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Topic Title: Inspection & Testing
Topic Summary: Certification of electrical work
Created On: 18 September 2013 09:38 AM
Status: Read Only
Linear : Threading : Single : Branch
 Inspection & Testing   - mazzy2000 - 18 September 2013 09:38 AM  
 Inspection & Testing   - AJJewsbury - 18 September 2013 09:56 AM  
 Inspection & Testing   - John Peckham - 18 September 2013 09:58 AM  
 Inspection & Testing   - OMS - 18 September 2013 10:10 AM  
 Inspection & Testing   - daveparry1 - 18 September 2013 11:30 AM  
 Inspection & Testing   - MrP - 18 September 2013 12:11 PM  
 Inspection & Testing   - alanblaby - 18 September 2013 03:31 PM  
 Inspection & Testing   - rocknroll - 18 September 2013 03:51 PM  
 Inspection & Testing   - Parsley - 18 September 2013 04:25 PM  
 Inspection & Testing   - leckie - 18 September 2013 04:26 PM  
 Inspection & Testing   - OMS - 18 September 2013 05:34 PM  
 Inspection & Testing   - Zs - 18 September 2013 09:58 PM  
 Inspection & Testing   - Legh - 18 September 2013 10:50 PM  
 Inspection & Testing   - AJJewsbury - 18 September 2013 04:19 PM  
 Inspection & Testing   - AJJewsbury - 18 September 2013 10:19 PM  
 Inspection & Testing   - John Peckham - 18 September 2013 10:29 PM  
 Inspection & Testing   - normcall - 19 September 2013 06:33 AM  
 Inspection & Testing   - davezawadi - 19 September 2013 07:07 AM  
 Inspection & Testing   - leckie - 19 September 2013 07:32 AM  
 Inspection & Testing   - dickllewellyn - 19 September 2013 07:53 AM  
 Inspection & Testing   - OMS - 19 September 2013 03:15 PM  
 Inspection & Testing   - leckie - 19 September 2013 05:22 PM  
 Inspection & Testing   - iie62478 - 19 September 2013 05:42 PM  
 Inspection & Testing   - OMS - 19 September 2013 06:11 PM  
 Inspection & Testing   - kj scott - 19 September 2013 06:33 PM  
 Inspection & Testing   - OMS - 19 September 2013 06:42 PM  
 Inspection & Testing   - kj scott - 19 September 2013 06:53 PM  
 Inspection & Testing   - OMS - 19 September 2013 07:40 PM  
 Inspection & Testing   - leckie - 19 September 2013 09:33 PM  
 Inspection & Testing   - OMS - 20 September 2013 10:15 AM  
 Inspection & Testing   - Parsley - 20 September 2013 10:54 AM  
 Inspection & Testing   - OMS - 20 September 2013 11:57 AM  
 Inspection & Testing   - Parsley - 20 September 2013 02:33 PM  
 Inspection & Testing   - leckie - 20 September 2013 03:31 PM  
 Inspection & Testing   - OMS - 20 September 2013 04:18 PM  
 Inspection & Testing   - sparkingchip - 20 September 2013 07:39 PM  
 Inspection & Testing   - kj scott - 20 September 2013 07:59 PM  
 Inspection & Testing   - Legh - 20 September 2013 01:36 PM  
 Inspection & Testing   - kj scott - 19 September 2013 08:08 AM  
 Inspection & Testing   - mazzy2000 - 19 September 2013 08:27 PM  
 Inspection & Testing   - dickllewellyn - 19 September 2013 09:31 PM  
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 18 September 2013 09:38 AM
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mazzy2000

Posts: 35
Joined: 25 June 2013

I know this topic has been discussed previously, but I am trying to gauge opinion a bit further.

My team of electricians recently carried out a distribution board replacement feeding circuits at a small railway station and in their opinion, it does not require an electrical installation certificate. My interpretation of the regulations is that this work should have been certified in accordance with 610.6 as it is an alteration in accordance with 610.4.

