Insulation resistance testing

[Bradley6969]

Hi have AM2 next week and just need some help, 3 phase TP+N board, two way and intermediate lighting circuit with 3 switches obviously and one light, doing a global IR test, the lighting circuit say is on L1, so I’m testing all other circuits at once too do I have to switch my switches for every one of these tests
L1-L2,L1-L3,L2-L3,
L1-N,L2-N,L3-N,
L1-E,L2-E,L3-E, N-E

 

[Bradley6969]

If you follow the switching options on my indication of live conductors diagram then you can see which conductors become live and are therefore part of the IR test at the supply when you operate switches.
I have just looked through them and operating each switch once will cover all cores no matter the wiring method, so perhaps this should be the default approach, though it does mean a lot more tests than I would like to perform. Eight tests as opposed to four or six. However it would ensure accuracy.

3 phase board, lighting circuit on single pole mcb let’s say L1, T+E to first switch 3 core to next switch and 3 core to last with T+E to ceiling rose on last switch, so I will only have to switch the lights when doing the global test on L1-E and L1-N as only T+E feeding switch

 

[Richard Burns]

Sounds like you are about there.
So you have this wiring arrangement

I would say this statement "so I will only have to switch the lights when doing the global test on L1-E and L1-N " is correct, however I am not quite sure why you have added "as only T&E feeding switch".
Possibly because the cables between the switches and to the light are not close to the other phases.

 

[Bradley6969]

Sounds like you are about there.
So you have this wiring arrangement
View attachment 38838
I would say this statement "so I will only have to switch the lights when doing the global test on L1-E and L1-N " is correct, however I am not quite sure why you have added "as only T&E feeding switch".
Possibly because the cables between the switches and to the light are not close to the other phases.

Yes what I meant was there’s only one phase to lights so will only need to switch when either L1-N or L1-E

 

[Richard Burns]

Correct.
(Not available from now on today)

 

[Risteard]

Yes what I meant was there’s only one phase to lights so will only need to switch when either L1-N or L1-E

And L1 to both L2 and L3.

 

[Bradley6969]

And L1 to both L2 and L3.

How come

 

[Gavin John Hyde]

so glad i'm getting outof it after 50 yeaqrs. back in the day, it was wire it, connect it....if it went bang, then tester came out.

For a lot of fly by night electricians it has not much changed.... they turn it on and if it goes bang they run off to the next job,

 

[Risteard]

How come

In case the insulation breakdown is between phases.

 

[Bradley6969]

In case the insulation breakdown is between phases.

Didn’t have to do that lights was on L1 so I flicked switches between L1-E L1-N and passed

 

[Risteard]

Didn’t have to do that lights was on L1 so I flicked switches between L1-E L1-N and passed

The lights might be on L1 but the insulation breakdown on the strappers that you are testing for could be to another phase.

 

[Bradley6969]

The lights might be on L1 but the insulation breakdown on the strappers that you are testing for could be to another phase.

Fair enough i see both points if your on site and cant visually see but on the AM2 you can see and you wired it

 

[Risteard]

Fair enough i see both points if your on site and cant visually see but on the AM2 you can see and you wired it

Is it not singles in containment?

 

[Simonslimline]

Is it not singles in containment?

The lighting circuit is wired in 6242Y and 6243Y in the AM2.

The RFC is wired in 6491x. its all in the same containment though.

 

[Bradley6969]

Is it not singles in containment?

Yes that’s it

 

[Bradley6969]

Is it not singles in containment?

No sorry lights are wired in T+E and 3 core +E