The Siemens 5SJ4163-8HG40 is a 1-pole SENTRON miniature circuit breaker with a D tripping characteristic, rated 400 V AC and 60 V DC. It carries a 10 kA breaking capacity per EN 60898 and 15 kA per IEC 60947-2, sized for motor-starting and high-inrush loads in industrial control panels.
What the ratings mean for fit
The D curve (10–20× In) is the key selector here — it avoids nuisance tripping on transformer inrush or motor start, unlike a B or C curve that would drop out on the same surge. The 15 kA SCCR under IEC 60947-2 gives headroom for high-fault industrial mains; the 10 kA EN 60898 rating covers residential/commercial distribution boards. Single-pole design (1 MW width) fits standard 18 mm DIN-rail slots, and the mounting position is any orientation.