1) in my 1960s house, most of the ring main has multistrand earth conductor; it looks as if it has the same x-sectional area as the L and N. However, one part (added later) uses cable with only a single strand earth. the L and N seem to be the same area (2.5 sqmm).
If a house uses a mixtrure of earth sizes does this not mess up a ring conductivity test? The expected earth resistance cannot be calculated properly so how can it be checked?
2) The cooker to wall outlet uses a 6 sqmm cable. the L and N are multistrand but the earth is a single strand. The cable came from Homebase and was sold for the purpose. Surely in an appliance cable should have multistrand earth to avoid fractures due to repeated flexing. the cooker is regularly pulled out for cleaning etc.
Nobody seems to sell 6sqmm cable designed for flexing (currys comet homebase bnQ). is it really normal to use "single strand earth" cable for a cooker?
thanks for any comments anyone cares to make.