Should the underground cable to the garden be secured again?

The primary concern is whether personal safety for the garden installation is ensured by the circuit breakers and RCD in the distribution board.

That must already be guaranteed!

That the living room isn't dark in case of a fault would be more of a nice to have.

Then you don't need to change anything.

A circuit breaker in the garden would at least make it possible to disconnect the garden from power for fault finding, without simultaneously disconnecting the living room.

That doesn't really help. A circuit breaker only switches the phase, but the RCD trips also with currents between N and PE.

Ok, what kind of switching device is there that I can install in the garden and that allows me to safely search for faults in the garden while the power remains available in the living room and the rest of the house?

That’s why a 10mA RCD is installed, then the upstream 30mA RCD usually does not trip. But if it’s just nice to have, then better leave it. Selectivity was not covered in the training, you have to forgive Rotormotor.

Well, it would be nice to be able to completely separate the garden. If something buried in the ground causes a short circuit and I might only get around to fixing it in hours or days, and the TV & Co. don’t work in the meantime, various family members here will eventually go up the walls ;). Maybe something like that also happens during frost or or...

That's why you install a 10mA RCD, then the upstream 30mA RCD usually doesn't trip. But if it's just nice to have, better leave it. Selectivity wasn't covered in training, you have to forgive Rotormotor.

Aiaiai, sounding pretentious when you have no clue is really great. So putting a 10mA behind a 30mA RCD and at the same time babbling about selectivity... What nonsense...

So could the 30mA RCD in the fuse box also fly along? That would be OK for me, because after all, I can first try to switch it back on. If it then stays on together with all the circuit breakers in the meter cabinet, then there is a problem in the garden installation and I can safely start looking there. Or am I mistaken?