On 27/05/2015 17:54, ARW wrote:
"dennis@home" wrote in message
web.com...

ITYM there are supposed to be two, but there is noway the home owner
will know and its too expensive to have them tested properly every
year or five.

http://martindale-electric.co.uk/mar...tor-p-285.html


Under £50



How does that know the ring is broken?
It would test a radial but would only partly test a ring and can't
identify a missing connection between power points.