There are two types of certificate, but the notes on the minor works cert preclude it from being used for DB changes; therefore, an electrical installation certificate must be issued together with a full schedule of inspections and tests. This would include relevant tests/inspections on all the final circuits, even though they have only been disturbed at the distribution board.

Their argument is that there is already a valid periodic report for the board and that the board is being changed from a 30 year old Ottermill quicklag style to a modern Schneider board with type B/C circuit breakers; therefore, it is safer.

Another agrument for issuing the certificate would be for recording the differences between the two installations, even though they have likely been improved e.g. main switch characteristics, different circuit breaker characteristics (5A to 6A, 30A to 32A etc.). Also, this cert is signed off to indicate that the new installation has been designed, constructed and inspected/tested in accordance with 7671.

As a compromise, they have agreed to carry out protective conductor continuity and earth fault loop impedance tests as a minimum in accordance with 1.4 of guidance note 3. It is reasonable to assume that conductor details and insulation resistance etc. are unchanged as the circuits have not been altered. These would be re-evaluated at the next periodic inspection/test for the entire installation (which would stay at the same schedule as it was before the board was changed e.g. last done in 2011, net due in 2016 even though one of the DBs was changed and tested/inspected in 2013.

Is this considered a reasonable approach to DB replacements?
 18 September 2013 09:56 AM
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AJJewsbury

Posts: 17795
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An EIC definitely should be issued. As a minimum it needs to cover just the work done, so not necessarily downstream parts that are undisturbed and unaffected by the change. As insulation faults often occur at cable terminations I can see no logic to omitting an insulation test - without that it can't be shown that the re-working of the final circuit conductors hasn't introduced a few fault.
- Andy.
 18 September 2013 09:58 AM
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John Peckham

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Mazzy

Welcome to the forum.

Your contractors are talking bo***cks. The job requires an electrical installation certificate to be issued.Don't pay them until you get this. If they refuse then report them to the regulating body if they are a member of one.

-------------------------
John Peckham

http://www.astutetechnicalservices.co.uk/
 18 September 2013 10:10 AM
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OMS

Posts: 22864
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It's not that difficult as long as you grasp the concept that relevant information is contained within more than one document.

You need an EIC for the DB change. You need a schedule for that DB change that refers to the new protective devices. The existing PIR is then cross refeernced with that schedule.

So for example - if you've changed the MCB in Way 1 L1 then that is recorded on the EIC DB schedule. If you want to know what Circuit Way 1 L1 is/does, refer to the PIR which then also contains data on IR, number of points served etc

Simples

Your in charge, tell the operatives what you want - it's not a debate with them

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 18 September 2013 11:30 AM
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daveparry1

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Never heard such rubbish, of course it needs an EIC!

Dave.
 18 September 2013 12:11 PM
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MrP

Posts: 968
Joined: 24 March 2006

Mazzy welcome to the forum
One would question the competence of your contractor if their understanding of 7671 on compliance is in question therefore how can the integrity of the work completed be assured
Good luck buddy
I won't pay them to many bozoes out there

MrP
 18 September 2013 03:31 PM
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alanblaby

Posts: 868
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Originally posted by: mazzy2000

Their argument is that there is already a valid periodic report for the board and that the board is being changed from a 30 year old Ottermill quicklag style to a modern Schneider board with type B/C circuit breakers; therefore, it is safer.


Change a DB, then no certfication? What planet are you on?

The characterisitics of all the circuits affected have changed, so they all should be tested before energising them.
 18 September 2013 03:51 PM
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rocknroll

Posts: 9677
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Their argument is that there is already a valid periodic report for the board and that the board is being changed from a 30 year old Ottermill quicklag style to a modern Schneider board with type B/C circuit breakers; therefore, it is safer.


