Bonding Water and Gas

[wattja07]

Do I have to get the bonding for water and gas from the supplying MET or are you alloud to get it from a closer distribution board?

 

[paul b b]

sorry mate, could you give a bit more info

 

[M107]

What if the closer distribution board is removed or looses it's connection to the supply earth?

Having said that I'm assuming this is all in one building & not seperate buildings using the same supply.

 

[Manator]

I love part p

 

[doodneylucky13]

main bonding needs to be connected with in 600mm of the pipe work entering the building . It must be on the users side on the water ( after the stop cock) and before the first tee off on the gas.

 

[SLIPSHOD & SLAPDASH]

What if the closer distribution board is removed or looses it's connection to the supply earth?

Actually i clicked the wrong button there /\

I was going to quote and say thats the problem of whoever removes it. If the bonding is made to a sub board the earth feeding that must be of the correct size, normally 16mm for domestic but all jobs are different

 

[steptoe]

I love numpties 5WW competent folks that simply want re-assurance on their shortcuts. :x

 

[wattja07]

It's 3 phase, TN-C-S and the MET is 50M away. 2x. 4x185mm2 supplying the DB and a 50mm2 cpc

 

[steptoe]

:slap

have you considered the fact you may not be qualified for this sort of work?

 

[M107]

Use of building structural steelwork or metal pipework as the main protective equipotential bonding conductor?............. but you'll need to do some reading of the regs

 

[wattja07]

It's something that has been picked up on a PI and I was wondering if you guys could enlighten me on the regulations in wether your aloud to bond from a DB. . . .

 

[SLIPSHOD & SLAPDASH]

Try Googling 'Building earth marshalling terminal'

 

[steptoe]

This isn't a job in Farnborough is it ? Are you Polish ?

I dont think anyone has been polishing it, they want to know if its ok first, I think the idea is, if that its good enough they might try shine it up a bit to show it off though.

 

[Electroglow]

185mm I take it this is not a small place then

 

[brummydave]

It's something that has been picked up on a PI and I was wondering if you guys could enlighten me on the regulations in wether your aloud to bond from a DB. . . .

I can't find anything specific to say you can or can't bond from a DB. However, there's a lot of factors to take into consideration in this case and it'll all end up coming to your electrical judgement and calculation. As long as you can show reasoning, and label and document what you've done then you should be fine.

I found these tho:

Reg 542.4.1 says 'in every installation a main earthing terminal shall be provided to connect the following to the earthing conductor:

..

(ii) The protective bonding conductors (PBC)

..

In many installs the MET is inside a DB. However as your install already has one then I would favour taking the PBCs to it as 50m isn't that far. If you want two METs tho then you need to judge how to link them. Either with structural metalwork or cable.

Reg 544 is all about those pesky PBCs , and there's too much info to copy all here.

Basically, based on the size of your cpc you need protective bonding conductors of 25mm in copper (half) (544.1.1) unless...

If you've PME (which you probably have?), as your neutral is 185mm the main protective bonding conductor needs to be 50mm in copper (table 54.8) ...

or the DNO may want larger!

Yes there's also 544.1.2 about the 600mm incoming connection bit, but you already knew that eh

Hope this is helpful.