The Siemens 5SU1153-7KV13 is a combined residual current device and miniature circuit breaker (RCBO) — an FI/LS protector in Siemens' terminology — in a single 1+N-pole module. It integrates Type A earth-leakage detection at 10 mA IΔn with a C-curve overcurrent trip set at 13 A, all within a 70 mm-wide housing.
The 10 mA IΔn is the deciding spec for this unit — it is a sensitive Type A RCD, not the more common 30 mA. That sensitivity is specified for circuits where a lower touch-voltage threshold is required, such as socket outlets in wet areas, medical locations, or circuits supplying equipment with DC fault-current content (Type A detects pulsating DC residual currents). The C-curve 13 A overcurrent characteristic means the magnetic trip operates at 5–10× In (65–130 A), suited to moderate inrush loads like small motors, lighting ballasts, or control transformers.
The 70 mm width (D=70MM) occupies a standard DIN-rail module position — roughly 4 modular spaces at 17.5 mm each. The 1+N-pole construction switches the phase and switches/isolates the neutral, which is the common arrangement for single-phase final circuits in TN-S and TT systems. The Type A designation (PSE/SSF on the label) covers sinusoidal AC and pulsating DC residual currents up to 10 mA; it does not cover smooth DC faults, so verify the downstream load profile if variable-speed drives or UPS-fed circuits are present.