There is actually a lot of logic in that statement, you dont actually test the board but the circuits to the board and if on the last test they were within the bounds of Zs, IR etc then what is the problem, changing the board is not changing the parameters of the circuits but fitting a comparable unit that is in all extent better because it is more up to date using circuit breakers.

regards

-------------------------
"Take nothing but a picture,
leave nothing but footprints!"
-------------------------
"Oh! The drama of it all."
-------------------------
"You can throw all the philosophy you like at the problem, but at the end of the day it's just basic electrical theory!"
-------------------------
 18 September 2013 04:25 PM
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Parsley

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Originally posted by: rocknroll

Their argument is that there is already a valid periodic report for the board and that the board is being changed from a 30 year old Ottermill quicklag style to a modern Schneider board with type B/C circuit breakers; therefore, it is safer.




There is actually a lot of logic in that statement, you dont actually test the board but the circuits to the board and if on the last test they were within the bounds of Zs, IR etc then what is the problem, changing the board is not changing the parameters of the circuits but fitting a comparable unit that is in all extent better because it is more up to date using circuit breakers.



regards


Did the contractor who replaced the DB carry out the PIR in 2011?
Was it a driveby or did he jump of the train at each station along the route and get back on the next train when it arrived 15 mins later? what were the limitations?

If it's now protected by 30ma RCD protection then why botheranyway?

Regards
 18 September 2013 04:26 PM
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leckie

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So as OMS say then, issue the EIC recording the new CPD's, etc, fitted and record the test results from the previous PIR/EICR. if I was going to use the test results from another contractors certificate I would be stating that on the EIC.

Only problem is that in my experience a large percentage of PIR test results are created by someone's imagination so I think I would minimally want to do so sample tests and double check the limitations, etc on the PIR.
 18 September 2013 05:34 PM
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OMS

Posts: 22864
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You can imagine what you like about the previous PIR, the fact remains that it exists, it provides all the relevant parameters for the affected circuits excepting CPD characteristics.

There is no problem providing an EIC for the board change and refering to the relevant, valid and current PIR.

Let me ask you the question - If I give you an order to change the primary distribution switchboard in your local general hospital would you then be spending the next 3 months busily retesting every circuit in the hospital - because if you are planning that I can get you guys absolutely loads of work

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 18 September 2013 09:58 PM
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Zs

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Originally posted by: OMS

Let me ask you the question - If I give you an order to change the primary distribution switchboard in your local general hospital would you then be spending the next 3 months busily retesting every circuit in the hospital - because if you are planning that I can get you guys absolutely loads of work


OMS


Fantastic, because yes, I would. One by one. Unless my client elected to specifically exclude final circuit testing or elected that I copy test results across to the new forms and took the risk from me in writing.

When do I start?
 18 September 2013 10:50 PM
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Legh

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Originally posted by: Zs

Originally posted by: OMS

Let me ask you the question - If I give you an order to change the primary distribution switchboard in your local general hospital would you then be spending the next 3 months busily retesting every circuit in the hospital - because if you are planning that I can get you guys absolutely loads of work

OMS


Fantastic, because yes, I would. One by one. Unless my client elected to specifically exclude final circuit testing or elected that I copy test results across to the new forms and took the risk from me in writing.

When do I start?


Ditto... I fancy a 6 month jaunt in a hospital honing my skills at a reasonable salary, of course....

Legh

-------------------------

http://www.leghrichardson.co.uk

de-avatared
 18 September 2013 04:19 PM
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AJJewsbury

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more up to date using circuit breakers.

It depends on what's replacing what. Change from a 5A cartridge fuse to a 6A C type MCB and the max permitted Zs might change from 8.4 Ohms to 3.09 Ohms (for 0.4s disconnection time). Changing from a 5A type 1 to a 6A type B moves from 9.27 to 7.42.

I don't think there are any grounds for a blanket 'if it's newer it must be better under all circumstances' belief, especially somewhere like a railway station where you might be looking at unusually long circuit lengths.

