250v Insulation Resistance test - Lots of D/lights

[chrisgc]

I know when a 250v insulation resistance test can and cant be done.

But when it says that a 250v is ok when its impractical - what is the definition of impractical?

Ie for this scenario:

How many downlights would be deemed as impractical to remove (as they are buggers sometimes to remove especially when there is for instance 20 plus downlights) for it to be ok to only do a 250v IR test?

Please also bear in mind that the reason would have to stand up against an assessor for assessment - as dont want it to appear as just being lazy.

 

[Guest111]

Imo 20 downlights would be classed as lazy not impractical to remove but thats just my opinion.also depends on who wired it if its me and I know its right thats one thing,if its someone else and my name was going on the ticket thats another.

 

[trev]

Why not IR them before lamping up?

 

[Guest111]

Why not IR them before lamping up?

Spoilsport,I was waiting to see if he,d spot the obvious answer! lol

 

[trev]

Sorry Phil
Great minds eh? or is it the other one

 

[telectrix]

if it's an nexisting installtion,the link L/N and test to E @ 500v. if it's new, as said befoere, IR test before fitting lamps.

 

[Guest111]

Well thats the top 3 answer out of the way,getting a bit like family fortunes this one.

 

[chrisgc]

It was more just a consensus question as in whats classes as impractical. And on existing installation.

I know its best to do at 500v but but if there is a few lighting circuits and for example 20 dlights on each circuit thats then 60 lights which need removing, and these lights spring toggles are like mouse traps when putting them back.

So it was just a question as regards to practability.

 

[trev]

I suppose it would come back to how much time you have available to get it done, eg if it's 9:30 am and you have all day then delamp them and do it l/n/e @ 500v DC. If it's 16:45 then it's down to you to decide.
Personally, I'd much rather delamp. Well, get the apprentice/mate to

 

[GaryM]

if it's an existing installation,the link L/N and test to E @ 500v. if it's new, as said before, IR test before fitting lamps.

Spot-on.

 

[SirKit Breaker]

if it's an nexisting installtion,the link L/N and test to E @ 500v. if it's new, as said befoere, IR test before fitting lamps.

As tel says, and if you are unsure, or intend getting involved with test and inspection, put the IET guidance note 3 on top of your to buy list.

Cheers.........Howard

 

[londonlec]

Are we talking eicr here?

 

[chrisgc]

Another reason I ask about removal of quite a number of downlights is that they can and do pull out edging of the recess on the plasterboard due to tight fitting.

And if ceiling has been recently painted this is obviously not decor friendly - so was wondering if this would also be classed as practical to remove for an IR test at 500v or do just the 250v IR test?

 

[sythai]

Another reason I ask about removal of quite a number of downlights is that they can and do pull out edging of the recess on the plasterboard due to tight fitting.

Any reason why you would need to pull the lights right out just to de lamp ?

Maybe I've missed something....

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