Cable Ratings dot co dot uk i think
Some NIC site i've just been looking at states 'For a single cable likely to be totally surrounded by thermally insulating material for a length of 0.5 m or more, the current-carrying capacity must be taken as 0.5 times the current-carrying capacity for that cable clipped direct to a surface (Reference Method C).'
So ring finals should be only able to carry the 'normal' clipped current of a single 2.5mm cable at ~27a.
I just want to know why 16a + 1.5mm is apparently borderline dangerous but 32a + 2.5mm isn't? Eager to learn.