The Siemens 5SU1156-1KV13 is a combined residual-current device and miniature circuit breaker (RCBO) — an FI/LS protector Type AC with a 10 mA rated residual current, 6 kA breaking capacity, 1+N-pole configuration, and C-curve 13 A overcurrent characteristic.
Rated for Type AC residual currents — meaning it detects sinusoidal AC faults only, not pulsating DC or smooth DC. The 10 mA IΔN is the sensitivity for personnel protection in wet or medical locations where standard 30 mA units are too coarse.