{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY4303-7CC","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY4303-7CC","canonicalUrl":"https://aoctrl.com/siemens/5SY4303-7CC","factsUrl":"https://aoctrl.com/api/mcp/products/5SY4303-7CC","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY4303-7CC, miniature circuit breaker, 3-pole, 3 A rated current, C tripping characteristic, 10 kA breaking capacity per EN 60898, 50/60 Hz AC, IP20, 3 modular width units.","salesMarkdown":"## What this MCB does and where it fits The Siemens SENTRON 5SY4303-7CC is a 3-pole miniature circuit breaker rated 3 A with a C tripping characteristic, designed to protect branch circuits in industrial control panels and mechanical engineering installations. Its 10 kA breaking capacity per EN 60898 means it can safely interrupt fault currents up to that level under standard conditions — adequate for most sub-distribution boards and machine supply circuits where the prospective short-circuit current is within that range. The C-curve trips between 5 and 10 times rated current, so it's sized for inductive loads like small contactors and relay coils that draw a moderate inrush without nuisance tripping on start-up. Mounting is on a standard DIN rail via the quick assembly system, and the breaker occupies 3 modular width units (54 mm). The mounting position is unrestricted — any orientation works — and the installation depth behind the panel is 70 mm. Pollution degree 3 and overvoltage category III ratings confirm it's suited for the industrial environment inside a cabinet where conductive dust and transient surges are expected. ## Thermal derating and real-world current The 3 A rating holds at 35 °C ambient. Above that, the thermal-magnetic trip element derates: 2.82 A at 40 °C, 2.73 A at 45 °C, 2.63 A at 50 °C, and 2.53 A at 55 °C. If the panel runs warm — common in a packed enclosure with drives or transformers — the actual continuous current the breaker can carry without tripping drops accordingly. The surrounding temperature influence spec also caps relative humidity: max 95 % up to 55 °C, then derating to 55 % at 70 °C and 35 % at 75 °C. That's a reminder that a sealed, unventilated cabinet can push internal ambient past the nominal rating point, and the breaker's load must be sized for the real temperature, not the label.","metaTitle":"Siemens 5SY4303-7CC SENTRON MCB, 3A C-Curve, 10kA, 3-Pole","metaDescription":"Siemens SENTRON 5SY4303-7CC miniature circuit breaker, 3 A, C characteristic, 10 kA breaking capacity per EN 60898, 3-pole, IP20. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["3-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Width":"54 mm","title":"5SY4303-7CC","Height":"90 mm","Maximum":"75 °C","Minimum":"-40 °C","Sealable":"Yes","description":"Miniature circuit breaker 400 V 10kA, 3-pole, C, 3 A","Halogen-Free":"Yes","Silicon-Free":"Yes","Design Of Pole":"3P","Number Of Poles":"3","lifecycle_stage":"current","Fastening Method":"Quick assembly system","Mounting Position":"any","Installation Depth":"70 mm","Product Brand Name":"SENTRON","Degree Of Pollution":"3","Product Designation":"Miniature circuit breaker","at AC / rated value":"3 A","protection class IP":"IP20, with connected conductors","Overvoltage Category":"III","Combined Terminal Top":"Yes","Energy Limitation Class":"3","according to EN 61346-2":"F","at 35 °C / rated value":"3 A","at 40 °C / rated value":"2.82 A","at 45 °C / rated value":"2.73 A","at 50 °C / rated value":"2.63 A","at 55 °C / rated value":"2.53 A","Combined Terminal Bottom":"Yes","according to IEC 81346-2":"F","Suitability For Operation":"Mechanical engineering / industry","Number Of Modular Width Units":"3","Tripping Characteristic Class":"C","Position / Of Power Supply Cord":"Any","Product Feature / Touch Protection":"Yes","according to EN 60898 / rated value":"10 kA","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":"AC","Value Range / Of The Supply Voltage Frequency":"50/60 Hz","Product Component / Neutral Conductor Switching":"No","with multi-phase operation / at AC / rated value":"440 V","operating voltage / at DC / rated value / maximum":"72 V","vibration resistance / according to IEC 60068-2-6":"±1mm at 5 to 25Hz; 50m/s² at 25 to 150Hz","with single-phase operation / at AC / rated value":"440 V","Mechanical Service Life (Switching Cycles) / Typical":"10 000"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/3becc0866aed1f5a409354064d985998.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=247439&mlfb=5SY4303-7CC"},"ai":{"faq":[{"question":"What is the breaking capacity of the 5SY4303-7CC?","answer":"10 kA rated breaking capacity per EN 60898. That's the standard industrial level for sub-distribution and machine supply circuits."},{"question":"What is the difference between the 5SY4303-7CC and the 5SY4301-7CV?","answer":"The 5SY4301-7CV is a 1-pole version of the same 3 A C-curve MCB. The 5SY4303-7CC is 3-pole, so it occupies 3 modular width units instead of 1. Otherwise the ratings — 3 A, C characteristic, 10 kA, same thermal derating curve — are identical. A panel wired for the 1-pole variant would need re-termination and more DIN rail space to swap to the 3-pole unit."},{"question":"Where can I buy the 5SY4303-7CC?","answer":"Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — submit an RFQ for a firm commitment."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY4303-7CC","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/5SY4303-7CC 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}}