The Siemens 5SU1153-1KV13 is a combined residual-current device and miniature circuit breaker (RCBO) — an FI/LS protector in Siemens' catalog. It packs both earth-leakage and overcurrent protection into a single 1+N-pole module. The C 13A overcurrent characteristic handles moderate inrush loads (motors, transformers, lighting banks) without nuisance tripping, while the 4.5 kA breaking capacity at 230/400 V is the standard domestic and light-commercial rating under IEC 60898. The 70 mm width (D=70mm) is the standard 4-module DIN-rail footprint — it occupies four 17.5 mm slots in the panel.
Deployment context
The 10 mA trip sensitivity makes it a natural fit for circuits serving shower rooms, outdoor sockets, or industrial wash-down areas where the earth-leakage threshold needs to be lower than the typical 30 mA. The Type AC waveform detection covers the majority of residential and commercial installations, but note it will not reliably trip on pulsating DC or smooth DC fault currents — that would call for a Type A or Type F device.