TT off water main or tncs with no earth (Victorian house city centre)

[James Kinrosd]

Hi guys came across this today, Ze of 37 ohms, surprised me as thought it was a tncs- Victorian house, Db from 1989, no docs- could it be a TT off the water main? 10mm bonding to gas and another 10mm out of sight. The met on the rhs of tncs
block not connected to neutral- can anyone help me with some ideas? Cheers.

 

[Strima]

Yes, last sentence of 542.2.6 -Other metallic water supply pipework shall not be used as an earth electrode unless precautions are taken against its removal and it has been considered for such a use.

So it can be used.

 

[DPG]

Yes, last sentence of 542.2.6 -Other metallic water supply pipework shall not be used as an earth electrode unless precautions are taken against its removal and it has been considered for such a use.

Hoist by your own petard it would seem.

 

[BOYD BARKLEY]

200 Ohms is the value recommended not to be exceeded in regs, as you well kn0w . Yes NICEIC do recommend under 100. For an earth electrode. So far as the nonsense is concerned(I'll be objective here not obstructive)If you look at B.S.7430 IT RECOMMENDS 100 ohms max and 2 meters of rod as the top meter of soil can be unreliable. Eh?

542.2.6 Says other metallic water supply work can't be used unless
precautions are taken and it's been considered for use. So if you'r
desperate and can understand what that means, and what ''Other''
is and you can be bothered with all the hassel , you can. Maybe.

 

[Octopus]

Yes, last sentence of 542.2.6 -Other metallic water supply pipework shall not be used as an earth electrode unless precautions are taken against its removal and it has been considered for such a use.

Keep digging ...........

the important part is highlighted above.

 

[BOYD BARKLEY]

Keep digging ...........

the important part is highlighted above.

Yes it's all there