On 11/02/2017 08:44, Brian Gaff wrote:

I would also hope any relay system would be so designed not to arc.
Something an old portable radio with medium way will tell you I'd imagine
Brian


Now it's no longer on an RCD I may well try that - not that it will tell
me which one of the umpteen* on the control board that it is.

*Ok there are only 10, but I don't fancy replacing all of them just
because