{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"A9N21377","brand":"Schneider Electric","brandSlug":"schneider","productSlug":"A9N21377","canonicalUrl":"https://aoctrl.com/schneider/A9N21377","factsUrl":"https://aoctrl.com/api/mcp/products/A9N21377","rawCanonicalId":null},"summary":{"shortDescription":"Schneider Electric Prodis DT40N, A9N21377, miniature circuit breaker, 20 A, curve D, 1P+N, 6 kA Icn / 10 kA Icu, clip-on DIN rail.","salesMarkdown":"The Schneider Electric A9N21377 is a Prodis DT40N miniature circuit breaker (MCB) rated at 20 A with a D tripping curve, meaning the magnetic trip operates at 10 to 14 times the rated current (10...14 x In). Neutral position is left. Clips onto a DIN rail with toggle control and ON/OFF indication. Breaking capacity is rated at 6 kA Icn per EN/IEC 60898-1 for domestic-type installations, and 10 kA Icu at 230...240 V AC per IEC 60947-2 for industrial panel applications. Clip-on mounting to DIN rail (35 mm) with a 2-pitch width (9 mm per pitch = 18 mm total). The compact 18 mm width per pole saves rail space in crowded enclosures. Certified to both EN/IEC 60898-1 (household-type MCB standard) and EN/IEC 60947-2 (industrial circuit-breaker standard). This dual certification is the key compliance advantage — it covers residential, commercial, and light industrial installations under one part number. Overvoltage category IV (for equipment connected at the origin of the installation, before the main distribution board). Earth-leakage protection requires a separate block (not integrated).","metaTitle":"Schneider Electric A9N21377 DT40N MCB, 20 A, Curve D, 1P+N,","metaDescription":"Schneider Electric A9N21377 DT40N miniature circuit breaker, 20 A rated current, curve D (10-14x In), 1P+N, 6 kA Icn / 10 kA Icu, clip-on DIN rail mount. Active production. Sourced","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["1-Pole MCB (DIN Rail)"],"specifications":{"Depth":"78 mm","Range":"Prodis","Width":"18 mm","Colour":"White","Height":"81 mm","Standards":"EN/IEC 60898-1 EN/IEC 60947-2","Curve code":"D","9 Mm Pitches":"2","Control type":"Toggle","Network type":"AC","Product name":"DT40","Mounting mode":"Clip-on","Quality labels":"NF","Tropicalisation":"2 conforming to IEC 60068-1","lifecycle_stage":"current","Limitation class":"3 conforming to EN/IEC 60898-1","Local signalling":"ON/OFF indication","Mounting support":"DIN rail","Neutral position":"Left","Pollution degree":"3 conforming to IEC 60947-2","Range of product":"ProDis","Breaking capacity":"6000 A Icn at 230 V AC 50 Hz conforming to EN/IEC 60898-1 10 kA Icu at 230...240 V AC 50 Hz conforming to IEC 60947-2","Device short name":"DT40N","Network frequency":"50 Hz","Poles description":"1P + N","Relative humidity":"95 % at 55 °C","Tightening torque":"2 N.m","Device application":"Distribution","Operating altitude":"2000 m","[In] rated current":"20 A","Overvoltage category":"IV","Trip unit technology":"Thermal-magnetic","Electrical durability":"20000 cycles","Mechanical durability":"20000 cycles","Wire stripping length":"13 mm","Connections - terminals":"Tunnel type terminals downstream 0.33...10 mm² flexible Tunnel type terminals downstream 0.75...16 mm² rigid Tunnel type terminals upstream 0.33...10 mm² flexible Tunnel type terminals upstream 0.75...16 mm² rigid","IP degree of protection":"IP20 conforming to IEC 60529","Magnetic tripping limit":"10...14 x In","Earth-leakage protection":"Separate block","Number of protected poles":"1","Product or component type":"Miniature circuit-breaker","Suitability for isolation":"Yes","Contact position indicator":"Yes","Locking options description":"Padlocking device","[Ui] rated insulation voltage":"400 V AC 50 Hz","[Ue] rated operational voltage":"230 V AC 50 Hz between phase and neutral","Ambient air temperature for storage":"-40...70 °C","Ambient air temperature for operation":"-25...70 °C","[Ics] rated service breaking capacity":"7.5 kA 75 % x Icn at 230 V AC 50 Hz conforming to IEC 60947-2 6000 A 100 % x Icn at 230 V AC 50 Hz conforming to EN/IEC 60898-1","[Uimp] rated impulse withstand voltage":"4 kV conforming to IEC 60947-2"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/126344a7fcd017f89ab5ee89be4d8471.pdf","sourceUrl":"https://www.se.com/uk/en/product/A9N21377/dt40-circuit-breaker-dt40n-1p-+-n-20a-d-curve/","alternativesUrl":"https://aoctrl.com/api/mcp/products/A9N21377/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/schneider/A9N21377","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/schneider/A9N21377 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}}