{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY5120-7CC11","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY5120-7CC11","canonicalUrl":"https://aoctrl.com/siemens/5SY5120-7CC11","factsUrl":"https://aoctrl.com/api/mcp/products/5SY5120-7CC11","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY5120-7CC11, miniature circuit breaker, 1-pole, C-curve, 20 A, 10 kA DC at 220 V, for railway applications.","salesMarkdown":"The Siemens SENTRON 5SY5120-7CC11 is a 1-pole miniature circuit breaker rated 20 A with a C tripping characteristic, designed specifically for DC circuits up to 250 V and carrying a 10 kA breaking capacity at 220 V DC per IEC 60947-2. This is not a general-purpose AC-only MCB — the DC rating and the railway designation mean it is built for the vibration profile, temperature extremes, and polarity-aware wiring of rail applications. The 18 mm width (1 MW) fits standard DIN-rail distribution boards, and the quick-assembly fastening system lets it snap into place without tools. ## What the DC rating means for your circuit DC arcs are harder to extinguish than AC arcs because there is no natural zero-crossing. The 5SY5120-7CC11 is tested to IEC 60947-2 for DC interruption, achieving 10 kA at 220 V DC. That 10 kA figure is the prospective short-circuit current it can safely break — if your DC bus can deliver more fault current (e.g., a large battery bank or rectified supply), you need to verify coordination upstream. The C-curve means magnetic trip occurs at 5 to 10 times rated current, so a 20 A breaker trips magnetically between 100 A and 200 A. That suits moderate inrush loads like DC contactor coils, solenoids, or control transformers, but not highly capacitive loads that might cause nuisance trips.","metaTitle":"Siemens 5SY5120-7CC11 SENTRON MCB, 1P C 20A DC Railway","metaDescription":"Siemens SENTRON 5SY5120-7CC11 miniature circuit breaker, 1-pole C-curve 20A, 10kA DC breaking capacity at 220V. Rated for railway applications. 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","Width":"18 mm","title":"5SY5120-7CC11","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","description":"Circuit breaker Universal current 220 V DC 230/400 V AC 10kA, 1-pole, C, 20A for railway applications","Halogen-Free":"Yes","Silicon-Free":"Yes","Design Of Pole":"1P","Number Of Poles":"1","lifecycle_stage":"current","Fastening Method":"Quick assembly system","Mounting Position":"any","at DC rated value":"220 V","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"3","Product Designation":"Miniature circuit breaker","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"Yes","Design Of The Product":"For railway applications","Combined Terminal Bottom":"Yes","Suitability For Operation":"Railway","Neutral Conductor Switching":"No","Number Of Modular Width Units":"1","Position Of Power Supply Cord":"Consider polarity","Tripping Characteristic Class":"C","Influence Of The Surrounding Temperature":"max. 95% to 55°C, max. 55% to 70°C, max. 35% to 75°C","Type Of Voltage Of The Operating Voltage":"DC","at DC according to IEC 60947-2 rated value":"10 kA","operating voltage at DC rated value maximum":"250 V","vibration resistance according to IEC 60068-2-6":"±1mm at 5 to 25Hz; 50m/s² at 25 to 150Hz","Product Extension Installable Supplementary Devices":"Yes"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/67107c8a83fa0ecf344e41ada174b119.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=146382&mlfb=5SY5120-7CC11"},"ai":{"faq":[{"question":"Where can I buy 5SY5120-7CC11 and what is the lead time?","answer":"The 5SY5120-7CC11 is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — no stock count or lead-time figure is published here."},{"question":"What compliance documentation is available for 5SY5120-7CC11?","answer":"The breaker is designed to IEC 60947-2 for DC interruption. It is halogen-free and silicon-free, which supports rail fire-safety and outgassing requirements. The SENTRON series typically carries CE, UL, and CSA certifications, but specific documentation should be confirmed at order time."},{"question":"What is the width and depth of 5SY5120-7CC11?","answer":"The 5SY5120-7CC11 has a width of 18 mm (1 modular width), a height of 90 mm, a depth of 76 mm, and an installation depth of 70 mm."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY5120-7CC11","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/5SY5120-7CC11 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}}