricing are confirmed at quote time."},{"question":"What compliance documentation does Siemens provide for 5SY5440-7?","answer":"The part carries IEC 60898 certification (EN 60898) and is classified per IEC 81346-2 and DIN EN 61346-2 as function F. It is halogen-free and silicon-free. The product is rated IP20 with connected conductors."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY5440-7","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/5SY5440-7 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}}