- Andy.
 18 September 2013 10:19 PM
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AJJewsbury

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record the test results from the previous PIR/EICR

I'd suggest that some new tests would need to be done to prove the new work is correct - i.e. continuity, polarity, insulation test - as these could have been undermined by errors in the new work. For continuity/polariy that might need a wander lead to the 1st accessory on each circuit. What the previous PIR/EICR can give you are the circuit characteristics beyond (downstream) of the point of change - i.e. max R1+R2, which provided the connections have been soundly and correctly reinstated (as proved by the continuity/polarity tests) and the circuits neither shortened or extended then there's no need to find the end of each final circuits and verify R1+R2 or Zs from there.

So in a test results recorded should be from fresh tests, but unchanged circuit characteristics (i.e. things that could have come from a design rather than necessarily a test) can come from previous documentation.

- Andy.
 18 September 2013 10:29 PM
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John Peckham

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OMS


"You can imagine what you like about the previous PIR, the fact remains that it exists, it provides all the relevant parameters for the affected circuits excepting CPD characteristics."

You would need a huge leap of faith and trust to accept that as a fact unless you measured and recorded those results yourself because as we know most PIRs/EICRs are fabrications produced by half wits.

As for changing a primary distribution board in a large hospital no you would not test all the final circuits from the sub boards but you would test the distribution circuits to those sub boards from the primary board. That question is answered in the ESC Guidance in question Q2.15.

Also you would want to inspect and test the installation after the board has been changed because the best of people make mistakes. I tested an installation recently after a board change and found a reverse polarity on a circuit where the cable terminations had been reveres ed on an RCBO. The very competent and diligent electrician was mortified when I pointed out the error.

A colleague of mine did a periodic on a school 5 years after all the DBs had been changed by an NICEIC Approved contractor. He found most circuits were unearthed because the original circuits relied on the conduits as a CPC which were connected to the old DBs. The conduits had been cut back and dropped in to a plastic trunking above each DB hence unearthed circuits. Also every board was full of Type D breakers. There was an EIC for the installation of the boards completed by the contractor with satisfactory EFLI results for each circuit.

I think we all agree an EIC is needed? I don't think I would agree 1. To use other people's test results. and 2. Even if I had carried out a PIR I would sign off an EIC without ANY further testing.

-------------------------
John Peckham

http://www.astutetechnicalservices.co.uk/
 19 September 2013 06:33 AM
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normcall

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Doctors and nurses come to mind!

-------------------------
Norman
 19 September 2013 07:07 AM
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davezawadi

Posts: 4259
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Mazzy
The question to ask here is why they do not want to issue a certificate? Unfortunately the usual answer is somewhere between "can't be bothered" and "I'm not taking responsibility for my work". Both of these show a dreadful lack of professionalism and competence.

It is likely that they do not want to do much testing, but this is not a problem really, they are lazy and want to knock off early!
My method would be to verify a couple of the circuits on the PIR, to see if it is genuine (sockets as this is easy). If all is well the it is probably OK to rely on the PIR circuit numbers; If not then you do the lot! As I have said before, I would test every point with a loop tester, and each circuit when disconnected for insulation to earth. Circuit R1+R2 values need to be checked and matched to the new breaker type. Fill out the form, job done. You have your EIC.

I concur with all the comments below, but this sort of thing is happening all the time. You need to make a complaint to the scheme provider, not that it will do much good I'm afraid.

-------------------------
David
BSc CEng MIET
 19 September 2013 07:32 AM
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leckie

Posts: 4705
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I thought R1+R2 tests were only an actual requirement for initial verification?

