Find electrician to trace earth leakage

[naylorpd]

OK, so this is a follow-on to my thread about unsatisfactory EICR.

There is a big inconsistency in that the EICR reports all the L-E IR as >100 Megs, but the inspector also comments about earth leakage in two ring mans and one lighting circuit. This seems to be stopping me from replacing the CU and related C2 problems because RCDs will trip constantly (as I understand it).

The guy that did the EICR advised that the earth leakage was measured and the readings were off the scale, and he just didn't change the software defaults on IR (I interpret... he didn't check IR at all).

So my plan of action is to engage someone else to trace the faults, ideally on an hourly rate (probably plus call-out). I need to find that someone (in Reading/Tilehurst) - preferably experienced in fault-finding and not just installation.

What qualifications and experience do I need to look for and ask about? Which is likely to be more suitable, NAPIT or NICEIC?

What's involved in doing this kind of fault-finding? Is it likely to mean disconnecting all the sockets and light switches to test the bare cables?

Thanks

 

[Jim_e_Jib]

If he's IR tested the USB sockets L-E at 500V it could be nasty ...
Testing USB wall mounted sockets - https://uk.megger.com/electrical-tester-contractor-edition/june-2015/testing-usb-wall-mounted-sockets

I do always wonder if there is a reason why the SMPS in these sockets isn't fed from the switch. It seems to be a simple solution to the problem and means you're not leaving the power supply permanently on.

 

[Deleted account]

But it comes back to what criteria I can use to assess whether someone is going to be competent....
- NICEIC?
- NAPIT?
- Checkatrade?

I'm embarased to say you can't rely on any of these. You will get good and bad in each of these companies.
I'm part of niceic and know they inform you whether a contractor has relevant qualification in EICR. Not sure about others. Unfortunately even getting a contractor with this qual does not nessisarily mean getting a good experienced spark.

Due to shortage of sparkies in the industry it is flooded with inexperienced or undertrained or miss trained sparks.

Sorry not very useful, but true. Alway go with word of mouth if you can.

I think you have done everything you can to get a decent spark. He is registered and he was recommended by your agent.

 

[naylorpd]

Naylorpd
A video you may find of interest

Yes, interesting in many ways, including seeing an earth leakage test and what caused it. I don't think I've run a nail through anything!

The comment in the last 30 seconds is about where I'm at...how do you know they are not competent if they have a NAPIT number...how do you protect yourself against that...

 

[Deleted account]

Yes, interesting in many ways, including seeing an earth leakage test and what caused it. I don't think I've run a nail through anything!

The comment in the last 30 seconds is about where I'm at...how do you know they are not competent if they have a NAPIT number...how do you protect yourself against that...

Post 15 dustydazzler gives best advice there is.

 

[naylorpd]

If he's IR tested the USB sockets L-E at 500V it could be nasty ...
Testing USB wall mounted sockets - https://uk.megger.com/electrical-tester-contractor-edition/june-2015/testing-usb-wall-mounted-sockets

As he doesn't say that he disconnected the USB sockets, if he did the test he could have fried them? So I should be hoping that he didn't actually do the IR test?

That raises another whole issue - these USB sockets are very readily available at all electrical stores, DIY stores etc. but can't survive a standard IR test at 500V. I bet the average homeowner doesn't know that.

 

[littlespark]

Its not just USB sockets that can get fried.... Electronic dimmer switches, PIR sensors, LED lights... nothing with electronics like having the 500vDC pumped through it.

 

[Dustydazzler]

I learnt this the hard way and fried part of a pcb in a brand new boiler

Once bitten twice shy

 

[The Ghost]

Let us rewind a moment to the beginning. You say you made clear that you wanted a CU change. It is common practice to check earthing arrangements and leakage as a minimum prior to changing. As if there are earth leaks we all know this will lead to tripping of the RCD and the fault will have to be rectified. They were no doubt essentially assaying the state of your circuits prior to that change and that was the main thrust of their inspection. Having established there was earth leaks I think I would have done IR tests to establish to what degree and where exactly the leakage was. So normally we would test then split the circuit in half and test each half and then a quarter until we had narrowed down what part or maybe all of the circuit is damaged/causing such readings. They did put F.I. for the problem of earth leakage which is saying at a certain point they would investigate. In doing an EICR we are only to inspect and report the condition of the installation. We are NOT to rectify. This means any remedial work or F.I. would be done after the report and reliant on the instructions of the person ordering the work (you) If you are unsure of the skill of the person doing the EICR as I said you ensure probity by getting another party to do the remedials and thus cross check. I personally would give the professional courtesy of the benefit of the doubt and assume the IR testing would be done later in this case when you ordered the remedials. They obviously assumed they would be getting the remedial work and left it as a work in progress. I think that is the best gloss I can put on it.

 

[Deleted member 26818]

Not sure that’s correct Vortigern.
The other thread indicates an EICR was conducted and the recommendation is for a new CU (among other things).

 

[naylorpd]

I knew I needed a new CU because the old one has MCBs and not RCDs. Should I have done that before the EICR?

For better or worse, this saga has thrown up the IR/earth leak problem that I didn't know about before.

 

[Deleted member 26818]

I knew I needed a new CU because the old one has MCBs and not RCDs. Should I have done that before the EICR?

For better or worse, this saga has thrown up the IR/earth leak problem that I didn't know about before.

Thing is, the EICR (apart from the erroneous comment about requiring an RCD for fault protection) does not indicate a new CU is required.
Code C3 just means improvement recommended, not a dangerous situation.
I would be very disappointed with the FI code, as it’s basically saying they’ve conducted an Inspection and now recommend a proper Inspection be conducted.

 

[Pete999]

I knew I needed a new CU because the old one has MCBs and not RCDs. Should I have done that before the EICR?

For better or worse, this saga has thrown up the IR/earth leak problem that I didn't know about before.

Disagree with your first paragraph.

 

[westward10]

Go back to the original contractor and say you are not happy with the Report. The statement about high leakage contains no valuable content for you to proceed and it is not clear whether insulation resistance tests were done.

 

[The Ghost]

Should I have done that before the EICR?

No as the contractor must test anyway before putting in a new CU as the possibility of pre-existing faults would trip the RCD and then you are at square on having to do tests to find out the fault. Anyway surely you were due a new EICR?

 

[spark 68]

If, and I mean if the IR tests were carried out correctly and showed no appreciable faults then where does the "earth leakage off the scale" come from ?
What I have seen done, is a spark/s with their shiny new earth leakage meter then proceed to clamp the MEC with it (instead of just the tails) especially on a PME system, and see several Amps showing! this however can be normal as PME systems notoriously can have plenty of Amps of circulating currents sloshing around on the incoming Earthing conductor, me and Tony had quite an in-depth discussion about this several years ago.
This is of course separate to other issues with the EICR in general, as others have said get a second opinion.