What cert?

[Stever_777]

Hi, a customer of mine has just bought a house. He has no elctrical history on the property, he says its never been lived in and that it was a show home 3 years ago. the builder has gone bust and cant be located. the supplier would not put the fuse in until an electrician gave him a "safety certificate" in his words. Im a Domestic installer, so i went along and did an inspection and dead tests which uncovered very poor IR readings on half the circuits.

I didnt leave him with a cert. I am going back tmrw to locate the faults.
Since my last visit the supplier has been back to his property and put the fuse in and told my customer that all I must do when probvlems are solvedis connect the tails into the isolator which is in the meter cupboard.

I am quite new to testing and have only just become a DI so MY QUESTION IS, what certificate shall I give him when faults fixed and full set of satisfactory results recorded.

I cant give him a periodic under the DI scheme and cant issue a EIC cause I did not do the design or installation.

Please help?

 

[Octopus]

Why can't you do a PIR, any numpty can - there isn't any check on competance.

IMHO I'd do a PIR and give him a copy confirming the tests have all been done. If you do this make sure you state on the PIR why you are doing it and what it does and doesn't cover.

 

[Des 56]

Download them here
Forms for electrical contractors - IET Electrical

 

[Stever_777]

Download them here
Forms for electrical contractors - IET Electrical

Thanks Des but I`ve got a pad of those green PIR`s that you buy off the shelf at your local wholesaler.

 

[GLENNSPARK]

A periodic inspection report is just that...a report..nothing else..so why would it be notifyable? Work done to correct any faults/non compliance may/would be notifyable though.........

 

[telectrix]

as above. but what readings were you getting for your IR 's. ? some guys panic if readings are below 299 Meg. anything over 2 Meg. is a pass, also, are you measuring L/N with loads connected?

 

[Thomas123]

you said you had low IR readings? if the house has been empty for 3 years, damp could of got into the cables? check for neons, loads, lights in attick, aerial boosters in attick etc

 

[GLENNSPARK]

I had it as 2 Meg tel...if testing the lot at once (at the tails) but 1 Meg for individual circuits.....parrallel paths n all that.........

 

[telectrix]

other way round, i think glenn.

 

[GLENNSPARK]

GN3 P(38) table 2.2 and paragraph 4.
Fire alarm systems...2 Meg minimum....

 

[telectrix]

don't have gn3 to hand, mate, but if you are IR measuring several circuits in parallel, you would expect a lower reading than that for individual circuits.

 

[Deleted member 26818]

The minimum IR allowed is 1MΩ, except for fire alarm circuits where the minimum is 2MΩ.
When conducting any IR test, a reading below 2MΩ, should be investigated, to see whether there are any latent defects, (I assume with fire arlarm circuits anything below 3MΩ or perhaps 4MΩ, will require further investigation).
As such if you conduct a global IR test and obtain a measurement below 2MΩ, you should then test circuits individually, and if any are again below 2MΩ, investigate to ensure there are no latent defects.

 

[GLENNSPARK]

don't have gn3 to hand, mate, but if you are IR measuring several circuits in parallel, you would expect a lower reading than that for individual circuits.

Yep tel But BS7671 refers to "latent defects" As i said parralell resistances will bring the overall value down thus giving bogus readings but I can only go by the table 2.2 given on P (38) for DC test voltages applied to final circuits:
500V = 1.0 MEG
1000V= 1.0 MEG
and
10.3.3 INSULATION RESISTANCE
P(83) OSG
table 10.1

 

[GLENNSPARK]

The minimum IR allwed is 1MΩ, except for fire alarm circuits where the minimum is 2MΩ.
When conducting any IR test, a reading below 2MΩ, should be investigated, to see whether there are any latent defects, (I assume with fire arlarm circuits anything below 3MΩ or perhaps 4MΩ, will require further investigation).
As such if you conduct a global IR test and obtain a measurement below 2MΩ, you should then test circuits individually, and if any are again below 2MΩ, investigate to ensure there are no latent defects.

It could also be used to demonstrate the impending failure of final circuit/s for recommendation for a rewire (or portions of it).....

 

[Deleted member 26818]

It could also be used to demonstrate the impending failure of final circuit/s for recommendation for a rewire (or portions of it).....

I believe that is what is meant by latent defects.
Personally, I'd investigate any measurement below 10MΩ.