Bathroom Light

[Spark123]

Not likely the MCB, is more probably something they have plugged in / fixed equipment?
You also don't say where your test is from, L-N?

 

[Tonyx]

Only things plugged in are fridge and washing machine which was the same situation before energising the board. Yes test was from L-N

 

[Spark123]

You are bound to see a L-N resistance with items plugged in, the resistance of the devices is probably less than a few ohms in total. You are measuring Millions of Ohms with an IR tester!
Unplug everything before carrying out IR testing.

 

[Tonyx]

Ok thanks I'll unplug them and test again.....cheers

 

[Spark123]

You might also find out the expensive way that items with semiconductors in them don't like to be IR tested too!

 

[Tonyx]

I know the fridge is still working but haven't tried the washing machine

 

[flameport]

It's the fridge.

The first time it was probably cold, so was effectively switched 'off' via the thermostat.
The second time it had been off for a while, so the fridge had warmed up and the thermostat operated. You were measuring across the motor, which would show up as a very low resistance.

 

[Tonyx]

Excellent makes sense.......many thanks. Off to try it now, fingers crossed

 

[Tonyx]

It was the fridge......thanks very much to both of you for your help, much appreciated

I note also that rcbos dont like 500v, even with the aux tails out

cheers,

Tonyx

 

[Spark123]

Yep - they contain semiconductors!

 

[securespark]

Insulation resistance test was fine.....????

The reading?

Sorry, Ignore that! I posted it without reading page 2...