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 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.