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Lighting circuit earths left disconnected

Postby mito » Sun Aug 08, 2010 6:36 pm

Hi, as part of a kitchen re-fit I had to have the consumer unit replaced and new earths provided. The work was carried out by the kitchen fitter's electrician. To say I was less than impressed with the electrician would be an understatement, but that's a different story!

He told me it was not unusual after a consumer unit is changed for earth leakage problems to be highlighted by the sensitivity of modern RCD units. However, after the changeout I was lucky it seems, as there were no apparent problems.

Today I decided to replace the dining room light fitting. When I unscrewed the rose, I noticed that one of the earth wires was disconnected. I reconnected it when I fitted the replacement rose, but when the RCD was switch on again, the RCD group switch (MCD?) tripped out. Disconnecting the earth again allowed it all to work again.

Using a meter, I discovered that there was no earth on the earth wire coming from the direction of the supply. Checking the next ceiling rose along, the cloakroom, I found the earth in there had also been disconnected. Note these weren't wires broken off, but terminals unscrewed and earth wires removed.

I know I wouldn't have left them like that, so it looks like when the consumer unit was changed, the electrician had problems with the downstairs RCD lighting circuit tripping. Rather than sort the problem out he disconnected the earths to get round it - and left it that way.

I'm guessing the earths are pretty important! However, it's just possible I suppose that maybe when modern RCD are fitted they're not. Before I go back to the electrician, who I don't trust one little bit, I want to be sure I've got my facts right.

What would be the view of the forum on earths left disconnected on lighting circuits to prevent RCD's tripping?

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Postby ericmark » Mon Aug 09, 2010 11:27 am

If the electrician had disconnected earths to stop the RCD tripping I would consider he had not shown a “Warrantee of Skill” and I would hope the firm he worked for would immediately dismiss him which is their right when caught doing a dangerous practice.

However back before 1966 it was not required to have earths on lights and many houses don’t have earths on lighting. However one would have expected the electrician to have done a periodic inspection report as part of the job of changing the consumer unit. You should have received two sets of paperwork. At the time of the job he should have issued a installation certificate and this will include a schedule of test results he should have entered on this the earth loop impedance in ohms and the time it took the RCD to trip in milliseconds (ms) it would be interesting to see his figures if left disconnected.

Secondly likely through post you should have received a completion certificate to show his scheme operator or the LABC had looked at their copy of the schedule of test results and accepted the readings as being within the accepted limits and have logged the work with the LABC.

It should have the details of the scheme operator and if you think he did disconnect the earths then you should contact them. They will then likely send an inspector and if they believe he has removed the earths he will loose his Part P self certification rights and will no longer be able to do domestic work requiring certification without paying the LABC for each job.

If you did not get a completion certificate then I would ring the local council and complain.
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Postby mito » Mon Aug 09, 2010 8:32 pm

Thanks for the reply and info.

I did get the certificates you mention, both NICEIC ones.

The one issued for the installation on the day was completed and signed by the company owner, even though he was away on holiday on the day the unit was changed; the work was carried out by his sole employee.

Without going into detail, the owner of this company has without doubt ripped me off over other work completed and goods supplied. I don't trust him and would rather not have anything further to do with him.

I'm fairly sure the earth problem is on the cable run between the dining room and the cloakroom. It should be fairly easy for me to prove and if necessary I may get another electrician to take a look and test it.

Thanks again.
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Postby sparx » Tue Aug 10, 2010 9:02 am

hi, sorry to hear of your problems,
unfortunately the NICEIC run a scheme using 'Qualified Supervisors' which means a firm only needs to have one person with 17th edition regs qualification and they can sign off certs for work done by any of their employees who don't have to anything!

No other part P organisation allows this.
Elecsa, BRE, NAPIT all insist all 'operatives' are fully qualified in their own right, as they should be IMHO.

As Ericmark says, lighting circuits were not always earthed so giving benefit of doubt the person doing the board change should at least put a label on consumer unit as proscribed in the onsite guide stating
"circuit# X has no CPC, only class II fitings not requiring earth should be fitted" & should have brought it to your attention!

His only saving grace was to point out to you before starting of the possible tripping out following fitment of RCD's which may pick up long standing N-E faults not always apparent.

Please don't let this company off the hook too easily, if another leckie is prepared to prove CPC disconnected intentionally they should be reported.

regards Sparx
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Postby mito » Mon Aug 16, 2010 5:58 pm

Thanks for the additional info Sparx.

Very interesting about the NICEIC 'Qualified Supervisors' scheme. Something to be aware of next time I need to get an electrician in!

I haven't had a chance to do any further diagnostics yet. Hope to tomorrow. If a few basic tests don't reveal the problem, I'll certainly get a (non-NICEIC) qualified electrician to give it the once over.

If they think the previous work has been sub standard be assured I'll take it further.
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