The Siemens 5SU1356-6KV06 is an FI/LS combination unit — a residual-current circuit breaker with integral overcurrent protection (RCBO) in a single 1+N-pole module. It combines Type A residual-current detection at 30 mA with a B-curve 6 A overcurrent trip, rated for 6 kA breaking capacity. The 70 mm housing depth fits standard Siemens distribution boards and DIN-rail enclosures.
What the ratings mean for fit
Type A detection means this unit responds to sinusoidal AC residual currents and pulsating DC residual currents — the standard requirement for circuits with single-phase rectifiers, switched-mode power supplies, or electronic loads. The 30 mA sensitivity covers personnel protection (indirect contact) per IEC 60364. The B-curve 6 A overcurrent characteristic trips at 3–5× rated current, suited for resistive or lightly inductive loads like lighting circuits, small control transformers, or socket outlets. The 6 kA breaking capacity (Icn) is the short-circuit withstand for the device itself; verify that the prospective short-circuit current at the installation point does not exceed this value.