{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY4440-8FA","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY4440-8FA","canonicalUrl":"https://aoctrl.com/siemens/5SY4440-8FA","factsUrl":"https://aoctrl.com/api/mcp/products/5SY4440-8FA","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY4440-8FA, 4-pole miniature circuit breaker, D-tripping characteristic, 40 A rated current, 10 kA breaking capacity at 400 V AC per EN 60898, 4 width units, IP20.","salesMarkdown":"## Siemens 5SY4440-8FA – 40 A D-curve MCB for industrial panel protection The Siemens 5SY4440-8FA is a 4-pole miniature circuit breaker from the SENTRON series, rated 40 A with a D tripping characteristic and a 10 kA breaking capacity at 400 V AC. Mounting snaps onto a DIN rail (quick assembly system per) in any orientation. The 4-pole (4P) form factor occupies 4 width units (72 mm) on the rail, with a depth of 76 mm and an installation depth of 70 mm behind the panel surface. Terminals accept 0.75–35 mm² solid or stranded copper, tightened to 3.5 N·m — suitable for incoming supply cables up to 35 mm² and outgoing branch circuits. ## Voltage ratings and application boundaries Maximum DC voltage is 72 V — this is not a DC-rated breaker for solar or battery strings at higher voltages. Overvoltage category III suits fixed-installation distribution boards. The breaker is sealable and touch-protected per IP20 with connected conductors, meaning it is safe for use in enclosed panels but not in wet or dusty environments without an outer enclosure. Halogen-free and silicon-free construction.","metaTitle":"Siemens 5SY4440-8FA SENTRON MCB, 4P D 40 A 10 kA","metaDescription":"Siemens 5SY4440-8FA SENTRON miniature circuit breaker, 4-pole, D-curve, 40 A, 10 kA breaking capacity per EN 60898. Active production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["4-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Solid":"0.75 ... 35 mm²","Width":"72 mm","title":"5SY4440-8FA","Height":"90 mm","Sealable":"Yes","Stranded":"0.75 ... 35 mm²","Rated Value":"50/60 Hz","description":"Miniature circuit breaker 400 V 10kA, 4-pole, 40A, D=70 mm as counter preliminary miniature circuit breaker","Halogen-Free":"Yes","Silicon-Free":"Yes","Mounting type":"Quick assembly system","During Storage":"-40 ... +75 °C","Number of poles":"4","Type of voltage":"AC","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Ambient temperature":"-25 ... +55 °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":"40 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,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/b61fc5c240a52030b48a4c636d0cbe71.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=123741&mlfb=5SY4440-8FA"},"ai":{"faq":[{"question":"Will the 5SY4440-8FA drop into a panel specified around the 5SY3132-6 without rewiring?","answer":"The 5SY4440-8FA is a 4-pole, 40 A D-curve breaker in a 4-width-unit footprint (72 mm). The 5SY3132-6 is a different pole/current/curve variant; physical rail fit is the same DIN-rail system, but terminal sizing and circuit protection coordination must be re-evaluated. No direct drop-in without verifying the load and upstream protection."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY4440-8FA","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/5SY4440-8FA when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:51:03.652Z","lastPublished":"2026-08-11T15:51:03.652Z","indexable":true}}