{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY5125-6KK11","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY5125-6KK11","canonicalUrl":"https://aoctrl.com/siemens/5SY5125-6KK11","factsUrl":"https://aoctrl.com/api/mcp/products/5SY5125-6KK11","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY5125-6KK11, 1-pole miniature circuit breaker, B-curve, 25 A rated current, 10 kA breaking capacity at 400 V AC, 18 mm width, IP20.","salesMarkdown":"## Siemens 5SY5125-6KK11 — 1P B-Curve MCB, 25 A, 10 kA, Railway-Rated The Siemens 5SY5125-6KK11 is a 1-pole SENTRON miniature circuit breaker with a B-curve tripping characteristic, rated 25 A at 400 V AC and 10 kA breaking capacity per EN 60898. It also carries a DC rating of 220 V with 10 kA interrupting capacity per EN 60898-2, making it suitable for mixed AC/DC control circuits in a single enclosure. Rated for universal current operation (AC/DC), this breaker handles both power and control loads without derating the trip curve — a practical advantage when the same rail feeds a 24 VDC relay bank and a 230 VAC contactor coil. The 25 A B-curve trips between 3× and 5× rated current (75–125 A magnetic release), so it protects lighting, control transformers, and general-purpose circuits where inrush is moderate. Energy limiting class 3 means the breaker clears a fault fast enough to limit let-through energy, reducing thermal stress on downstream wiring and connected equipment. This is one of the highest energy-limiting classes per IEC standards. The 18 mm width (1 width unit) fits standard DIN-rail enclosures. The quick-assembly mounting system clips onto standard DIN rail without tools.","metaTitle":"Siemens 5SY5125-6KK11 SENTRON MCB, 1P B-Curve 25 A, 10 kA","metaDescription":"Siemens 5SY5125-6KK11 SENTRON miniature circuit breaker, 1-pole, B-curve, 25 A rated, 10 kA breaking capacity at 400 V AC. Active production, sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["1-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Solid":"0.75 ... 35 mm²","Width":"18 mm","Height":"90 mm","Sealable":"Yes","Stranded":"0.75 ... 35 mm²","Rated Value":"50/60 Hz","Halogen-Free":"Yes","Silicon-Free":"Yes","Mounting type":"Quick assembly system","During Storage":"-40 ... +75 °C","Number of poles":"1","Type of voltage":"AC/DC","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Ambient temperature":"-40 ... +70 °C","Product designation":"Miniature circuit breaker","Protection class IP":"IP20, with connected conductors","at AC / rated value":"400 V","at DC / rated value":"220 V","Overvoltage category":"III","Combined Terminal Top":"Yes","Design of the product":"For railway applications","Energy limiting class":"3","Number of width units":"1","Number of poles / Note":"1P","acc. to DIN EN 61346-2":"F","acc. to DIN EN 81346-2":"F","Combined Terminal Bottom":"Yes","Suitability for operation":"universal current","at DC / acc. to EN 60898-2":"10 kA","Current / at AC / rated value":"25 A","Tripping characteristic class":"B","at DC / rated value / maximum":"250 V","acc. to EN 60898 / rated value":"10 kA","Position / of power supply cord":"AC as required, observe DC polarity","Product feature / Touch protection":"Yes","Influence of the surrounding temperature":"max. 95% to 55°C, max. 55% to 70°C, max. 35% to 75°C","at DC / acc. to IEC 60947-2 / rated value":"15 kA","Tightening torque / with screw-type terminals":"2.5 ... 3.5 N·m","Product function / neutral conductor switching":"No","with multi-phase operation / at AC / rated value":"440 V","with single-phase operation / at AC / rated value":"440 V","Mechanical service life (switching cycles) / typical":"10 000","Tightening torque [lbf·in] / with screw-type terminals":"22 ... 31 lbf·in","AWG number / as coded connectable conductor cross section":"18 ... 4"}},"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=285756&mlfb=5SY5125-6KK11","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY5125-6KK11/alternatives.json"},"ai":{"faq":[{"question":"What is the breaking capacity of the 5SY5125-6KK11?","answer":"The 5SY5125-6KK11 has a 10 kA breaking capacity at 400 V AC per EN 60898, and 10 kA at 220 V DC per EN 60898-2."},{"question":"Where can I buy the 5SY5125-6KK11 and what is the lead time?","answer":"The 5SY5125-6KK11 is sourced and quoted to order against an RFQ through our independent distribution channel. Availability and current pricing are confirmed at the time of quote — submit an RFQ for a firm lead time."},{"question":"Will the 5SY5125-6KK11 fit in a panel designed for the 5SY3132-6?","answer":"Both are 1-pole SENTRON MCBs with the same 18 mm width and DIN-rail mounting, so the 5SY5125-6KK11 will physically drop into the same panel position. However, the 5SY3132-6 is a C-curve 32 A breaker; verify your circuit's fault-current rating and trip coordination before swapping — the B-curve trips faster on moderate overloads, which may affect selectivity with downstream devices."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY5125-6KK11","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/5SY5125-6KK11 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}}