Main earthing Conductor also bonds water

[Timotei]

Domestic TNCS, main earthing conductor runs to water pipe, bonds via clamp with label, cable is continuous, then runs on to MET in DB.

Seems wrong, but cant find specific reg to say so....any thoughts?

Thanks,

Timotei

 

[Strima]

Its an earthing conductor not a main protective bonding conductor. Part 2 definitions. Fig 2.1.

But I can't see anything specifically prohibiting it.

 

[Wilko]

Makes it difficult to measure Ze accurately / properly ... but I'm stuck for a reg just now.

 

[The Ghost]

I think @Wilko has it with the Ze problem. And looking at 542.4.1 (18th) it states an MET shall be provided...
and at 542.4.2 ...To facilitate measurement of the resistance of earthing arrangements...
So checking bonding requirements and Ze would be a bit of a conundrum and it could be argued unless there is separate MET complying with the former reg. then it would not comply?

 

[Deleted member 26818]

How is the earthing conductor connected at the supply end?

 

[johnduffell]

Agree with V above, you need an MET somewhere. It's still safe so perhaps it wouldn't attract a classification on an eicr but it's going to be a pain to deal with.

 

[Intoelectrics]

I think @Wilko has it with the Ze problem. And looking at 542.4.1 (18th) it states an MET shall be provided...
and at 542.4.2 ...To facilitate measurement of the resistance of earthing arrangements...
So checking bonding requirements and Ze would be a bit of a conundrum and it could be argued unless there is separate MET complying with the former reg. then it would not comply?

I have agreed with you, though if the clamp to the water pipe is easily accessible and the conductor is continuous then measuring the Ze may not be a major problem. Not ideal though, I agree. I would definitely look at running in a separate conductor, just in case wet pants comes along and does some pipework alteration and decides to just cut through the cable.