{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SL4320-8","brand":"Siemens","brandSlug":"siemens","productSlug":"5SL4320-8","canonicalUrl":"https://aoctrl.com/siemens/5SL4320-8","factsUrl":"https://aoctrl.com/api/mcp/products/5SL4320-8","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SL4320-8, miniature circuit breaker, 3-pole, D tripping characteristic, 20 A, 400 V AC, 10 kA breaking capacity, 3 MW units.","salesMarkdown":"## Siemens SENTRON 5SL4320-8 — 3-pole D-curve MCB at 20 A The Siemens 5SL4320-8 is a SENTRON miniature circuit breaker rated 20 A at 400 V AC, 3-pole, with a D tripping characteristic and a 10 kA breaking capacity per both EN 60898 and IEC 60947-2. The D-curve means it tolerates the high inrush currents typical of motor and transformer loads — the magnetic trip threshold sits between 10× and 20× rated current, so it won't nuisance-trip on a compressor or conveyor start. That 10 kA SCCR at 400 V AC is the fault-clearing capability the breaker guarantees; if the available fault current at the panel exceeds that, you need an upstream current-limiting device or a higher-rated breaker. ## Thermal derating and panel fit The 20 A rating holds at 30 °C ambient. At 40 °C it derates to 18.48 A; at 45 °C to 17.6 A; at 55 °C to 15.92 A. If the enclosure runs warm — say a packed panel with drives — size the branch circuit for the actual ambient, not the nameplate. The breaker occupies 3 modular width units (54 mm total) and installs on a DIN rail; mounting position is any, so vertical or horizontal busbars are fine. Depth is 76 mm (70 mm installation depth), which fits standard 80 mm deep enclosures. IP20 with connected conductors — adequate for inside a locked panel, not for washdown. ## Power loss and environmental specs Per-pole power loss at rated current in hot operating state is 1.6 W — three poles total 4.8 W dissipated inside the enclosure. That is low enough that no forced cooling is needed in a standard steel enclosure, but worth noting if the panel is densely packed. The breaker is halogen-free and silicon-free, which matters for outgassing-sensitive environments (clean rooms, semiconductor fabs). Operating temperature range is -40 °C to 75 °C; storage range is the same. Overvoltage category III, pollution degree 2 — standard for fixed-installation distribution boards.","metaTitle":"Siemens 5SL4320-8 SENTRON MCB, 3P D 20A 400V 10kA","metaDescription":"Siemens SENTRON 5SL4320-8 miniature circuit breaker, 3-pole, D-curve, 20 A, 400 V AC, 10 kA breaking capacity per EN 60898/IEC 60947-2. Active production. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["3-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Width":"54 mm","title":"5SL4320-8","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","description":"Miniature circuit breaker 400 V 10kA, 3-pole, D, 20 A","Halogen-Free":"Yes","Silicon-Free":"Yes","Design Of Pole":"3P","Number Of Poles":"3","lifecycle_stage":"current","Mounting Position":"any","at AC rated value":"20 A","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"2","Product Designation":"Miniature circuit breaker","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","at 30 °C rated value":"20 A","at 40 °C rated value":"18.48 A","at 45 °C rated value":"17.6 A","at 55 °C rated value":"15.92 A","Energy Limitation Class":"3","Suitability For Operation":"Residential buildings/infrastructure","at DC rated value maximum":"72 V","Number Of Modular Width Units":"3","Tripping Characteristic Class":"D","supply voltage at AC rated value":"400 V","according to EN 60898 rated value":"10 kA","according to IEC 60947-2 rated value":"10 kA","Type Of Voltage Of The Operating Voltage":"AC","with multi-phase operation at AC maximum":"440 V","Value Range Of The Supply Voltage Frequency":"50/60 Hz","with multi-phase operation at AC rated value":"440 V","Mechanical Service Life (Operating Cycles) Typical":"10 000","Product Extension Installable Supplementary Devices":"Yes","power loss [W] for rated value of the current at AC in hot operating state per pole":"1.6 W"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/b97409499536e89ee77516dc7ad97276.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=348526&mlfb=5SL4320-8"},"ai":{"faq":[{"question":"What is the breaking capacity of the 5SL4320-8?","answer":"10 kA per both EN 60898 and IEC 60947-2 at 400 V AC."},{"question":"What does the D-curve mean on this breaker?","answer":"The D tripping characteristic has a magnetic trip threshold between 10× and 20× In, so it is designed for loads with high inrush current such as motors, transformers, and welding equipment."},{"question":"Where can I buy the 5SL4320-8 and how is it quoted?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"Will the 5SL4320-8 fit in a panel specified for the 5SL4363-7?","answer":"Both are 3-pole SENTRON MCBs in the same 3 MW unit footprint (54 mm wide), so the 5SL4320-8 drops into the same DIN-rail position without rewiring. The difference is the rating: the 5SL4320-8 is a 20 A D-curve; the 5SL4363-7 is a 63 A D-curve."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SL4320-8","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/5SL4320-8 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}}