Well all was dry today and it just kept tripping the consumer box.
Had to get the ever faithful plasplugs out for 900x600 porcs!
Finished work and dropped it off at the nearest dewalt service center.
They'll have a look at it on the bench first thing monday but looks like a damaged cable somewhere.
They said they've only ever had one come into them before and that was the inline circuit breaker that was faulty.
Spent nearly an hour just looking at all the kit they've got, wanted to buy everything! Did buy a couple of bi-metal saws for my fein - only £6 each (not fein originals)