Earthing water. Part plastic, part copper

[robsparx]

On the job I'm at, there is a plastic incoming water main, with a plastic pipe taken from it on the consumer side. The plastic runs up into a bathroom and copper pipe is taken off it to supply the bathroom. The plastic pipe carries on up into the loft which i then assume feeds more copper pipework.

As I see it, there is no requirement for supplementary bonding, as the copper is supplied by plastic. But there would be a requirement to earth any copper installation if it is introducing earth potential.

Would that mean I would have to seperately earth every piece of copper installation that is teed off the plastic. Not had too much experiences with plastic pipes before.

 

[malcolmsanford]

The copper pipe is not an Extraneous Conductive Part & only requires earthing if cables are run within 25mm. To cover yourself, do a test. I presume that all the power circuits are protected by a 30mA RCD?

Personally, I would bond all the copper pipe in the bathroom anyway. Better to be safe than sorry.

Could you be referring to Reg 528.3.4 and the note attached to this referring to BS 6891. ?

The onsite guide section 2.3 does give guidance on this and that is where this magical 25mm distance is cited. This is a distance recommended between electrical supplies and distribution cables and gas pipes.

This though is a recommended distance for gas fitters in their BS 6891, and not really aimed at us.

I also think you mean bonding rather than earthing

 

[Astro800]

Yes bonding, not earthing. The magical 25mm is mentioned in the newest 17th Edition though. I see what you mean about gas fitters BS 6891

 

[malcolmsanford]

Well mate be good if you find it to post that one up, as section 528 deals with proximity and 54 covers bonding and earthing and neither of these have this 25mm distance in it.

 

[Astro800]

I've started something now haven't I )

Have you ever mentioned something & wish you hadn't?:bigcry: I'm starting to feel like that. It's actually an exam question, one of those they give you to put you on the back foot.

I haven't the got the regs to hand at the moment, when I get them back I will see if I can find it again & post it up. Failing that I will text someone I am an acquaintance of at the Institute of Educational Technology. He is part of the team who writes the Regulations & sets the questions for the exams. (Why has my font changed? Sorry about the messy way it looks. Tried to put it right & made it worse)

 

[pushrod]

.

I haven't the got the regs to hand at the moment, when I get them back I will see if I can find it again & post it up. Failing that I will text someone I am an acquaintance of at the Institute of Educational Technology. He is part of the team who writes the Regulations & sets the questions for the exams.

I don't think he will be of much use - that IET is connected to the Open University nothing to do with "the wiring regs" - you want someone at the Institution of Engineering and Technology

 

[Astro800]

Yea, okay, tip of the slung, it's my age. Still not got around to contacting him, forgot, (it's my age )

 

[Top Cat]

Going slightly off subject i have found a lot of installations that have a plastic mains water supply, a plastic tap and about 1" of copper pipe then back in to plastic.

I have always run a 10.0mm e/wire to this tiny bit of copper but it seems such a waste of time. Is it really necessary?

 

[sedgy34]

guys!! :59:

if the main incoming water pipe is plastic you dont have to 10mm bond it!!! it dont matter if there are bits of copper joints in the house
the copper joints are because the plumber who was last in dont like using plastic (common sense) :crazy:

 

[Top Cat]

Thanks sedgy but is there a point when 1 mtr, 2 mtr, 3 mtr of copper pipe coming off plastic mains pipe, or feeding a metal sink in kitchen (that i know does not need bonding) starts to require a 10mm bond?

 

[Knobhead]

For your own peace of mind, bond the copper work. Saves the grief in the future when your held accountable for something going badly wrong.

 

[Top Cat]

Thanks Tony, that's what i have been doing. Just was not sure, as you say better to cover your but.

 

[Top Cat]

Thanks Tony, that's what i have been doing. Just was not sure, as you say better to cover your but.

Should have had two "t"s on but!

 

[sedgy34]

HEY TC
That would be a difference in interpretation i would 10mm bond if copper come off the plastic pipe in a kitchen!!! the thread said plastic going up to the bathroom then copper (would you run a 10mm bond to a 1mtr copper length under a bathroom floor) cause i wouldnt

 

[Geordie Spark]

I've started something now haven't I )

Have you ever mentioned something & wish you hadn't?:bigcry: I'm starting to feel like that. It's actually an exam question, one of those they give you to put you on the back foot.

I haven't the got the regs to hand at the moment, when I get them back I will see if I can find it again & post it up. Failing that I will text someone I am an acquaintance of at the Institute of Educational Technology. He is part of the team who writes the Regulations & sets the questions for the exams. (Why has my font changed? Sorry about the messy way it looks. Tried to put it right & made it worse)

Unless I'm much mistaken, that font is called "Comic Sans" and I think it's very appropriate for this forum.

 

[Top Cat]

HEY TC
That would be a difference in interpretation i would 10mm bond if copper come off the plastic pipe in a kitchen!!! the thread said plastic going up to the bathroom then copper (would you run a 10mm bond to a 1mtr copper length under a bathroom floor) cause i wouldnt

Sorry sedgy, did not really read the original thread (classic mistake!) actually i did not read it at all!!!

So going back to my original question, if you had a plastic water mains coming up in the kitchen with 1" of copper pipe would you run a 10mm bond to it?