The Siemens 5SU9353-7CN10 is a combined residual current device and miniature circuit breaker (RCBO) from the SENTRON family, integrating overcurrent and earth-leakage protection in a single 2-module-wide unit. Type A residual-current detection catches both sinusoidal AC faults and pulsating DC fault currents — the standard requirement for single-phase electronics, variable-speed drives, and appliances with rectifier front ends. The 30 mA trip threshold provides supplementary protection against direct-contact shock in final circuits.
Panel fit and installation
Depth is 77 mm, installation depth 70 mm — confirm enclosure depth clearance, particularly in shallow consumer units or compact sub-distribution boards. Mounting position is unrestricted, and supply can enter from either top or bottom, which simplifies busbar routing.
Mechanical endurance is 10,000 switching cycles typical.