The test is not in the list of test for EICR's in GN3 as far as I recall. I would think it would be optional and only ELI test is required even though this is not an EICR but an alteration. Or whichever way is the easier in the circumstances.
 19 September 2013 07:53 AM
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dickllewellyn

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Personally I think the meeting of two opposite extremes will work just nicely. You have the previous PIR, so that helps to get the ball rolling. When putting the board back together, I personally feel its lazy not to make off all the earths, croc to that, and insulation test to lives and neutrals as they are terminated. These readings can be compared to those on the PIR. If they are miles out and look made up, the alarm bells start to ring and further testing can be carried out more diligently. If you are getting readings such as for example 29megohms consistent with the PIR, the clues would suggest they're not made up! Wilst terminating, if there are any rings, it seems daft for the sake of a couple minutes not to test their continuity, and again compare the resistance with the PIR. If there are any vast differences, again you know where to start looking.

With circuits insulation tested and terminated, assuming the r1r2 and Zs readings on the PIR are within parameters for new protective devices, I would personally fire up circuits one at a time, checking they are in fact what the PIR said they were, and running round a few accessories with a loop tester verifying polarity and Zs. A certificate can then be produced with a combination of results taken on site, and results gained from the PIR.

That's how I'd do it.

Now. About this hospital job?!

-------------------------
Regards
Richard (Dick)

"Insert words of wisdom and/or witty pun here"
 19 September 2013 03:15 PM
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OMS

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OK - it appears then you are all making the fundamental assumption that the PIR will be a fabrication and the installer is a moron

Now I'm sure that's all true exept for you, as individuals.

I guess irony doesn't factor high on your agendas.

My point was that changing the DB, in an installation that has a current PIR, dos not place an obligation on the installer for works outside of his control - hence my comments about the hospital and despite the collective belief that "everyone else" is a complete charlatan.

It pays not to get too fixated on the numbers - they get in the way of good engineering judgement I find.

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 19 September 2013 05:22 PM
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leckie

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So OMS, are you suggesting that the PIR test results are simply transferred to the EIC or that the test results are omitted?

And if the results are simply to be transferred do you not consider that some sample testing should be carried out to check the PIR recorded results?

I expect it depends on the situation, and what you are signing for. If I had carried out a EICR and was asked to replace a DB I wouldn't expect to retest every item that was carried out during the EICR. If you do an EICR prior to carrying out a con unit or DB change do you retest everything? I don't, but I redo zsdb, polarity and earth loop to a previously check socket and anything else I think is required.

But if I was changing a board after someone else had done a pir, and I was signing for the design, construction and T&I then I would want to confirm minimally a sample of the test results. I don't think all contractors are rubbish, but many are inconsistent. They are only as good as there worse man. The electrical industry is not just domestic or large industrial, it's a mixture, large, small, complex, basic, old install, modern installs. Each needs to be assessed individually.

Well that's what I think!
 19 September 2013 05:42 PM
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iie62478

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The obvious answer lies in what does the Network Rail Standard say for this work/contract.

Any work on a station must comply with the necesary standards irrespective of who let the contract NR or Train Operating Company.

-------------------------
Are we all in this together???
 19 September 2013 06:11 PM
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OMS

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Originally posted by: leckie

So OMS, are you suggesting that the PIR test results are simply transferred to the EIC or that the test results are omitted?

No - read what I said again. You provide the EIC with relevant information and test data including a schedule of the new protective devices.

This is then supported by the PIR (or EICR) - th circuits haven't changed have they ?


And if the results are simply to be transferred do you not consider that some sample testing should be carried out to check the PIR recorded results?

Are you appointed to police the PIR sector then - you need to test what you feel is appropriate given what you see in front of you.


I expect it depends on the situation, and what you are signing for. If I had carried out a EICR and was asked to replace a DB I wouldn't expect to retest every item that was carried out during the EICR. If you do an EICR prior to carrying out a con unit or DB change do you retest everything? I don't, but I redo zsdb, polarity and earth loop to a previously check socket and anything else I think is required.

So if you've done the PIR, it's fine to use it - but not if it was done by anyone else ?


