This is the standard everywhere in Europe, with separated earth and neutral wires which are connected and grounded somewhere farther. It is done for a purpose a

This is the standard everywhere in Europe, with separated earth and neutral wires which are connected and grounded somewhere farther. It is done for a purpose and not a problem when done properly. The resistance nor inductance is never enough to allow so high potential, even at kHz frequencies of switching power supplies. So this indicates a problem on earth wire that should be fixed by a professional, not by blindly adding some makeshift earthing.