Low Resistance on IR Testing

[wcavanagh]

As you would expect I get >999

Not looking good and the whole house is wired up with this

 

[DetlefSchmitz]

Not great - for the record, did you change the batteries?

 

[wcavanagh]

I sure did just on the chance. More hoping etc. What a nightmare, almost impossible to pull all that cable out now.

Think I need a drink

 

[Jackrae]

What do you get when you test at 500v (I see you were testing at 250)
What manufacturer name on the cable -- if none then 'nuf said

 

[wcavanagh]

I will try at 500 just now,

The cable is https://www.tlc-direct.co.uk/Produc...MI3LbtjMG54AIVA7DtCh05QAjLEAQYASABEgInUvD_BwE

CE marked and Basec cert

 

[wcavanagh]

12.7 when testing at 500v

 

[Harry Bloomfield]

From a brief read of this thread, I would suggest the issue is just one of moisture trapped behind the accessories - the switches and sockets etc.. Try undoing the fixing screws and dropping them forwards, clear of their boxes, to allow the damp to evaporate.

 

[JohnW2]

From a brief read of this thread, I would suggest the issue is just one of moisture trapped behind the accessories - the switches and sockets etc.. Try undoing the fixing screws and dropping them forwards, clear of their boxes, to allow the damp to evaporate.

That theory has been discussed - but how could it explain the low IR readings when an unused reel of cable was tested?

Kind Regards, John

 

[wcavanagh]

The problem is i tested a reel that was left over and that is still pulling in a low reading.

 

[Harry Bloomfield]

but how could it explain the low IR readings when an unused reel of cable was tested?

Sorry, I said I had skimmed through. It would not explain it - I would guess the Meggar has issues, rather than the cable then. Have you established the Meggar is showing infinity with nothing connected?

 

[wcavanagh]

I sure have, >999 when tested

 

[Harry Bloomfield]

The problem is i tested a reel that was left over and that is still pulling in a low reading.

In 50 years in the industry, I never came across new PVC cable which was low IR. Pyro and paper, yes, but never PVC.

 

[333rocky333]

Zap the part coil or an isolated section on 1000volt preferably in the dark, sometimes you see the cable tracking across

 

[wcavanagh]

In 50 years in the industry, I never came across new PVC cable which was low IR. Pyro and paper, yes, but never PVC.

Not what I want to hear, nightmare. Strange how all reels have produced same result, im stuck with what to do now.

 

[Harry Bloomfield]

Not what I want to hear, nightmare. Strange how all reels have produced same result, im stuck with what to do now.

I was suggesting it is very unlikely the cable is faulty - does the Meggar show infinity when tested with nothing connected?

The other possibility is nails and screws through cables, but usually they will produce very low Ohms and unlikely whoever managed to hit every circuit anyway.