Insulation testing problems

[dunscombe]

Hi all, if I’m getting an insulation reading of 0.03 across N & L on a lighting circuit what would cause this? Neutral earth, live earth, are in the acceptable realms.

 

[westward10]

I assume there is something connected across line and neutral.

 

[davesparks]

It's either going to be a load you've haven't disconnected for the test or else there's a fault.

 

[dunscombe]

I assume there is something connected across line and neutral.

Would that also double with the fact that I’m getting a 99.9ohms reading on resistance testing??

 

[westward10]

Would that also double with the fact that I’m getting a 99.9ohms reading on resistance testing??

A resistance test across line and neutral?

 

[davesparks]

Would that also double with the fact that I’m getting a 99.9ohms reading on resistance testing??

Is that a reading of 99.9ohms or is that just the maximum value your meter can display?

 

[dunscombe]

A resistance test across line and neutral?

Yes mate

 

[Rockingit]

Well for practical purposes that's a dead short so you've got a dead short or a lighting fixture still in place. Could also be a neon indicator if you've lights on a neon switch such as outdoors - or a PIR sensor as well.

 

[dunscombe]

Well for practical purposes that's a dead short so you've got a dead short or a lighting fixture still in place. Could also be a neon indicator if you've lights on a neon switch such as outdoors - or a PIR sensor as well.

Ok I’ll look into it!

 

[dunscombe]

Well for practical purposes that's a dead short so you've got a dead short or a lighting fixture still in place. Could also be a neon indicator if you've lights on a neon switch such as outdoors - or a PIR sensor as well.

Is it sufficient just to turn the neon FSU off and test? Found one in the loft

 

[Rockingit]

Is it sufficient just to turn the neon FSU off and test? Found one in the loft

Just lift it out of circuit altogether

 

[westward10]

For what reason are you testing this circuit?

 

[buzzlightyear]

it was not long ago that some member put on here about IR testing what you should be looking at if low insulation testing .