{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY6040-6","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY6040-6","canonicalUrl":"https://aoctrl.com/siemens/5SY6040-6","factsUrl":"https://aoctrl.com/api/mcp/products/5SY6040-6","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON miniature circuit breaker, 1P+N, B-curve, 40 A, 6 kA breaking capacity per EN 60898, 1 MW width, compact design.","salesMarkdown":"## What the ratings mean for fit The Siemens SENTRON 5SY6040-6 is a 1P+N miniature circuit breaker with a B tripping characteristic, rated 40 A at 30 °C and 230 V AC, with a 6 kA breaking capacity per EN 60898. That B-curve means it trips between 3× and 5× rated current — designed for resistive and light inductive loads like lighting circuits, small heaters, and control transformers in residential and infrastructure panels. The 6 kA interrupting rating is the maximum fault current it can safely clear at 230 V; for most domestic and light commercial distribution boards this is sufficient, but verify your prospective short-circuit current at the installation point. The 1P+N pole design switches both line and neutral, with the neutral pole switching but not protected — common in single-phase final circuits where neutral isolation is required. At elevated ambient temperatures the breaker derates: 38 A at 40 °C, 37.2 A at 45 °C. That matters when the MCB sits in a crowded enclosure with other heat sources — the 40 A rating is only valid at 30 °C ambient. If your panel runs at 40 °C, the continuous load should not exceed 38 A. ## Panel integration and mounting The 5SY6040-6 snaps onto standard DIN rail (EN 60715) and occupies one modular width unit (18 mm). Mounting position is any — vertical, horizontal, or flat — which simplifies layout in tight enclosures. Installation depth is 70 mm; total depth including the breaker body is 76 mm. The IP20 rating (with connected conductors) means it is protected against finger contact but not water ingress — standard for indoor distribution boards. Touch protection is built in, so accidental contact with live terminals during maintenance is prevented. ## Compliance and environmental The breaker is halogen-free and silicon-free, which matters for clean-room or sensitive electronics environments where outgassing can cause contact corrosion or optical haze. It is sealable (can be locked in the OFF position for lockout/tagout). Vibration resistance per IEC 60068-2-6 is confirmed, so it holds up in transport or near rotating machinery. Pollution degree 2 and overvoltage category III suit fixed installations in residential and commercial buildings.","metaTitle":"Siemens SENTRON 5SY6040-6 MCB, 1P+N, B 40 A, 6 kA","metaDescription":"Siemens SENTRON 5SY6040-6 miniature circuit breaker, 1P+N, B-curve, 40 A, 6 kA breaking capacity per EN 60898. 18 mm width, IP20. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["1-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Width":"18 mm","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","Halogen-Free":"Yes","Silicon-Free":"Yes","Design Of Pole":"1P+N","lifecycle_stage":"current","Fastening Method":"standard rail","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","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"No","Design Of The Product":"Miniature circuit breaker compact","Energy Limitation Class":"3","at 30 °C / rated value":"40 A","at 40 °C / rated value":"38 A","at 45 °C / rated value":"37.2 A","Combined Terminal Bottom":"No","Suitability For Operation":"Residential buildings/infrastructure","Number Of Modular Width Units":"1","Tripping Characteristic Class":"B","acc. to EN 60898 / rated value":"6 kA","Position / Of Power Supply Cord":"Any","Product Feature / Touch Protection":"Yes","Type Of Voltage / Of The Operating Voltage":"AC","vibration resistance / acc. to IEC 60068-2-6":"Yes","insulation voltage (Ui) / at AC / rated value":"250 V","with single-phase operation / at AC / maximum":"250 V","Product Component / Neutral Conductor Switching":"Yes","Mechanical Service Life (Switching Cycles) / Typical":"4 000"}},"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=358079&mlfb=5SY6040-6","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY6040-6/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of 5SY6040-6?","answer":"6 kA per EN 60898 at 230 V AC."},{"question":"What is the closest functional second-source for 5SY6040-6?","answer":"The 5SL6016-7KL is a similar Siemens SENTRON 1P+N B-curve MCB, but verify the rated current and breaking capacity against your specific load — the 5SY6040-6 is rated 40 A / 6 kA."},{"question":"Where can I buy 5SY6040-6?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY6040-6","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/5SY6040-6 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}}