Caparoc is a modular and expandable system, consisting of power and circuit breaker modules as well as current rails of different lengths, for selective protection and power distribution of the 24 V power supply. The new innovative supply of the system via the current rail at the rear of the system enables a continuous and uninterruptible supply of all modules. This has the advantage that later extensions can be carried out during operation without affecting the existing structure or switching off the system. Additional current rails are simply plugged into the system and further circuit breaker modules are snapped on. Caparoc‘s electronic circuit breaker modules automatically connect to the power module when snapped on. For the user, this means that the system is ready for immediate operation. The Profinet interface also makes the status of the 24 V supply completely transparent, right down to the flowing current.