High Ze reading fails EICR

Maarel · Sep 29, 2023

Hello there. I've been looking around here and found some conflicting information. I have a question if I may ask. I had an electrician come over to perform an EICR, and all the installations were in good nic. However, he said that the Ze measurement was 14.5 Ohms on a TNS system, so he refused to sign it off. I've arranged for the DNO to investigate, and they say that our stairwell need to be rewired due to outdated wiring, which would take them 1-2 months. The issue is that I need a valid EICR in a maximum of two weeks, and I'm wondering if there's any chance he could have signed this off as satisfactory, considering that the dwelling's electrical installation is protected by an RCD, which, if I understand correctly, would isolate the system within the required 0.4 seconds in case of an Earth fault.

pc1966 · Sep 30, 2023

kropaske said:
Whether satisfactory or not, would you leave this installation live and walk away?

Without knowing enough about the installation the question of if it could be left live is not answerable.

Most probably it can, as this is C2 sort of risk and ADS would work at least once. There might be other risks such as a ground floor flat with touchable class I lights outside on the at-risk CPC system, etc. But the owner & occupier(s) need to know of this, and also what mitigation steps are needed (if any) until it is fixed properly.

kropaske said:
Why not for example make it satisfactory and schedule weekly visits to verify that connection it's still there untill repair is complete. Would that not be better then just give unsatisfactory and walk away.

An EICR is a bit like a MOT, a summary of the system at the time of the test being satisfactory or not. Here it is not.

What to do next is a separate issue. As far as I understand from the OP's posts, the electrician is refusing to sign off a satisfactory just now but is willing to come back and do so after that is addressed, which is all right and proper. It seems the pressure for "satisfactory" now comes from some other aspect, as @Mike Johnson suggested probably for letting reasons.

baldelectrician · Sep 30, 2023

There is no effective means of earthing

We get this occaionally and SPEN are quite quick to fix things- although they took a month to fix one in Galston (they assumed the whole install had RCD by glancing, despite more than one property off the supply)

I raised a complaint with SPEN but it went nowhere.

Maarel · Sep 30, 2023

My apologies, let me get this right. The electrician is refusing to issue an EICR, I need the report either if it is satisfactory or not. It’s not for letting purposes but for an application for license I need for next August. The deadline is approaching and if I don’t get it sent in I would have to wait over a year. In order to apply I need all documents. I would have sent in the unsatisfactory EIRC and by the time they process my application Earth will be sorted and Ze retested to satisfactory.

westward10 · Sep 30, 2023

There is nothing to stop them issuing the EICR.

baldelectrician · Sep 30, 2023

Maarel said:
My apologies, let me get this right. The electrician is refusing to issue an EICR, I need the report either if it is satisfactory or not. It’s not for letting purposes but for an application for license I need for next August. The deadline is approaching and if I don’t get it sent in I would have to wait over a year. In order to apply I need all documents. I would have sent in the unsatisfactory EIRC and by the time they process my application Earth will be sorted and Ze retested to satisfactory.

Just request the unsatisfactory EICR.

Probably better to do it in writing / email etc

Maarel · Sep 30, 2023

ok I pressed he to send it over but this does not look right, I’ve seen he haven’t put in values for R1 R2 and also no test values for RCD, please see attachment. Is this is how the report should have been done or this guy is a cowboy? Also there’s not any c1, c2 or c3 codes with the observation sheet. When he was here he said everything is ok and he have put in notes that installation is ok but pending rewiring in the stairway. He said he’s registered with niceic and that was the reason I choose him. Please any opinion or I am overthinking?

[ElectriciansForums.net] High Ze reading fails EICR

westward10 · Sep 30, 2023

That schedule is totally incomplete.
RCD types, continuity for the ring finals which I assume you have, R1+R2, RCD readings all N/A when that should not be the case.
The Ze should be a Code 2 minimum.
I would be questioning this.

SJD · Sep 30, 2023

Apologies if I missed it, but how long was the electrician on site? To complete the above table of results, they'd need to be there around half a day (assuming 1 person).

