Ah! The manufacturers most commonly seem to say about 1.7 Nm for MCBs and 2.0 or 2.3 Nm for RCDs/main switches etc. However, if I use those torques, I can get get them a lot tighter with an ordinary screwdriver (applying the judgement I would normally apply) without using excessive force and without any feeling that I am getting anywhere near shearing anything off.Ha ha - having said what I did, I guess I should fess up to neither owning a torque setting screwdriver nor having looked to see what torques are specified. But many years of using my judgement with ordinary screwdrivers has not resulted in overheating, let alone fires, nor any screws shearing off.
Kind Regards, John
