The Siemens 5SU1354-0KV16 is a combined residual-current device and miniature circuit breaker (RCBO), listed as a FI/LS-PROTECTOR TYPE AC (WS). It integrates ground-fault and overcurrent protection into a single 1+N-pole unit rated B 16A, with a rated residual operating current (IΔn) of 30 mA and a short-circuit breaking capacity of 10 kA. The Type AC designation means it detects sinusoidal AC residual currents only — suited for general socket-outlet circuits where DC fault currents are absent. The 70 mm depth fits standard distribution boards.
What the Key Ratings Mean for Fit
The B 16A overcurrent curve trips between 3× and 5× rated current (48 A to 80 A magnetic release), protecting 1.5 mm² to 2.5 mm² copper cable in residential or light commercial final circuits. The 30 mA residual-current element provides supplementary protection against electric shock — a standard threshold for socket-outlet circuits per IEC 60364. The 10 kA breaking capacity (Icn) at the rated voltage is sufficient for most TN and TT systems where the prospective short-circuit current at the point of installation stays under 10 kA. The 1+N-pole form factor switches the phase conductor and switches/isolates the neutral, occupying a single modular width.
Deployment Context
Snap-on mounting to a 35 mm DIN rail per EN 60715, with a 70 mm enclosure depth that clears standard distribution-board gland plates and busbar shrouds. The Type AC waveform sensitivity means this unit is not suitable for circuits with charging electric vehicles, variable-speed drives, or other loads that can generate pulsed or DC fault currents — those installations require a Type A or Type B RCD block.