But if I was changing a board after someone else had done a pir, and I was signing for the design, construction and T&I then I would want to confirm minimally a sample of the test results. I don't think all contractors are rubbish, but many are inconsistent. They are only as good as there worse man. The electrical industry is not just domestic or large industrial, it's a mixture, large, small, complex, basic, old install, modern installs. Each needs to be assessed individually.

Wasn't that my point


Well that's what I think!


Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 19 September 2013 06:33 PM
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kj scott

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We still don't know the circumstances of the work. Is the OP a client, manager, contractor, in-house client etc. This would all change the documentation needed.

In the vast majority of circumstances an EIC would be required, and relevant testing completed; but not a further EICR; or testing to the extent of a whole new installation; after all it is a DB change, with previous records

Also contrary to RnR comments; in this case it appears to be the installers that want to avoid the further testing and documentation; more like the realities of most installations.
 19 September 2013 06:42 PM
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OMS

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And as I've said before, you can't test quality into an installation - you have to design it in and then build it in.

Too much focus on the numbers and the paperwork often masks the real issues and the real dangers.

None of the testing tends to find the real problems.

Regards

OMS

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 19 September 2013 06:53 PM
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kj scott

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I would agree that testing and an inspector with tunnel vision to produce numbers is counter productive; however inspection is very effective at finding the real problems and the OP was a question about the documentation required.
Aside from this the misdirection of inspectors to generate reams of paper containing numbers was caused by BS 7671 and IET guidance documents.
 19 September 2013 07:40 PM
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OMS

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LoL - and not by NICEIC (god bless em) then Keith

I agree you need inspection before testing to have any value

Regards

OMS

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Let the wind blow you, across a big floor.
 19 September 2013 09:33 PM
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leckie

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Originally posted by: OMS

Originally posted by: leckie



So OMS, are you suggesting that the PIR test results are simply transferred to the EIC or that the test results are omitted?



No - read what I said again. You provide the EIC with relevant information and test data including a schedule of the new protective devices.



This is then supported by the PIR (or EICR) - th circuits haven't changed have they ?




And if the results are simply to be transferred do you not consider that some sample testing should be carried out to check the PIR recorded results?



Are you appointed to police the PIR sector then - you need to test what you feel is appropriate given what you see in front of you.





I expect it depends on the situation, and what you are signing for. If I had carried out a EICR and was asked to replace a DB I wouldn't expect to retest every item that was carried out during the EICR. If you do an EICR prior to carrying out a con unit or DB change do you retest everything? I don't, but I redo zsdb, polarity and earth loop to a previously check socket and anything else I think is required.



So if you've done the PIR, it's fine to use it - but not if it was done by anyone else ?





But if I was changing a board after someone else had done a pir, and I was signing for the design, construction and T&I then I would want to confirm minimally a sample of the test results. I don't think all contractors are rubbish, but many are inconsistent. They are only as good as there worse man. The electrical industry is not just domestic or large industrial, it's a mixture, large, small, complex, basic, old install, modern installs. Each needs to be assessed individually.



Wasn't that my point





Well that's what I think![IMG][/IMG]




Regards



OMS

Blimey I think I've upset someone
 20 September 2013 10:15 AM
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OMS

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Not at all - and my apologies if it came across that way - it's just a debate and we all have equally valid viewpoints from our own perspective.

All I was trying to say is that often the industry has this view that anything they're given is not to be trusted and must be repeated and repeated and repeated before any degree of safety can be reasonably practicably assured.

I hear lots of people talking about IR values all being the same at greater than 299Mohm or 599mohm or 999Mohm and I see also a fixation on actual Zs values to a totally unwarranted degree of accuiracy that is an oder of magnitude different to what credible Zs values are in reality.

As technical people, we spend our lives dealing with probablity (in the electrical sector, isn't that exactly what diversity as an example is all about). However, we don't seem to be able to take the same thinking approach when it comes to inspection and testing.

As I said, if we actually had less focus on the numbers as a form filling exercise and more focus on what a few basic tests supported by competent inspection actually achieves, then the concept of using a credible PIR to support a simple DB change without testing to death every circuit involved becomes more reasonable don't you think.

