What it is – RCBO in a single module
The Siemens 5SU1656-7KV06 is a combined residual-current circuit breaker (RCD) and miniature circuit breaker (MCB) – an RCBO – in a 1+N-pole format. It packs a Type A residual current device rated 300 mA and a C-curve MCB rated 6 A with a 6 kA breaking capacity into a single 70 mm wide module.
What the ratings mean for fit
The C-curve (6 A) trips between 5 and 10 times rated current – 30 to 60 A – making it suitable for motor and inductive loads that draw a brief inrush. The 300 mA residual sensitivity (Type A) catches pulsating DC fault currents common on single-phase electronics and variable-speed drives. The 6 kA breaking capacity at the rated voltage covers most domestic and light commercial panel faults, but check the prospective short-circuit current at the installation point.
Where it goes – panel integration
Snaps onto DIN rail in a consumer unit or distribution board. The 1+N-pole format switches the line and switches the neutral pole as well, so it fits sub-distribution circuits requiring both overcurrent and earth-fault protection in a single device. The 70 mm width takes two standard 17.5 mm module spaces plus a bit – plan the enclosure layout accordingly.