The Siemens 5SU1654-0KV13 is a combined residual-current and miniature circuit breaker (RCBO) — an FI/LS protector — in a 1+N-pole format. It integrates Type AC residual-current detection at 300 mA with a B-curve overcurrent trip rated 13 A, all in a 70 mm-wide housing. The 10 kA breaking capacity means it can safely interrupt fault currents up to that level without upstream damage, sized for final subcircuits in TN and TT systems where both earth-leakage and short-circuit protection are needed in one DIN-rail module.
The 300 mA residual sensitivity (Type AC) suits it for general-purpose circuits where sinusoidal AC earth-leakage is the concern — lighting, socket outlets, small loads — rather than pulsating DC or mixed-frequency leakage from VFDs or switched-mode supplies. The B-curve at 13 A means the magnetic trip operates between 3 and 5 times rated current (39–65 A), typical for resistive and lightly inductive loads where inrush is moderate. The 70 mm width (roughly 4 module spaces on a DIN rail) is wider than a standard single-pole MCB; factor that into enclosure fill calculations.