Earthing

[needasparks]

Am i correct in saying that when an install is carried out Main and supplimentary bonding should be in place ?
went to a bathroom install and they had one of them rent a roof jobs done. Old wylex, usuall dated cabling. Had no main earthing on TNS (Earth on sheath was missing) prob fell off as old, no supplimentary to gas and water. This roof install was done a couple of months ago. So whats the score with the cert at the signing off as i've not seen one yet to know what things are checked in the install.

 

[malcolmsanford]

Well 132.16 does tell us that

​Furthermore the earthing and bonding arrangements, if neccessary for the protective device measure applied for the safety of the addition or alteration shall be adequate

I would guess that none of either is not adequate

 

[Octopus]

Well 132.16 does tell us that

​Furthermore the earthing and bonding arrangements, if neccessary for the protective device measure applied for the safety of the addition or alteration shall be adequate

I would guess that none of either is not adequate

Do they have that printed in the Big Sheds then????????

 

[moggy1968]

It is a requirement that before any electrical work is carried out on an installation the main equipotential bonding and earthing must be to the required standard. This applies wether your putting in an extra socket or a PV system
This is not supplementary bonding. It is main protective bonding. You seem to be confusing the two. Supplementary bonding is the cross bonding within the installation between pipwork and some other metal parts. Providing certain conditions are met this is no longer required. If it was required someone installing new circuits would not be required to install it unless it was relevant to the circuits they were working on. I would mention it on the installation certificate though. If you were doing bathroom circuits you would have fitted an RCD. This means that probably you have met the requirement to not need supplementary bonding provising all the circuits in the bathroom were RCD protected. I say probably because there are other requirements before supplementary bonding can be ommited.
You can get away with the existing being less than 10mm providing the resistance is below 0.05Ohms I believe.
An installation certificate and schedule of test results should have been issued on completion and these have a section for the installer to confirm main bonding and earthing are in place and satisfactory

 

[GaryM]

Do they have that printed in the Big Sheds then????????

No but ignorance isn't an excuse.

 

[Octopus]

No but ignorance isn't an excuse.

Not ignorance on my part BUT we professionals are tied down by rules that the vendors don't promote, nor the schemes.

 

[GaryM]

Had no main earthing on TNS (Earth on sheath was missing) prob fell off as old, no supplimentary to gas and water.

Just a minor detail - it's an earthing conductor, not a main earth and it's main protective bonding conductors that are terminated to the incoming water and gas supplies, not supplementary bonding conductors.

 

[GaryM]

Not ignorance on my part BUT we professionals are tied down by rules that the vendors don't promote, nor the schemes.

No, not at all on your part but on the part of the DIY'er who thinks that it's just a case of buying a bit of cable and a couple of socket. Bodge them together and if the bedside lamp works then it must be fine. Why should he pay £200 or so for a qualified electrician?

 

[needasparks]

This is not supplementary bonding. It is main protective bonding.

Yes, my appologies. Mind went off then. I meant Main Protective bonding. Was reading the othe thread and it just popped in there, whoops.
Just seemed to me the whole install was rushed and lashed up. I'm no expert on PV installs but even I could see it was rubbish.
Big holes left in the roof allover where the grid was bolted to the trusses and daylight was so bright from it i did not need a torch in the loft to sort the lighting cables to the job i was on. So do these installs get checked by registered body or what ?

 

[GaryM]

It would have been interesting to see the Electrical Installation Certificate for the AC side of the PV install.
Bet it wouldn't resemble that installation!

 

[the oracle]

Your post states that the installation " Had no main earthing on TNS (Earth on sheath was missing) prob fell off as old," ? If this is true then the installation is highly dangerous and needs immediate action as there is 'Danger present'! I assume you took care of that?

The 'rent a roof mob' would have been unable to complete an EIC for their work, as the presence and suitability of earthing and protective bonding conductors is an important part of certification. Supplementary bonding would also be required normally if there are no RCD's present. I somehow get the feeling that they probably didn't/couldn't/wouldn't certify their work probably because they don't have a clue about inspection, testing and certification! They would not have been able to carry out Zs tests either, so it does not bode well!

Have a look at the model forms in the Regs, Appendix 6. If you have not got a copy (and why not !!) check out the IET website, under 17th Edition, they have them all on there!

The Oracle

 

[moggy1968]

Yes, my appologies. Mind went off then. I meant Main Protective bonding. Was reading the othe thread and it just popped in there, whoops.
Just seemed to me the whole install was rushed and lashed up. I'm no expert on PV installs but even I could see it was rubbish.
Big holes left in the roof allover where the grid was bolted to the trusses and daylight was so bright from it i did not need a torch in the loft to sort the lighting cables to the job i was on. So do these installs get checked by registered body or what ?

unfortunately no they aren't, but that doesn't sound good TBH. the installation shouldn't compromise the integrity of the roof at all. I think they need to canvas a second opinion from a qualified installer.
A breach is best reported to trading standards. None of the professional bodies are much good. REAL and MCS are only interested in wether your paperworks correct, not wether the jobs actually any good! The electrical bodies aren't much better.
If the main earth is missing the installation must be switched off and the DNO notified, they'll be down there pretty sharpish!

 

[SolarCity]

If the main earth is missing then I'm absolutely staggered. How on Earth could any sparky leave it in that kind of condition?

 

[telectrix]

If the main earth is missing then I'm absolutely staggered. How on Earth could any sparky leave it in that kind of condition?

answer is in the OP. "rent-a-roof". all they want is the income as fast as possible, for the minimum cost of installation.

 

[Glen Powell]

answer is in the OP. "rent-a-roof". all they want is the income as fast as possible, for the minimum cost of installation.

You seem to be tarnishing all with one brush, I supply to funds and our company has installed a few to help out.

A large number of the installers do look at the bonding and safety, I know this because they phone up asking why we did not supply any earth cable, etc. I have to explain that we supply the PV kit only. RCD, RCBO, bonding, rods, etc. should be quoted and supplied by the electrician.