Siemens 5SL4163-6CC Miniature Circuit Breaker, 1-Pole B 63 A

The Siemens 5SL4163-6CC is a 1-pole miniature circuit breaker (MCB) with a B-curve trip characteristic, rated 63 A and a breaking capacity of 10 kA at 230/400 V. This is the standard MCB for protecting branch circuits in residential and light commercial distribution boards — the B-curve trips between 3 and 5 times rated current, so it's sized for resistive and general-purpose loads where inrush is moderate. The 10 kA short-circuit capacity is sufficient for most domestic and small commercial service entrances where the prospective fault current stays under that level.