Insulation resistance test issue

[naylorpd]

Back in 2013 I had a Domestic Electrical Installation Condition Report done on my rented property - nothing horribly major but one thing I didn't understand...

I had a C3 code for "0 ohms readings for I.R test for sockets & lighting (unable to remove all loads sockets, lighting had electronic dimmers)"

I didn't do anything about this at the time, but 5 years on I'm thinking that cables don't improve with age so perhaps I should get the insulation testing done this time.

So...
1) Yes I have some electronic dimmers, so how do I overcome this? Do they need to be taken off to do the IR testing? And do I need to put ordinary switches back on temporarily, or can I just unscrew the live cable, do the test and put the switches back?
2) I don't understand how sockets would have been a problem, surely it's easy enough to just unplug everything. Was the tester just being lazy, or is there another problem that isn't really being explained?

Thanks
Phil

 

[ChrisElectrical88]

Which was the 0MOhms recorded? L-N, L-E or N-E?

If L-N then it is more than likely the dimmers, however this shoukd have been labelled Lim and a limitation agreed before hand if all dimmers were not to be rwmoved frpm the circuit prior to testing.

 

[Silly Sausage]

I didn't do anything about this at the time, but 5 years on ...

You're almost due another Inspection

 

[Deleted member 105166]

If not possible to remove something that may be damaged (lighting transformers, 13a sockets with USB, etc) by a 500V Insulation Resistance test, your electrician will common L&N and test to E at 500V and then test L to N and L to E at 250V

 

[naylorpd]

Report attached, I have:
Lim on most L-N
0 on all N-E and some L-E

Scope would have been agreed by my agent, I doubt if they would have understood what it means anyway. I doubt if dimmers were removed.

Would that also apply to switches with PIRs built in (garage)?

Thanks

 

[naylorpd]

You're almost due another Inspection
Get someone who knows what they're doing next time.

To know if someone knows what they are doing, you need to have a pretty good idea yourself...that's why I'm asking

 

[ChrisElectrical88]

Any chance of a copy of Page 2 which should be deviations.

 

[johnduffell]

Deviations are made by the designer so would be on the eic, limitations are made by the eicr.

 

[naylorpd]

Chris - attached. Main job is to replace the CU, mains tails and bonding all part of same job in the garage, I think. I've dealt with the small things. This is item 7.

Tony - back in 2013 I wouldn't have had any USB sockets, but do now! Some fluorescent lights (the big old tubes) with starters etc back then, but now some LED strip lights.

This is sounding like just the IR test is shaping up into a big job if I have to disconnect all the dimmers, USB sockets, LED lights etc.?

 

[ChrisElectrical88]

Im not after the limitations or i woukd be asking for page 1. Im after the deviations that he has found on his EICR.

 

[naylorpd]

Im not after the limitations or i woukd be asking for page 1. Im after the deviations that he has found on his EICR.

Limitations were :
- Unable to disconnect all connected loads to carry out L-N insulation resistance testing,
- No lifting of floor boards or inspection of loft space

Thinking about it, "Unable to disconnect" seems a strange thing to say. Of course it would have taken more time (which I'm sure would have been charged) but I don't see why he would have been unable to do it.

 

[ChrisElectrical88]

IR Test should have been done by linking the L&N and testing to earth in this case IMO. By the looks of all the neutrals been 0, he hasnt bothered to disconnect the neutrals when IR testing.

Not. Picked up the high r2 reading on one of the rings or the oversized protective device on the water heater (although if only a fused spur would be a C3). Low IR in my book is a C2 as it is potentially dangerous.

 

[Octopus]

I would say the N-E IR was probably done with the main switch on !

How much were you charged for this "report"?

 

[ChrisElectrical88]

I would say the N-E IR was probably done with the main switch on !

How much were you charged for this "report"?

100% Main switch on with no neutrals disconnected. Pee poor.

 

[Wilko]

It might just be because of the pain relieving liquids I've been consuming - but recording Zero Ohms to E makes me think he's done something silly with the testing.
Edit - darn, too busy drinking to type faster

 

[Silly Sausage]

I would say the N-E IR was probably done with the main switch on !

How much were you charged for this "report"?

Maybe they have TNC installations in Azerbaijan?

 

[johnduffell]

Im not after the limitations or i woukd be asking for page 1. Im after the deviations that he has found on his EICR.

Ok but a deviation is a design decision made that doesn't comply with the regs but provides an equivalent level of safety to that which would comply.
If they were listed on the eicr, it would only be a comment referencing the eic. If a non compliance was found it would be given a classification code depending on what kind of danger it posed.

 

[naylorpd]

I think this time round I'll be there when it's done. Sounds like I need to be!

S'funny, 20-30 years ago when you hired an expert you just left them to get on with it, nowadays you need to have a much higher degree of understanding to even define the job that needs to be done. But that's getting a bit philosophical...

This is for my house in UK, but where I (mainly) live in Azerbaijan all tradesmen are called "meister" - but most of the time I know more about how to do the job than they do.

 

[Silly Sausage]

S'funny, 20-30 years ago when you hired an expert you just left them to get on with it,

Sadly true.
Read these forums and you'll find that there is a lot of discontent within the industry!

 

[naylorpd]

Maybe they have TNC installations in Azerbaijan?

This is my house in Reading!

In Azerbaijan many, even most, houses are wired without earth cables at all. I have a 3 phase supply with 4x16mm aluminium cores. I put two large earth rods in the garden. The house is wired with T&E and CU imported from the UK, apart from first fix I did most of it myself, including learning to strip 4x35mm SWA.

But over in the thread where you post photos of bad installations I added some pics of the usual standards here.