10 mm water bond ?

[BillyH]

I need to upgrade the bonding on a current installation but am having a problem locating exactly where to bond to. The consumer is in the cellar and so is the stop tap, however at some time in the past the pipe from the stop tap has been replaced with plastic, run across the wall and then disappears under a concrete floor. No one at the property knows where the platic ends and copper begins.All pipework throughout is copper except for the 3 mtrs from the incoming main.

Where would it be permissable to bond the 10 mm

 

[sambotc]

Am I correct in saying that if the incoming supply is copper then it would come under main equipotential bonding to a service, whereas if the supply is in plastic which then changes to copper inside the property, therefore unable to introduce a fault into the property, it comes under supplementery bonding which could then be classified as or not extraneous so could not actually be required?

 

[Deleted member 9648]

Not sure, but if it was i cannot connect here because of the 3mts of plastic in between .Surely its the pipework within the property that needs earthing

....You are getting your earthing and bonding mixed up,the pipework within the property does not need earthing....it is because it may be introducing the general mass of earth into the property that it needs bonding at the point of entry. Once within the property it doesnt matter whether it's earthed,bonded,plastic or copper....unless in a special location where supplementary bonding is required,which is a different thing altogether,but still nothing to do with 'earthing pipes'.

 

[Welchyboy]

....You are getting your earthing and bonding mixed up,the pipework within the property does not need earthing....it is because it may be introducing the general mass of earth into the property that it needs bonding at the point of entry. Once within the property it doesnt matter whether it's earthed,bonded,plastic or copper....unless in a special location where supplementary bonding is required,which is a different thing altogether,but still nothing to do with 'earthing pipes'.

^^^^^^^exactly my point, what you need to be concerned about is bonding any metalwork/pipework that has the potential of bringing in a different earth potential into the house, ie the suppliers side of the water main if it is copper/lead, i know we are taught to bond onto the side of the consumer but with this instance i would personally bond to the side of the supplier!

Note the cert, job Done!

by bonding the copper in the house after the pvc pipework you are totally missing the point of main protective bonding and its purpose

if you really like, belt and braces then bond to both sides!

 

[malcolmsanford]

Yes fella, i got what you were saying and i know the reg but i'm with spartykus and just like to do it (if i can)

I have to admit I'm a little concerned with that. By bonding a piece of metal that is not an extraneous conductive part, you would have a greater chance of making the installation less safe than safe.

As there is a good chance in the case of a fault you could introduce a fault condition on that piece of metal, in other words making it a protective conductor.

 

[grimysparks80]

I have to admit I'm a little concerned with that. By bonding a piece of metal that is not an extraneous conductive part, you would have a greater chance of making the installation less safe than safe.

As there is a good chance in the case of a fault you could introduce a fault condition on that piece of metal, in other words making it a protective conductor.

Ive been arguing this point with warm front inspectors for years. They dont care if its plastic incoming. they still want ME bonding on the first avilable bit of copper.

 

[malcolmsanford]

Ive been arguing this point with warm front inspectors for years. They dont care if its plastic incoming. they still want ME bonding on the first avilable bit of copper.

Have you advised them about how you can prove if it is/or isn't an extraneous conductive part?

Often even sometimes though the water supply in the house is plastic in places or even a plastic main incomer, if there is copper pipe to gas and the water supply to the boiler is also copper yes some parts of the installation could via the gas pipe be extraneous conductive parts.

A quick and easy test is IR with a wander lead on the main MET to the metal in question and if you have >22 KΩ then it is not an extraneous conductive part and no need for supplementary bonding.

I know the gas regulations still advise cross bonding and so perhaps they are using this as a belt and braces scenario, until something goes wrong that is