Help with insulation resistance testing on a lighting circuit

[soar]

Lost as well ???

Where did the ZE reading come from ???

sorry,from a test before,but i was wrong

 

[Electricalserv]

Don't worry mate that's what the forums for. Good luck

 

[Deleted member 9648]

Have you a copy of the IEE guidance note on testing and inspection?......if you havent it's a gold mine of info and well worth getting.

 

[Deleted member 9648]

Guidance Note 3: Inspection and Testing Guidance Notes for Bs 7671: Amazon.co.uk: Jon Elliot: Books

 

[soar]

Dont take this the wrong way,I'm not having a go....but one of the fundamental requirements of testing is a basic understanding of the principles which you clearly dont have. Can I suggest you do some serious schooling before carrying out any more testing?....Or something is going to go horribly wrong and you may end up responsible.....Friendly advise intended,nothing else.

Sorry anybody can make mistake,,,, and the reason for that is because my R1+R2 reading was 3.67ohms
i thought that was one am asking about,didn't have my form in front of me,,,,,,,,,,

 

[spamwize2]

yes some sense at last

 

[BillyTheSparks]

i forget there was a point in the loft and i did not remove the lamp

I've had TV amlifiers in the loft before connected into the lighting circuit. I always check before testing now. Also could there be any dimmers on the circuit which you missed? Or even an RCD FCU for say an Aqualisa pumped shower in the loft? (Seen this before aswell)

 

[nikmet]

Or sometimes a boiler on the lighting circuit, can spell disaster if you IR test its pcb :-O

 

[BillyTheSparks]

Or sometimes a boiler on the lighting circuit, can spell disaster if you IR test its pcb :-O

Would testing at 250v stop anyting nasty happening in this case??

 

[nikmet]

Would testing at 250v stop anyting nasty happening in this case??

I think it probably would but cant 100% be sure with some sensitive electronic components, and of course that depends whether your aware a boiler (for example) is connected before you carry out the 500v dc IR test as required.

 

[Amp David]

i forget there was a point in the loft and i did not remove the lamp

A lamp left in isn't going to give you low L-E ins res any way

 

[soar]

I've had TV amlifiers in the loft before connected into the lighting circuit. I always check before testing now. Also could there be any dimmers on the circuit which you missed? Or even an RCD FCU for say an Aqualisa pumped shower in the loft? (Seen this before aswell)

no,, only one light

 

[BillyTheSparks]

A lamp left in isn't going to give you low L-E ins res any way

Ah,
Good point.....

Forgot about that. haha

 

[Goody]

Would testing at 250v stop anyting nasty happening in this case??

I managed to blow up a transformer for the shower spotlight whilst doing IR testing with 250 volt setting.

Or was it a coincidence that the shower spotlight stopped working after I did that IR testing?

 

[mozzo]

bit late to this party but L-E IR test should not be impacted by a bulb present. L-N will impact if a bulb is present and the reading will be low.
If you cannot isolate everything and there are sensitive equipment then connect L-N together and just do IR across E and L-N connected together. If the reading is above 1m then ok but if low further investigation is required.