Maarel · Sep 30, 2023

Ok thanks, appreciate you’re taking time to answer.

Westward10 I will confront him about the luck of readings.

He was there for around 2 hours. I’ve seen he tripped the RCD with his diagnostic tool. I seen he was plugging he’s machine into sockets. However, I don’t believe he did any insulation test or r1 r2 for lighting circuits as I was around and didn’t see him taking off any of the accessories.

Also the report says water mains and gas are bonded but I just checked and there are no water main bond due to the incoming pipe is made of PVC

ipf · Sep 30, 2023

Just reading #6
''He conducted R1+R2 tests for all circuits and mentioned that the resistance readings were acceptable. He also tested the RCDs, and all the tests passed, as did the insulation resistance tests''.
You, or he, seem to know what's involved regarding the tests.
It seems pretty obvious that it is a sub main problem of some sort......then again, looking at those results, who knows?
It would be interesting to know where the sub mains to each flat are fed from and how the splitting occurs.
I'm wondering, here......
What 'instrument' did he plug in.... a socket tester for polarity???
How much did he charge for the supposed EICR?

Rockingit · Sep 30, 2023

OK, so issues of this particular inspection scenario aside, when is an Earth not an Earth?

Many have suggested (rightly so) a temporary lashup with a rod and S-Type to TT it until it gets fixed. If the 'new' rod has an Ra of 50-60-70Ω that's considered entirely fine as it's under the magic 200Ω but is clearly worse than the original value of 15Ω. Yet we say we can't rely on an RCD for fault protection due to 'lack' of an Earth. At least the 15Ω gets you a pefc of 16A which clearly will take out an RCD.

davesparks · Sep 30, 2023

Maarel said:
My apologies, let me get this right. The electrician is refusing to issue an EICR,

Rockingit said:
OK, so issues of this particular inspection scenario aside, when is an Earth not an Earth?

Many have suggested (rightly so) a temporary lashup with a rod and S-Type to TT it until it gets fixed. If the 'new' rod has an Ra of 50-60-70Ω that's considered entirely fine as it's under the magic 200Ω but is clearly worse than the original value of 15Ω. Yet we say we can't rely on an RCD for fault protection due to 'lack' of an Earth. At least the 15Ω gets you a pefc of 16A which clearly will take out an RCD.

But it is unknown as to why an earth that would have been under 0.8 ohms has become 15 ohms, it could be a solid 15 ohms or be very unstable.

An earth rod would likely be higher yes, but it would be stable and a known quantity.

Rockingit · Sep 30, 2023

davesparks said:
But it is unknown as to why an earth that would have been under 0.8 ohms has become 15 ohms, it could be a solid 15 ohms or be very unstable.

An earth rod would likely be higher yes, but it would be stable and a known quantity.

That's a fair point, although you'd think that the DNO would have checked several times before committing to a renewal?

pc1966 · Sep 30, 2023

Rockingit said:
That's a fair point, although you'd think that the DNO would have checked several times before committing to a renewal?

If it is 80+ year old cable and earth failing they are unlikely to check why, beyond a quick check at the cutout, so just proceed to schedule replacement?

Maarel · Sep 30, 2023

ipf said:
Just reading #6
''He conducted R1+R2 tests for all circuits and mentioned that the resistance readings were acceptable. He also tested the RCDs, and all the tests passed, as did the insulation resistance tests''.
You, or he, seem to know what's involved regarding the tests.
It seems pretty obvious that it is a sub main problem of some sort......then again, looking at those results, who knows?
It would be interesting to know where the sub mains to each flat are fed from and how the splitting occurs.
I'm wondering, here......
What 'instrument' did he plug in.... a socket tester for polarity???
How much did he charge for the supposed EICR?

I was told about the r1 r2 being acceptable but after doing some research I’m starting to doubt if he did that for all circuits as I didn’t see him taking off any light fittings. He plugged in his megger, the same he used to trip the RCDs.

I was charged £160 for the job