I've been called back to a job where I have put in a ring main.. I've used metal clad face plate and back boxes. When wiring all I have simply done is used the incoming earth and terminated to the face plate and used the out going earth to terminate to the back box. Their saying that both earths should be in the face plate with a separate fly lead going off to the back box. Surely terminating 3 2.5mm earth into one terminal there is more chance of it coming loose? Is this a regulation??