{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"5SY3203-7","brand":"Siemens","brandSlug":"siemens","productSlug":"5SY3203-7","canonicalUrl":"https://aoctrl.com/siemens/5SY3203-7","factsUrl":"https://aoctrl.com/api/mcp/products/5SY3203-7","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON 5SY3 series, 5SY3203-7 miniature circuit breaker, 2-pole, C tripping characteristic, 3 A rated current at 400 V AC, 4.5 kA per EN 60898.","salesMarkdown":"## Siemens 5SY3203-7 — 2-pole C-curve MCB for 3 A branch circuits The Siemens 5SY3203-7 is a 2-pole miniature circuit breaker from the SENTRON 5SY3 series, rated 3 A at 400 V AC with a C tripping characteristic. At 3 A it handles branch circuits feeding control transformers, contactor coils, or signal-conditioning supplies in a panel. Breaking capacity is rated at 4.5 kA per EN 60898 and 6 kA per IEC 60947-2 at 400 V AC; for DC circuits it's rated 15 kA at 72 V DC per IEC 60947-2, and 5 kA at 400 V AC per UL 1077 / CSA C22.2 No.235. That covers most industrial panel fault currents below a main distribution board. No last-time-buy or phase-out notice is on record. For BOM-freeze planning, the 5SY3 series has broad installed base and the form factor (2-module wide, DIN-rail mount) is industry-standard, so any future replacement would share the same footprint. Combined top and bottom terminals accept solid or stranded conductors from 0.75 mm² up to 35 mm² — a wide range that covers both control-circuit wiring (1.5 mm²) and feeder tails (10–16 mm²). The terminals are touch-protected (IP20 with conductors connected) and sealable for panel lock-out/tag-out procedures. ## Coordination and selectivity note Energy limiting class 3 means the breaker limits let-through energy well — useful for downstream component protection. Overvoltage category III suits fixed-installation distribution boards. The 5SY3 design is the standard 5SY platform with C-curve; the 5SY6 series (higher breaking capacity) exists for applications needing more fault-current headroom, but the 5SY3203-7 covers the common 3 A branch with adequate interrupting ratings for most sub-distribution panels.","metaTitle":"Siemens 5SY3203-7 SENTRON MCB, 2P C-Curve 3A 4.5kA","metaDescription":"Siemens 5SY3203-7 SENTRON miniature circuit breaker, 2-pole, C-curve, 3 A rated, 4.5 kA breaking capacity per EN 60898. Active production, sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":null,"categoryPath":["2-Pole MCB (DIN Rail)"],"specifications":{"Depth":"76 mm","Solid":"0.75 ... 35 mm²","Width":"36 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":"2","Type of voltage":"AC","lifecycle_stage":"current","Mounting position":"any","Installation depth":"70 mm","Product brand name":"SENTRON","Ambient temperature":"-25 ... +55 °C","Product designation":"Miniature circuit breaker","Protection class IP":"IP20, with connected conductors","at AC / rated value":"400 V","Overvoltage category":"III","Combined Terminal Top":"Yes","Energy limiting class":"3","Number of width units":"2","Number of poles / Note":"2P","acc. to DIN EN 61346-2":"F","acc. to DIN EN 81346-2":"F","Combined Terminal Bottom":"Yes","circuit-breaker / Design":"5SY3","Current / at AC / rated value":"3 A","Tripping characteristic class":"C","at DC / rated value / maximum":"72 V","acc. to EN 60898 / rated value":"4.5 kA","Position / of power supply cord":"Any","acc. to IEC 60947-2 / rated value":"6 kA","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","at AC / acc. to UL 1077 and CSA C22.2 No.235":"5 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","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=226229&mlfb=5SY3203-7","alternativesUrl":"https://aoctrl.com/api/mcp/products/5SY3203-7/alternatives.json"},"ai":{"faq":[{"question":"What wire sizes does the 5SY3203-7 terminal accept?","answer":"Both solid and stranded conductors from 0.75 mm² up to 35 mm². The terminals are combined (top and bottom) and touch-protected."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/5SY3203-7","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/5SY3203-7 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}}