{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"A9N21390","brand":"Schneider Electric","brandSlug":"schneider","productSlug":"A9N21390","canonicalUrl":"https://aoctrl.com/schneider/A9N21390","factsUrl":"https://aoctrl.com/api/mcp/products/A9N21390","rawCanonicalId":null},"summary":{"shortDescription":"Schneider Electric ProDis DT40N, miniature circuit breaker, 40 A, 3P, C-curve, 6 kA Icn / 10 kA Icu, clip-on DIN rail, white.","salesMarkdown":"## 40 A, 3-pole C-curve MCB for distribution boards The Schneider Electric A9N21390 is a DT40N miniature circuit breaker from the ProDis range, rated 40 A with a C-curve trip characteristic (magnetic tripping at 5 to 10 × In). Three poles protected, thermal-magnetic trip unit, 50 Hz AC network. The 6 kA Icn at 400 V AC (per EN/IEC 60898-1) covers standard domestic and light commercial distribution boards; the 10 kA Icu at 400–415 V AC (per IEC 60947-2) gives the headroom needed for industrial panel coordination studies. ## Breaking capacity and dual-standard rating This breaker carries two breaking-capacity ratings: 6 kA Icn under EN/IEC 60898-1 (the standard for household and similar installations) and 10 kA Icu under IEC 60947-2 (the industrial standard). The C-curve (5–10 × In) suits mixed loads with moderate inrush, such as lighting banks, small motor groups, and general socket circuits. Clip-on mount to DIN rail, occupies 6 × 9 mm pitches (54 mm wide). Tunnel terminals accept 0.33–10 mm² flexible or 0.75–16 mm² rigid on both upstream and downstream sides. IP20 finger-safe terminals. ON/OFF toggle indication. Separate earth-leakage block available as an add-on. Pollution degree 3, tropicalisation class 2 per IEC 60068-1 — suitable for humid, non-condensing environments up to 95 % RH at 55 °C.","metaTitle":"Schneider Electric A9N21390 DT40N MCB, 40 A, 3P, C-Curve, 6","metaDescription":"Schneider Electric A9N21390 DT40N miniature circuit breaker, 40 A, 3-pole, C-curve, 6 kA Icn / 10 kA Icu. Active production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["Miniature Circuit Breakers (MCB)"],"specifications":{"Depth":"78 mm","Range":"Prodis","Width":"54 mm","Colour":"White","Height":"81 mm","Standards":"EN/IEC 60898-1 EN/IEC 60947-2","Curve code":"C","9 Mm Pitches":"6","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","Pollution degree":"3 conforming to IEC 60947-2","Range of product":"ProDis","Breaking capacity":"6000 A Icn at 400 V AC 50 Hz conforming to EN/IEC 60898-1 10 kA Icu at 400...415 V AC 50 Hz conforming to IEC 60947-2","Device short name":"DT40N","Network frequency":"50 Hz","Poles description":"3P","Relative humidity":"95 % at 55 °C","Tightening torque":"2 N.m","Device application":"Distribution","Operating altitude":"2000 m","[In] rated current":"40 A","Trip unit technology":"Thermal-magnetic","Electrical durability":"10000 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":"5...10 x In","Earth-leakage protection":"Separate block","Number of protected poles":"3","Product or component type":"Miniature circuit-breaker","Suitability for isolation":"Yes","Contact position indicator":"Yes","Locking options description":"Padlocking device","[Ui] rated insulation voltage":"440 V AC 50 Hz","[Ue] rated operational voltage":"400 V AC 50 Hz between phases","Ambient air temperature for storage":"-40...70 °C","Ambient air temperature for operation":"-25...70 °C","[Ics] rated service breaking capacity":"6000 A 100 % x Icn at 400 V AC 50 Hz conforming to EN/IEC 60898-1 7.5 kA 75 % x Icu at 400 V AC 50 Hz conforming to IEC 60947-2","[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/194956b90c7f03f521fb8ec9f3918630.pdf","sourceUrl":"https://www.se.com/uk/en/product/A9N21390/dt40-circuit-breaker-dt40n-3p-40a-c-curve/","alternativesUrl":"https://aoctrl.com/api/mcp/products/A9N21390/alternatives.json"},"ai":{"faq":[{"question":"How do I get current pricing and availability for A9N21390?","answer":"Submit an RFQ through this listing. Pricing and stock are confirmed at quote time through the authorized Schneider Electric channel."},{"question":"What is the breaking capacity of A9N21390?","answer":"6 kA Icn at 400 V AC per EN/IEC 60898-1 and 10 kA Icu at 400–415 V AC per IEC 60947-2."},{"question":"What compliance documentation does Schneider provide for A9N21390?","answer":"The breaker is certified to EN/IEC 60898-1 and EN/IEC 60947-2, carries NF quality label, and meets tropicalisation class 2 per IEC 60068-1 and pollution degree 3 per IEC 60947-2."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/schneider/A9N21390","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/A9N21390 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}}