{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SP4240-6","brand":"Siemens","brandSlug":"siemens","productSlug":"5SP4240-6","canonicalUrl":"https://aoctrl.com/siemens/5SP4240-6","factsUrl":"https://aoctrl.com/api/mcp/products/5SP4240-6","rawCanonicalId":null},"summary":{"shortDescription":"SENTRON 5SP Miniature Circuit Breaker, 5SP4 design, 2-pole, B-curve, 40 A, 10 kA (EN 60898) / 20 kA (IEC 60947-2) at 400 V AC, tunnel terminals top and bottom, 70 mm installation depth.","salesMarkdown":"It breaks fault currents up to 10 kA per EN 60898 and 20 kA per IEC 60947-2 at 400 V AC — the higher IEC figure gives you headroom for industrial panel coordination where the upstream transformer can deliver more fault current than a residential service. Tunnel terminals on both top and bottom accept conductors without needing ring lugs, which speeds up panel wiring. The 70 mm installation depth matches the standard SENTRON 5SP footprint, so it clips onto the same DIN rail as other 5SP units without protruding past the enclosure door. ## What the B-curve and 40 A rating mean for your circuit The B-curve trips magnetically between 3 and 5 times rated current (120–200 A for this 40 A unit). That makes it a good fit for resistive or lighting loads with low inrush — think heater banks, incandescent strips, or general-purpose socket circuits. For motor or transformer starts that draw 6–10× rated current momentarily, a C-curve sibling would be the better call to avoid nuisance tripping. ## Panel fit and approvals The 2-pole body occupies two modular width units (36 mm), leaving room alongside other 5SP breakers for a clean, ganged layout. The 10 kA rating under EN 60898 satisfies most building-distribution requirements; the 20 kA rating under IEC 60947-2 covers industrial panels where higher fault levels are expected.","metaTitle":"SENTRON 5SP4240-6 Miniature Circuit Breaker, 2P, B, 40A","metaDescription":"SENTRON 5SP4240-6 miniature circuit breaker, 2-pole, B-curve, 40 A, 10 kA (EN 60898) / 20 kA (IEC 60947-2) at 400 V AC. Current lifecycle stage. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["2-Pole MCB (DIN Rail)"],"specifications":{"Number of poles":"2","lifecycle_stage":"current","Installation depth":"70 mm","Product brand name":"SENTRON","Product designation":"Miniature circuit breaker","Tunnel terminals top":"Yes","Design of the product":"5SP Miniature circuit breakers","Number of poles / Note":"2P","Tunnel terminals bottom":"Yes","circuit-breaker / Design":"5SP4","Current / at AC / rated value":"40 A","Tripping characteristic class":"B","acc. to EN 60898 / rated value":"10 kA","acc. to IEC 60947-2 / rated value":"20 kA","Supply voltage / at AC / rated value":"400 V"}},"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=354292&mlfb=5SP4240-6","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SP4240-6/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of 5SP4240-6?","answer":"It has a 10 kA breaking capacity per EN 60898 and a 20 kA breaking capacity per IEC 60947-2 at 400 V AC."},{"question":"Where can I buy 5SP4240-6?","answer":"We source this part to order against an RFQ — send your quantity and we'll confirm availability and current pricing at quote time."},{"question":"What is the difference between 5SP4240-6 and 5SP4292-7?","answer":"The main difference is the tripping characteristic: 5SP4240-6 uses a B-curve (3–5× In magnetic trip) while 5SP4292-7 uses a C-curve (5–10× In). Both are 2-pole, 40 A SENTRON 5SP breakers with the same 70 mm depth and tunnel terminals, so they share the same physical footprint and DIN-rail mounting. Choose the B-curve for resistive loads and the C-curve for motor or transformer circuits with higher inrush."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SP4240-6","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/5SP4240-6 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}}