SENTRON 5SL4203-8CC — D-curve 3 A, 2-pole MCB
The D-curve means it tolerates inrush spikes typical of motor and transformer loads — expect it to hold through a 10× to 20× rated-current surge for a short duration, so it's a fit for small motor branch circuits or lighting with heavy ballast inrush.
Where it lands in a panel
Installation depth is 70 mm, meaning the body extends that far behind the rail; verify your enclosure depth clearance if you're retrofitting into a shallow box.
Thermal derating and environmental range
At 40 °C it derates to 2.88 A, at 50 °C to 2.75 A, and at 55 °C to 2.69 A. Pollution degree 2 (normal industrial, non-condensing) and overvoltage category III (distribution-level transients) are standard for this class.
Rated per EN 60898 (the household/residential MCB standard). The breaker is sealable, halogen-free, and silicon-free — useful for environments sensitive to outgassing, like clean rooms or sealed enclosures. Touch protection is built in (finger-safe terminals when wired).