Low insulation resistance and tripping circuit breaker

[shug1693]

I've just done an insulation resistance test between line and earth and got 0.0 Mohms for most circuits. Obviously this is an F1, but what I don't understand is why the CB doesn't trip. Is the answer that the resolution on my tester isn't high enough? So I could for example have 0.049Mohms and this resistance is high enough to prevent a significant earth fault loop path?
Thanks for any thoughts...

 

[westward10]

Yes you do when you are testing that individual circuit/cable so you’ve never disconnected an Earth when fault finding??

Cpcs are not disconnected to carry out an IR test.

 

[Grant1987]

You do not disconnect the cpcs for an IR test.

When you have multip

Cpcs are not disconnected to carry out an IR test.

I didn’t say that I wudn disconnect earths on doing normal IR test. the guy posting has multiple faults by swnd of it and is testing across the common earth and neutral bar as far as I’m aware? In that situation I disconnect the neutrals out and test and then find the circuit which is at fault. Once that’s established I will take the Earth out aswell and test individually for that cable to be definitive
[automerge]1600975081[/automerge]

Cpcs are not disconnected to carry out an IR test.

You don’t need to try lecturing me on fault finding I’ve carried out in the hundreds of fault finding especially within the area I live with old mining community with terraced housing full of damp Old accessories etc. . you won’t believe a lot of the faults I’ve found and learnt from over the years

 

[westward10]

I don't believe I am lecturing anyone.

 

[Grant1987]

I don't believe I am lecturing anyone.

Ok well just thought you was telling me I was wrong

 

[GBDamo]

Did you unplug/disconnect any devices?

Hidden spurs with flaming neons, the devils own work.

 

[Grant1987]

Hidden spurs with flaming neons, the devils own work.

Agreed, and those extension leads with flaming neons