Acceptable readings for a NEW installation

[Guest 004]

I don't need to. It was the fact you mentioned there is water between cores which is the joke here.

Oh so maybe you think the cable is pinching then?

 

[spark 68]

You cant fail it... Its 40x greater than the minimum requirement BS7671.. It could be seen as fraud leading a customer into thinking its not passable!

If this cable is part of the DNO supply then it is not subject to BS7671, it will be whatever the DNO decides is acceptable (EDF in this case).

If this is a lot lower than other identical cables/risers then I would be concerned too, did you try wiping the terminations riser etc. with a dry clean rag ? it is more likely the terminations or the switchgear being damp than between cores, and did you test between all of the cores (all 10 tests) ?

 

[bigspark17]

If its part of the DNO then why are you ir testing this cable?

 

[spark 68]

If its part of the DNO then why are you ir testing this cable?

Probably because they will want the dead test results before they will energise it.

 

[Guest 004]

If its part of the DNO then why are you ir testing this cable?

because 'we' installed it for them

- - - Updated - - -

Probably because they will want the dead test results before they will energise it.

absolutely

 

[spark 68]

I think I would have investigated further, maybe as far as testing only the cable by itself (after disconnecting and drying the ends) in case it was damaged.

 

[Guest 004]

I think I would have investigated further, maybe as far as testing only the cable by itself (after disconnecting and drying the ends) in case it was damaged.

Yes would have liked to have tested before it was connected. Will check equipment for any flash test results. Not really practical to disconnect now.

 

[i=p/u]

Just test at 500v too

 

[LeeH]

Yep, 500V for any thing up to 500v if I recall my 2391 days correctly.

 

[Guest 004]

Sorry forgot to mention that was getting readings between phases as well, so would need to test at 1000V

 

[LeeH]

You sure? Please correct me if I'm wrong. 500v test voltage for up to 500 line voltage.

I've been wrong before!

 

[Guest 004]

Reg 612 says you are correct.

If I test at 1000V then readings will go up to 500 meg. Test at 500V then readings will go to 299 meg.

With my meggar anyway.

 

[plugsandsparks]

Did a long run recently in 120sqmm, measured it on the drum, measured it when buried and lastly when terminated, a bit OTT maybe but had >1999 right up until I terminated on to the customers own fuseboard, then it dropped to 1500. If it was as low as 40M , I would have been pretty upset. If you can get at both ends I would have a good look for dirt etc and perhaps un- bolt the lugs so they are in free air and test again.

 

[spark 68]

You sure? Please correct me if I'm wrong. 500v test voltage for up to 500 line voltage.

I've been wrong before!

Only according to BS7671, as this is a DNO cable BS7671 does not apply, I am not sure what the DNO requirements are, but when testing switchgear we used to test at a 1000V (up to Giga ohms) and at 2.5kV for 25 seconds, BS7671 is not the only regs about, don't forget BS7671 is the absolute minimum standard even when that standard does apply