The SENTRON 5SQ2170-0KA15 is a 1-pole miniature circuit breaker rated 15 A at 240 V AC, with a C tripping characteristic and a 3 kA breaking capacity verified to EN 60898. The C-curve means it trips between 5 and 10 times rated current, so it handles moderate inrush from small motor or lighting loads without nuisance tripping, but clears a hard short fast enough for the 3 kA fault level.
No neutral pole to switch; this is a line-side only break.
The 3 kA breaking capacity per EN 60898 is the rated short-circuit capacity for this MCB at 240 V AC — it will safely interrupt a fault current up to 3 kA without welding contacts or cascading failure upstream. The overvoltage category 3 rating means it's suitable for fixed-installation distribution boards, not just final circuits. Energy limiting class 3 indicates it restricts let-through energy during a fault, which helps with downstream coordination.