Major works notification

[Chector]

Hi, I've changed a consumer unit for a customer but noticed the earth and bonding conductors were undersized at 6mm csa. Do I put this down as a departure from 7671 or not issue to cert until the problem is rectified?

Thanks

Chris

 

[Pete999]

Perhaps it would have been best to have tested and replaced if necessary before you changed the CU. that would have been my choice, others may differ though.

 

[SteveH40]

dont do much domestic but would imagine you can still certify the work you have completed and code the bonding accordingly but also stress the importance of the rectification works to the customer.

 

[uksparks]

Hello,

Please do not take this the wrong way, but having looked at your profile you say you are an electrician and not a trainee, so can only give you advise based on this level of standing.

When you carried out all your pre checks and tests on the old consumer unit / fuse box, you would have noticed that the main protective bonding conductors were less that the size they should ideally be.

What size is the main fuse, and what size are the meter tails please.

On the basis the tails are >16mm then I would want to see 10mm bonding conductors to the main services, be it water or gas etc.

Any electrical work that you undertake, the earthing must be up to standard, in my opinion putting it down as a departure on the certificate is not the correct way of doing it as they are there to help save your life, so on that basis, making a note on the cert is not right.

You should have updated the earthing and bonding arrangements prior to your changing the consumer unit or at the same time as, because now, you have energized an installation that is potentially unsafe, ok no worse than it was before, but thats not the point.

Some will say if theres no signs of thermal damage etc to the bonding conductors and the BS951 clamps are in good order with sound connections, but if it was me I would want a 16mm main earthing conductor, and 10mm main protective bonding conductors.

What color is the 6mm you have got, is it green and yellow or solid green?

Also, what size is the earthing conductor and what supply type is it? TNS? TNC-S? TT?

 

[uksparks]

With reference to a post you made just 5 days ago, I can only assume this is the same property:

"I would value peoples opinions the earthing arrangement I cam across yesterday. Water and Gas main protective bonding conductors were not installed at the consumer unit, but were coned to the main earthing terminal. The MET was connected to the distributors earth and one conductor ran from the MET to the consumer unit. The resistance from the consumer unit to the gas and water were fine at 0.01 Ohms. But shouldn't the conductors be wired into the consumer unit? They all need changing anyway as they were all 6mm."

http://www.electriciansforums.co.uk...trical-forum/102345-earthing-arrangement.html

So based on this, you knew they were on the small side before you started the work, so why have you carried on and not updated them?

 

[Welchyboy1]

Existing 6mm earthing and bonding does not mean you have to automatically upgrade them, even for a pme system, refer to the ESC guide for further clarification on this

 

[uksparks]

Existing 6mm earthing and bonding does not mean you have to automatically upgrade them, even for a pme system, refer to the ESC guide for further clarification on this

I appreciate they don't have to be updated, but its good practice and makes for a better job.

 

[telectrix]

as trhe previous post #6. 10mm main bonding is only required on a PME system, and even then can be left as is if certain conditions are met.

 

[uksparks]

as trhe previous post #6. 10mm main bonding is only required on a PME system, and even then can be left as is if certain conditions are met.

just to add....If its solid green it needs replacing though.

 

[telectrix]

just to add....If its solid green it needs replacing though.

not if you add some yellow tape, srtategically spaced.

 

[Sintra]

Hi, I've changed a consumer unit for a customer but noticed the earth and bonding conductors were undersized at 6mm csa. Do I put this down as a departure from 7671 or not issue to cert until the problem is rectified?

Thanks

Chris

"No addition or alteration, temporary or permanent, shall be made to an existing installation, unless it has been ascertained that the rating and the condition of any existing equipment, including that of the distributor, will be adequate for the altered circumstances. Furthermore, the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate."

If you have confirmed that the earthing and bonding arangements are adequate then issue your cert. If not then as you have carried out work then it is up to you to make them adequate.

 

[GB.Kayak]

"No addition or alteration, temporary or permanent, shall be made to an existing installation, unless it has been ascertained that the rating and the condition of any existing equipment, including that of the distributor, will be adequate for the altered circumstances. Furthermore, the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate."

If you have confirmed that the earthing and bonding arangements are adequate then issue your cert. If not then as you have carried out work then it is up to you to make them adequate.

Hey S, your quote reads as authoritative, please would you quote its source in order to confirm its authority beyond being 'sensible practice' and good advice from an experienced electrician and a moderator or administrator on this site?

 

[Andy78]

Hey S, your quote reads as authoritative, please would you quote its source in order to confirm its authority beyond being 'sensible practice' and good advice from an experienced electrician and a moderator or administrator on this site?

I take it you are asking this for the benefit of the OP ? Even though he really should know where this is from being a practising electrician. Not sure it matters anyway as he seems to have cleared off like his last thread.

BS7671, chapter 13 fundamental principles, regulation 132.16 to save Sintra a job.

 

[GB.Kayak]

I take it you are asking this for the benefit of the OP ? Even though he really should know where this is from being a practising electrician. Not sure it matters anyway as he seems to have cleared off like his last thread.

BS7671, chapter 13 fundamental principles, regulation 132.16 to save Sintra a job.

A, thanks ... I thought that it was most likely to have been drawn from a recent edition of the BB. I fear that I have been a little lazy, not searching it out for myself. That said ... I was always taught at University to quote my sources!

 

[ruston]

A, thanks ... I thought that it was most likely to have been drawn from a recent edition of the BB. I fear that I have been a little lazy, not searching it out for myself. That said ... I was always taught at University to quote my sources!

I thought you were just being polite with a hint of sarcasm.:smile5: