IR testing on CU upgrade

[n180]

On an eicr we can write LIM for L-N testing and do a test with L-N connected to earth if there's too many electronics to unplug.

What about on an EIC when only doing something like a CU upgrade? Can't do the IR test between L-N with too many things to unplug and we can't write LIM on EIC in the live-live column?

So what to write in the L-L test columns on an EIC?

I know its always good to do the EICR before upgrade, but still got to do the EIC afterwards.

Thanks in advance.

 

[Deleted member 72666]

L&N to earth is not a problem, but i've always been taught that goes only in the L-E column.

Is that reading also accepted in the L-L column?

Not if you haven't tested L-L.

 

[Risteard]

Or better still N/V.

N/V is not a recognised entry on an EIC.

 

[Deleted member 26818]

As far as I’m aware, there’s no British Standard for filling out a Schedule of Test Results.
I would not record calculated results, because the schedule is for recording the results of tests.
I would not use X, as it might be taken as meaning fail.
I would not use / as it may be taken as a tick.
I could use \ though I prefer to use -.
N/A is pretty universal as being taken for Not Applicable.
N/V might need some explanation, but then you might have to explain why the measured value for Zs is below the Maximum allowed, yet it still fails.

Both the OSG and GN3 have examples of filled out Certificates and Reports.
Not sure whether they are examples of how to, or how not to fill them out.

 

[Risteard]

Given that the Schedule of Test Results derives from BS 7671 then the stipulations therein should be adhered to. For an Electrical Installation Certificate this means that everything is either compliant or inapplicable.

 

[Deleted member 26818]

Inapplicable could apply to all of the test results for out going circuits when conducting a CU change.

 

[Risteard]

Inapplicable could apply to all of the test results for out going circuits when conducting a CU change.

Not all of them as you need to verify that you've correctly reconnected them and that ADS will operate. Certainly some of it may not be applicable though.

 

[TJ Anderson]

Inapplicable could apply to all of the test results for out going circuits when conducting a CU change.

As above. Circuit protection is often altered in these upgrades. (3036 to 60898 OCPD's for example) so to confirm ADS, Zs would have to be taken and recorded as a minimum. Additional protection by RCD may well have been added too and these would also need testing and recording to prove satisfactory.

 

[Dave OCD]

I always test each circuit individually and record all Insulation Resistance and Zs values when doing a CU change,as well as the RCD/RCBO operating times,Ze and PSC etc, surely that's the right way to prove the circuits are safe for reconnection ?

 

[TJ Anderson]

I always test each circuit individually and record all Insulation Resistance and Zs values when doing a CU change,as well as the RCD/RCBO operating times,Ze and PSC etc, surely that's the right way to prove the circuits are safe for reconnection ?

Yes mate, me too, that's doing a thorough job.

 

[Baddegg]

Me as well Dave, takes me longer but I sleep better....

 

[Deleted member 26818]

As above. Circuit protection is often altered in these upgrades. (3036 to 60898 OCPD's for example) so to confirm ADS, Zs would have to be taken and recorded as a minimum. Additional protection by RCD may well have been added too and these would also need testing and recording to prove satisfactory.

If you’re changing from BS 6036 to BS EN 60898, then you should be checking Zs beforehand, especially now we have Cmin.
Yes, if you’ve installed RCDs, they will need testing, because it’s part of the work you have done.