As I mentioned to someone recently - if asked to do a board change on an installation that had been tested by say John Peckham or the BOD in the last 12 months how far would you go. The answer, predictably was inconclusive, but could probably be distilled into a willingness to accept the PIR data are correct and quite correctly, could be used, subject to a few tests for "self checking" aspects such as polarity etc - most of which would be relevant to the DB anyway.

Take a look at Dick Llewellyns post for what would be considered reasonable ?

So, my apologies if some of the previous came across the "wrong" way - I was just looking at this with less of a "boots on the ground" approach and more as an overview of a principle - let's not forget that BS 7671 doesn't draw the conclusion that previous documentation is a work of fantasy - how could it.

Regards

OMS

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Let the wind blow you, across a big floor.
 20 September 2013 10:54 AM
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Parsley

Posts: 1383
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Unfortunately I think the NIC guidance and I&T software providers have a lot to answer for. But it's up to contractors to see through the mud and take responsibility for their actions.

I received an EIC from an NIC approved subcontractor this morning for a simple new final circuit up to the isolator of an external AC unit.

poorly completed EIC a quick review pointed out the following errors.

Supply characteristics
Max demand N/A
protective measures against elec shock N/A

Schedule of items inspected
Basic protection placing out of reach and obstacles box ticked
cables and conductors erection methods box N/A

Electrical separation for one item of equipment box ticked.

Serial numbers of tester for IR, continuity N/A.

The DB where the final circuit was taken from submains details not entered.
The list goes on, the company has been NIC AP for a long time.

Regards
 20 September 2013 11:57 AM
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OMS

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For sure - but is it dangerous ?

Regards

OMS

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 20 September 2013 02:33 PM
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Parsley

Posts: 1383
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Originally posted by: OMS

For sure - but is it dangerous ?



Regards



OMS


I'm sure the install is absolutely fine.

A big industry has been built on I&T and other forms of compliance. If you've got to do it, then you should do it to the best of your ability.
It's like O&M's with loads of generic manufacturers info that doesn't relate to the what's installed on the job but used to fill up the binder.
And record drawings that are still the original tender/construction ones.

Regards

Regards
 20 September 2013 03:31 PM
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leckie

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Ah, OK OMS, I was being over sensitive. Some of you guys (and girls), are such brain boxes that it's easy to get an inferiority complex!

Actually I think what Dicks post said is pretty much exactly what I said anyway

Regardless, I believe that what I do on each contract is usually appropriate the the existing conditions based on the info to hand. I haven't killed anyone or burnt a building down for ages.
 20 September 2013 04:18 PM
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OMS

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I haven't killed anyone or burnt a building down for ages


Nor me, and I guess it's true to say that very few are killed and not many buildings burn down.

So, just perhaps, all these horror stories about crap form filling are just a smoke screen really, the underlying situation being much, much safer than perceived (or actually promulgated by certain industry parties).

Regards

OMS

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 20 September 2013 07:39 PM
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sparkingchip

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Then there is the design issue that everyone seems to like to forget.

A new installation certificate covers design as well as installation and the inspection & testing. At some point someone has specified the equipment to be installed presumably basing their design on the periodic inspection report already produced rather than what was already installed, so it may not be a like for like swap if existing circuit protective devices were inappropriate, there must have been something wrong with the original board or else why swap it?

So your guys are trying to get away without signing off the design, erection and verification of the new equipment hardly professional is it?

Andy
 20 September 2013 07:59 PM
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kj scott

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It's not that the condition for fire doesn't exist; usually due to poor standards of design and installation; it is more that they rarely are realised.
I have been working in a small shop unit this week and have found at least 25 instances of burning to cables and building fabric. These have persisted over a period of 20 plus years in a 200 year old building; but it's still here.
That said it doesn't make the design correct, or the standards of installation and inspection; but testing would have found nothing.
 20 September 2013 01:36 PM
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Legh

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hence my comments about the hospital and despite the collective belief that "everyone else" is a complete charlatan.


