earth bonding

[bounce111158]

I need help.
I need to uprate my earth bonding from my fuse board to the meter using16mm cable.
I have a roll of earth cable left by an electrician about 3 years ago which has 7 strands and if i put a vernier gauge across the sheathing it is 7mm and across the copper it is 5mm.
Question 1. is this 16mm?
Question 2. Can i run 2 lots of 10mm earth cables in place of 1 single 16mm cable.
thanks in advance.

 

[ban-all-sheds]

Answer 1 - what is π x 2.5²?

Answer 2 - not really - why would you want to?

 

[ajrobb]

I was told by BC inspector that even qualified electricians must not tamper with stuff before the meter.

If you have upgraded your bonding to 16mm² then you could 'invite' your electricity supplier to connect it directly. I was advised to connect my bonding conductor to a stub of the old conductor.

 

[Spark123]

Can you post a photo? Do you have a main earth terminal which connects between the DNO fuse and the consumer unit?

 

[Risteard]

You appear to be describing the earthing conductor (not bonding). As others have said, you may not tamper with the cutout.

 

[ajrobb]

Can you post a photo? Do you have a main earth terminal which connects between the DNO fuse and the consumer unit?

The inspector (BC appointed electrician) said there isn't a 'proper' way of doing it. He accepted terminal block.

Modifying the CU comes under Part P and is notifiable to building control.

 

[Spark123]

All electrical work in domestic dwellings in England or Wales comes under Part P
Upgrading the earthing conductor or circuit protective conductor is, as you say, notifiable.

 

[Risteard]

Replacing the earthing conductor would require the supply authority to call out.

 

[ban-all-sheds]

I don't need a sparky to lift floor boards, cut holes,chop out for boxes or run cables.
These things i can do myself.
What i do need a sparky for,is to tell me what cable and what type of fuse to buy.
Speaking for myself, i would never do anything to put my life or that of my family at risk.

I will be doing no electric myself,only assisting the electrician when he comes.....I'll stick to the woodwork and decorating.

 

[ban-all-sheds]

You appear to be describing the earthing conductor (not bonding). As others have said, you may not tamper with the cutout.

So do you never get a TN-C-S cutout with the earth terminal exposed?

 

[ban-all-sheds]

Anyway - notifiable/not notifiable:

It can't be both not on your side of the meter, and therefore untouchable, and notifiable, since Part P does not apply to the parts of the installation on the suppliers side of the meter.

 

[ajrobb]

Anyway - notifiable/not notifiable:

It can't be both not on your side of the meter, and therefore untouchable, and notifiable, since Part P does not apply to the parts of the installation on the suppliers side of the meter.

The same LABC inspector told me that bonding connections are now made into the CU, which is the only thing connected to the supply's earth terminal. Work on bonding therefore requires work on the CU.

Is work on the CU earth bar notifiable or not?

 

[MalcofArabia]

Did you ask your inspector why, apart from the obvious fact that even if you turn of your CU's double Pole switch you will still have power on the supply side, that you can't change your bonding?

Table 1 of Part P advises you can install or upgrade bonding both main and supplementary without notifying, it does have a note about having to comply with other applicable legislation and it gives gas as an example.

In the notes concerning tables 1 and 2 they have a lovely little get out about risk of injury and fire and what is practicable, so in other words they are leaving it to the individual to make those assessments.

As you will not be adding new circuits to your CU then there is no reason not to do your own bonding.

So answer to your question about Earth bars, yes if your adding a new circuit it's notifiable, if your doing bonding then no it is not notifiable, but you will have to asses the risks of working inside your CU

Your bonding conductors are made into a MET which can be your Earth Bar in the CU or it can be a separate bar external to the CU. The Regs on page 32 in fig 2.1 gives you a lovely drawing showing your Bonding going to a MET not a CU Earth Bar

 

[Risteard]

NIE require that the MET is external to the distribution board. Not sure whether other DNOs have a similar policy.

 

[ajrobb]

As you will not be adding new circuits to your CU then there is no reason not to do your own bonding.

I'm glad about that.

During the inspection, he suggested I use the original 6mm² conductor to bond the copper pipes between the combi-boiler and the Speedfit/PEX/barrier pipes for the rest of the plumbing. He said it was "better than nothing". He accepted that it wasn't trivial to pull a 10mm² conductor through where the 6mm² conductor was running. The boiler had been installed by Gas Safe fitters so possibly outside his remit. Anyway, I had to reconnect the conductor to the earth bar in the CU so I could bond the boiler pipes.