How can you Earth Bond plastic incoming mains water pipe?

[Pip]

Hi People,

Looked at a job today which requires adjustments to the CU and noticed there is 16mm from CU to MET which is cool, 10mm from MET to Gas main incoming, and bonding between all pipes coming in and out of the boiler linked off the GAS main bonding.

When I pointed out that there should be a 10mm to the mains water incoming the customer informed me that there was not one fitted as the incoming pipe is plastic, and most of the fittings in the house were a mixture of plastic and copper, so would be no use as an earth bond.

I could see his point, but where do we stand on such a situation?

Pip

 

[Pip]

By the way the system is a PME system underground mains incoming

 

[Sparky Ninja]

check out 544.1.2

 

[IQ Electrical]

Have a read of this:

 

[Sparky Ninja]

Have a read of this:

I'm getting a bit of deja vu, this keeps coming up.

 

[telectrix]

Have a read of this:

just had a quick look at that pdf. it's 16th, out of date.

 

[IQ Electrical]

just had a quick look at that pdf. it's 16th, out of date.

So's Guidance Note 8 but it's all we have at the moment....

Still some good stuff there though.

 

[Sparky Ninja]

just had a quick look at that pdf. it's 16th, out of date.

that was brought up last time we used it, but until something more resent is brought up..?...?...?

The reg I quoted is to date, and informs us that PVC supplied services with metallic framework downstream can be subject to bonding.

 

[Pip]

I thank you very much, it has been very enlightening, after I put up the post, I did look closer on the site and yes I can see why you are getting your De Ja vu, the question has been asked a few times recently, with some conflicting answers, which what you expect on such a subject

Again many thanks Pip

 

[lamb]

A plastic incoming service cannot, by definition, be an extraneous conductive part, ie. a part that is liable to introduce an earth potential or any other potential into an installation. Therefore main equipotential bonding is not required.

There is a standard test, described in GN8, to confirm whether an incoming service is or is not an extraneous conductive part. Using a high-reading ohm-meter, resistance is measured between the part and the MET of the installation. If above 56K Ohm it is not an extraneous conductive part.

 

[Sparky Ninja]

This has been covered.

 

[IQ Electrical]

Done to death!

 

[ezzzekiel]

but still not resolved in my opinion, sitemanager insists its not fitted, qs insists that a bond is made to wherever the incoming plastic turns to copper (wherever that may be), niceic are supposedly going to get back on this one, as stated earlier i would always bond at the first available place but it would be nice to get a definitive answer on this one.

 

[IQ Electrical]

but still not resolved in my opinion, sitemanager insists its not fitted, qs insists that a bond is made to wherever the incoming plastic turns to copper (wherever that may be), niceic are supposedly going to get back on this one, as stated earlier i would always bond at the first available place but it would be nice to get a definitive answer on this one.

When you say wherever the plastic changes to copper, are you talking about say 1 metre of copper, 8 metres of plastic, another metre of copper etc?

 

[ezzzekiel]

no mate copper incoming direct to stop tab then plastic in bathroom, goes underground and reappears near to combi which is the next closest place to put the bond.

one next door has copper intake then about 2 metres plastic returning to copper in same room, so a clamp can go on to the coper near the stop tap.

interested in your views on this as i still think a bond should be put in wherever the first point is that you can fit one. Everyone seems to have a diffent opinion.