The Siemens 5SU9326-7CR16 is a 1P+N residual current circuit breaker with overcurrent protection (RCBO) rated 16 A, 230 V AC, with a 6 kA breaking capacity. Type A residual current detection (30 mA) covers pulsating DC faults from rectified loads like VFDs, LED drivers, and switched-mode supplies, which a plain AC type would miss.
Snap-on DIN rail mounting per EN 60715. The 1P+N module occupies a single 18 mm width — tight for a crowded enclosure, but leaves room for supplementary surge arrestors or isolators on the same rail.