Hi Chaps,
According to the neighbours the road used to get half a dozen powercuts a year, often lasting for hours at a time. So there would have been some sense in having a generator hookup. This would almost certainly have been done in the early eighties. The guy who owned it then was not short of a bob or two and while he seems to have gone to extremes in some places none of it looks DIY. About 8 years ago something got upgraded and since then powercuts have been rare so its no longer an issue.
I had a prod around the socket with a multimeter and there is no voltage across the live and neutral.
Everything is pointing to a generator hookup but with a socket where there should be a plug. That makes no sense but maybe the rules were different in the eighties.
I've also found a number for B&D so I'll give them a ring and see if they can id the switch box.
Prodave, I haven't tried the switch to see what happens yet. Now I know where the SWA goes I'll find a time after I've talked to B&D and give it a go. Assuming all the house power goes off when I flick the switch Is there anything I could safely test? Continuity between the commando socket live and a standard 13A socket live for instance?
Thanks for all the comments & help guys, have a good weekend whatever you are up to.
Oddbod