Ratings & fit notes
The 5SY4204-5: The A-characteristic is uncommon in distribution MCBs – most are B, C, or D. Here, the magnetic release kicks in at 2–3x In, so this breaker clears fast on low-level shorts. At 40 °C ambient the continuous current derates to 3.76 A, at 50 °C to 3.5 A, and at 60 °C to 3.22 A – factor that into your panel thermal budget to avoid nuisance tripping. Physical fit: 36 mm wide (2 modular units), 76 mm deep, 70 mm installation depth behind the panel. Mounts in any position, IP20 with connected conductors. Sealable for metering or tamper-proof circuits. Halogen-free and silicon-free construction – clean for sensitive environments like labs or food processing. Combined terminals top and bottom accept the same wire types – no separate feed-through lug needed. Rated for pollution degree 3, overvoltage category III, so it lives in industrial panels without derating for dirt or switching surges.