{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY7440-8","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY7440-8","canonicalUrl":"https://aoctrl.com/siemens/5SY7440-8","factsUrl":"https://aoctrl.com/api/mcp/products/5SY7440-8","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY7 series, 4-pole miniature circuit breaker, D tripping characteristic, 40 A rated current, 400 V AC, 15 kA (EN 60898) / 20 kA (IEC 60947-2), 4 width units.","salesMarkdown":"That means the neutral pole is a solid through-bar or a switched pole that doesn't open the neutral under fault; confirm your circuit design expects a solid neutral path. ## Deployment and environment The operating temperature range spans -40 °C to 75 °C, with a derating curve above 55 °C: the breaker can handle up to 95 % relative humidity at 55 °C, tapering to 35 % at 75 °C. The breaker is sealable, which allows a panel builder or inspector to lock the toggle in the ON or OFF position with a padlock — useful for lockout/tagout procedures during maintenance. Touch protection is built into the terminals, so live parts are not accessible when the breaker is installed in a panel with the cover closed. The breaker is designed and tested to EN 60898 (for residential and similar installations) and IEC 60947-2 (for industrial applications). The UL/CSA listing is at 5 kA per UL 1077 and CSA C22.2 No. 235, which covers supplementary protectors for North American panels. For DC circuits, the breaker is rated 72 V maximum with a 15 kA interrupting capacity per IEC 60947-2. The product designation follows DIN EN 61346-2 and DIN EN 81346-2 letter code F (protective device). Compliance documentation — RoHS, REACH, CE, UKCA, and the manufacturer's declaration of conformity — is available upon request as part of the standard technical documentation package for this SENTRON series.","metaTitle":"Siemens 5SY7440-8 SENTRON MCB, 4P D 40 A, 400 V AC","metaDescription":"Siemens 5SY7440-8 SENTRON 4-pole miniature circuit breaker, D-curve, 40 A, 400 V AC, 15 kA (EN 60898) / 20 kA (IEC 60947-2). Current production, available to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["4-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Width":"72 mm","title":"5SY7440-8","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","Rated Value":"50/60 Hz","description":"Miniature circuit breaker 400 V 15kA, 4-pole, D, 40A, D=70 mm","Halogen-Free":"Yes","Silicon-Free":"Yes","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","Degree Of Pollution":"3","Product Designation":"Miniature circuit breaker","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"Yes","Number Of Width Units":"4","Number Of Poles / Note":"4P","acc. to DIN EN 61346-2":"F","acc. to DIN EN 81346-2":"F","Combined Terminal Bottom":"Yes","circuit-breaker / Design":"5SY7","Suitability For Operation":"Mechanical engineering / industry","Tripping Characteristic Class":"D","at DC / rated value / maximum":"72 V","acc. to EN 60898 / rated value":"15 kA","Position / Of Power Supply Cord":"Any","acc. to IEC 60947-2 / rated value":"20 kA","Product Feature / Touch Protection":"Yes","supply voltage / at AC / rated value":"400 V","operating current / at AC / rated value":"40 A","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","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"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/ac865ccf453e0f0ad9050124ef813e11.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=511505&mlfb=5SY7440-8"},"ai":{"faq":[{"question":"Where can I buy the 5SY7440-8?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution channels. Availability and current pricing are confirmed at quote time."},{"question":"What is the closest functional second-source to the 5SY7440-8?","answer":"The 5SY7140-8CC is a close functional peer within the same SENTRON 5SY7 series — same 4-pole, 40 A, D-curve configuration — but its interrupting rating differs; verify your panel's available fault current before substituting."},{"question":"Will the 5SY7440-8 drop into a panel specified around the 5SY7140-8CC without rewiring?","answer":"Yes, both breakers share the same 4-pole, 72 mm wide DIN-rail footprint and terminal arrangement, so the 5SY7440-8 is a direct mechanical and electrical drop-in replacement. Confirm the interrupting rating matches your fault-current study."},{"question":"What compliance documentation is available for the 5SY7440-8?","answer":"Standard documentation includes the manufacturer's declaration of conformity to EN 60898 and IEC 60947-2, plus RoHS, REACH, CE, and UKCA declarations. UL and CSA listings are at 5 kA per UL 1077 and CSA C22.2 No. 235."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY7440-8","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/5SY7440-8 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}}