Changed a cu today, On testing of the rings up and down.. end to end ground floor. R1 0.53 Rn 0.53 R2 0.79....first floor R1 0.54 Rn 0.53 R2 0.83..... Both rings were fine on the old rewireable DB. The ground floor ring is fine on the RCD, but the first floor trips, after testing it appears to be a fault between neutral and earth, I tried with just the live and neutral wired. no trip.....plugged in a tester and all three lights come on, I was expecting two lights suggesting no earth. the house has had four extensions over the years and it's a right balls up with sockets on the ground floor in the SNUG on the first floor ring. In one of the bedrooms upstairs in an extension there are two double sockets and one of these is a spur from the ground floor ring.......
Over the weekend I'm going to have to try and find this fault, and try and find where the earth is coming from.....Does anyone have any suggestions. ?????