The Siemens 5SU1156-7KV16 is a combined residual-current device and miniature circuit breaker (FI/LS protector), Type A, rated IΔn 10 mA sensitivity and 6 kA breaking capacity, in a 1+N-pole configuration with a C 16 A trip characteristic.
Deployment context
The 1+N-pole form factor snaps onto DIN rail in a standard distribution board. The Type A (PSE/SSF) classification covers the German PSE/SSF specification for selective earth fault protection — typically installed in sub-distribution boards where the upstream RCD is also Type A and coordination requires a lower IΔn or a time-delay characteristic. The C 16 A curve handles motor inrush and transformer magnetizing currents without nuisance tripping; pair it with a 16 A rated load, not a 20 A circuit.