What this 4-pole C-curve 0.3 A MCB does for a panel
Rated 0.3 A at 400 V AC with a C tripping characteristic, it opens on a magnetic trip between 5 and 10 times rated current — meaning it's sized for protecting a lightly loaded control circuit or a small transformer secondary, not a motor feeder.
Panel fit and wiring constraints
Terminal capacity accepts 0.75 to 25 mm² solid or stranded copper; the screw terminals call for a tightening torque of 2.5 to 3 N·m.
The breaker is rated for overvoltage category 3 and carries an energy limiting class of 3. It's halogen-free and silicon-free, sealable, and includes touch protection on the terminals. The product is designed for residential buildings and infrastructure applications per the manufacturer's suitability listing.