{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SP3440-3","brand":"Siemens","brandSlug":"siemens","productSlug":"5SP3440-3","canonicalUrl":"https://aoctrl.com/siemens/5SP3440-3","factsUrl":"https://aoctrl.com/api/mcp/products/5SP3440-3","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SP3440-3, main miniature circuit breaker, 4-pole (4P), rated 40 A at 30 °C, tripping characteristic E, 25 kA breaking capacity per EN 60898 at 400 V AC, 6 MW units, depth 76.3 mm.","salesMarkdown":"## What this 5SP3440-3 is The Siemens 5SP3440-3 is a SENTRON main miniature circuit breaker (MCB) in a 4-pole (4P) configuration, rated 40 A at 30 °C and carrying a tripping characteristic E — a curve designed for protection of circuits with high inrush currents, such as motor starters or transformer primaries, where a standard B or C curve would nuisance-trip on startup. Its rated breaking capacity is 25 kA per EN 60898 at 400 V AC, with an insulation voltage of 690 V and overvoltage category IV — meaning it can safely interrupt fault currents up to 25 kA in a 400 V three-phase network, and is rated for the highest overvoltage stress at the service entrance. Characteristic E is the least common of the standard MCB curves, sitting between C (5–10× In) and D (10–20× In). It typically trips at 10–20× rated current, so a 40 A E-curve breaker will hold through the magnetizing inrush of a 30 kVA transformer or a large contactor coil pull-in, while still providing short-circuit protection. This makes the 5SP3440-3 a better fit for industrial sub-distribution or infrastructure panels than for general-purpose socket circuits — the E curve avoids nuisance trips on motorized loads that a C-curve might not handle. The 4-pole body occupies 6 modular width units (MW). Conductor cross-section: solid or stranded from 2.5 mm² up to 50 mm², with saddle terminals and infeed at box terminal — so it accepts large incoming cables without piggyback lugs. IP40 with connected conductors, pollution degree 3 (industrial environment with conductive dust), shock resistance 30 g for 11 ms impacts. Ambient temperature range -40 °C to +70 °C, with derated current at elevated temperatures: 38 A at 40 °C, 36 A at 50 °C, 35 A at 55 °C. ## Locking and sealing Integrated locking slide accepts a padlock, wire seal, or cable ties — sealable for safety isolation verification. The part is also sealable per the spec, and the supply cord position is any (top or bottom feed).","metaTitle":"Siemens 5SP3440-3 SENTRON MCB, 4P, 40A, E-Characteristic, 25","metaDescription":"Siemens 5SP3440-3 SENTRON miniature circuit breaker, 4-pole, 40 A rated, tripping characteristic E, 25 kA breaking capacity at 400 V AC. Active production. Sourced to order against","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["4-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76.3 mm","title":"5SP3440-3","Height":"128 mm","Maximum":"70 °C","Minimum":"-40 °C","Sealable":"Yes","Rated Value":"25 kA","description":"Main miniature circuit breaker (SHU), 4-pole, E 40, 400V","Number Of Poles":"4","Solid / Maximum":"50 mm²","Solid / Minimum":"2.5 mm²","lifecycle_stage":"current","Fastening Method":"standard rail","Saddle Terminals":"Yes","Shock Resistance":"30 g, at least 3 impacts, impact duration 11 ms","Product Brand Name":"SENTRON","Stranded / Maximum":"50 mm²","Stranded / Minimum":"2.5 mm²","Degree Of Pollution":"3","Product Designation":"Miniature circuit breaker","acc. to IEC 81346-2":"F","at AC / rated value":"40 A","protection class IP":"IP40, with connected conductors","Overvoltage Category":"IV","Design Of The Product":"Main miniature circuit breaker","Infeed At Box Terminal":"Yes","Number Of Poles / Note":"4P","acc. to DIN EN 61346-2":"F","at 30 °C / rated value":"40 A","at 40 °C / rated value":"38 A","at 45 °C / rated value":"37 A","at 50 °C / rated value":"36 A","at 55 °C / rated value":"35 A","Depth / Of The Enclosure":"76.3 mm","Suitability For Operation":"Residential buildings/infrastructure","Design Of The Locking Device":"Integrated locking slide, lockable by means of a lock, wire seal and cable ties","Number Of Modular Width Units":"6","Tripping Characteristic Class":"E","acc. to EN 60898 / rated value":"25 kA","Position / Of Power Supply Cord":"Any","Insulation Voltage / Rated Value":"690 V","supply voltage / at AC / rated value":"400 V","Surge Voltage Resistance / Rated Value":"6 kV","Fastening Method / Other Installation / Note":"On standard mounting rail 35 mm acc. to EN 60715","vibration resistance / acc. to IEC 60068-2-6":"2 g, 20 frequency cycles 5 to 150 to 15 Hz","Display Version / For Switch Position Indicator":"OFF = green, ON = red","Mechanical Service Life (Operating Cycles) / Typical":"20 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/420987aca3d5ce17971af369ecad550b.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=157563&mlfb=5SP3440-3"},"ai":{"faq":[{"question":"What is 5SP3440-3 used for?","answer":"This SENTRON miniature circuit breaker with E characteristic is suited for residential and infrastructure applications where high inrush currents from transformers or motor starters are present — it protects branch circuits in main distribution panels."},{"question":"What is the breaking capacity of 5SP3440-3?","answer":"The rated breaking capacity is 25 kA per EN 60898 at 400 V AC, with an insulation voltage of 690 V and overvoltage category IV."},{"question":"Where can I buy 5SP3440-3?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution — availability and current pricing are confirmed at quote time."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SP3440-3","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/5SP3440-3 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}}