Had this job today which i need to finish tomorrow - consumer unit change in a bungalow, TT system, all on a 30mA rcd.
There is no earth wire going from the earth stake to the fuse box. It is connected to a henley block within the meter cupboard just above and there is a twisted wire (uninsulated) about 4 strands going from the incoming mains cable into the same henly block. There is also a connection from mains cable into the neutral henly block but it is all wrapped up and cant see whether its another part of the twisted wires.
I thought "this cant be right, there must be an earth cable going to the fusebox surely". so with great difficulty I ran an earth wire to the new con unit, connected into the same henly block. There are 2 earth wires which appear to go from water and gas meter (bizarrly gas meter is next to fuse box and is underneath/next to kitchen sink unit, so I am extending all the house wires to a new position on the end of the kitchen unit run, so is more accessible.}
Anyway, the first test I did before power up was to measure Ze - with the new earth wire disconnected from bus bar, the meter wouldnt let me test it (came up with question mark). So i put the test lead on the earth bus bar (same as original setup) with new wire still disconnected - measured 6.3 ohm, so not bad.
Measured voltage between new earth wire and busbar - measured 16 volts; measured new wire to neutral and measured 1 volt.
From this I assume the the earth stake and neutral has been commoned up. Is this right - I never seen this before and my house is TT but not done like that..?
There is no earth wire going from the earth stake to the fuse box. It is connected to a henley block within the meter cupboard just above and there is a twisted wire (uninsulated) about 4 strands going from the incoming mains cable into the same henly block. There is also a connection from mains cable into the neutral henly block but it is all wrapped up and cant see whether its another part of the twisted wires.
I thought "this cant be right, there must be an earth cable going to the fusebox surely". so with great difficulty I ran an earth wire to the new con unit, connected into the same henly block. There are 2 earth wires which appear to go from water and gas meter (bizarrly gas meter is next to fuse box and is underneath/next to kitchen sink unit, so I am extending all the house wires to a new position on the end of the kitchen unit run, so is more accessible.}
Anyway, the first test I did before power up was to measure Ze - with the new earth wire disconnected from bus bar, the meter wouldnt let me test it (came up with question mark). So i put the test lead on the earth bus bar (same as original setup) with new wire still disconnected - measured 6.3 ohm, so not bad.
Measured voltage between new earth wire and busbar - measured 16 volts; measured new wire to neutral and measured 1 volt.
From this I assume the the earth stake and neutral has been commoned up. Is this right - I never seen this before and my house is TT but not done like that..?