Appologies....I thought that was a genuine offer of some excellent inspection and testing work with top rates of renumeration + benefits ....

Doctors and nurses come to mind!


Although i piggy backed my interest onto Zs' reply I think you could say they were separate enquiries.....

Legh

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de-avatared
 19 September 2013 08:08 AM
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kj scott

Posts: 2144
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Originally posted by: mazzy2000

I know this topic has been discussed previously, but I am trying to gauge opinion a bit further.



My team of electricians recently carried out a distribution board replacement feeding circuits at a small railway station and in their opinion, it does not require an electrical installation certificate. My interpretation of the regulations is that this work should have been certified in accordance with 610.6 as it is an alteration in accordance with 610.4.

By 'team of electricians' do you mean in house, or contractors?
Are other methods of record used?
How would you record compliance with EAWR?


There are two types of certificate, but the notes on the minor works cert preclude it from being used for DB changes; therefore, an electrical installation certificate must be issued together with a full schedule of inspections and tests. This would include relevant tests/inspections on all the final circuits, even though they have only been disturbed at the distribution board.

You are correct, the Electrical installation certificate would be the most appropriate form.

Their argument is that there is already a valid periodic report for the board and that the board is being changed from a 30 year old Ottermill quicklag style to a modern Schneider board with type B/C circuit breakers; therefore, it is safer.

The periodic inspection report does not take account of the changes made, but will be used to contribute to the installation records.

Another agrument for issuing the certificate would be for recording the differences between the two installations, even though they have likely been improved e.g. main switch characteristics, different circuit breaker characteristics (5A to 6A, 30A to 32A etc.). Also, this cert is signed off to indicate that the new installation has been designed, constructed and inspected/tested in accordance with 7671.

All information that could reasonably be expected in the certificate.

As a compromise, they have agreed to carry out protective conductor continuity and earth fault loop impedance tests as a minimum in accordance with 1.4 of guidance note 3. It is reasonable to assume that conductor details and insulation resistance etc. are unchanged as the circuits have not been altered. These would be re-evaluated at the next periodic inspection/test for the entire installation (which would stay at the same schedule as it was before the board was changed e.g. last done in 2011, net due in 2016 even though one of the DBs was changed and tested/inspected in 2013.

And what form of document will they use to record this information?

Is this considered a reasonable approach to DB replacements?


The extent of inspection and testing required for a DB change will vary on a number of factors, including changes to the installation characteristics, quality of the existing installation, existing records and standards of both past and future maintenance.
What is the extent of the alteration work?
Who is responsible for the design of this alteration work?
Who is responsible for the construction?
Who is responsible for the inspection and testing?
How are these people recording their individual responsibilities?
How will the new distribution board revised circuit details be recorded?
Inspection of the work is also necessary, how will this be recorded?
 19 September 2013 08:27 PM
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mazzy2000

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Many thanks to all who have contributed to this discussion, it has been very helpful to get the opinions of different people with knowledge & experience of this subject. I will certainly be using this forum to bring other topics to the table.

Just to clear up some of the questions/enquiries, I work in the organisational Engineering department & the electricians are part of our in house maintenance department. We use other forms of recording/documenting work e.g. signed work orders/job cards, but I don't believe these are sufficient in meeting what is required by the regulations as they do not document system characteristics. It is just a high level record of what was done, when it was done and who done it etc.

The electricians are now going to do an EIC for the board with continuity & EFLI tests for each final circuit as a minimum. If inspections/tests reveal the need for other tests, these will be carried out as required. We also have the PIR for records on the condition of the rest of the installation.

Once again, thanks for the help.
 19 September 2013 09:31 PM
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dickllewellyn

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Well done Mazzy. Sounds like you've got the right solution.

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Richard (Dick)

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