Testing Question

[wired]

Hi I'm still training to be a sparky - so be gentle with me!

Does anyone know why on a Schedule of Test Results Form it asks for IR results between Live/Live and Live/ Earth but on a Minor Works Certificate it asks for all 3 results i.e. Phase/Neutral, Phase/Earth, Neutral/Earth? Just curious.

Also, in the REAL WORLD if you were testing a complete existing installation for IR would you go around the house disconnecting anything that would effect or be damaged by the test i.e Indicator lamps & Dimmer switches or would you just test between Phase & Neutral connected together and Earth? Is doing it this way frowned upon unless you have no option?

 

[JohnD]

if yu do an IR test with stuff connected then (1) you might damage it (2) there might be poor IR on one of the appliances.

 

[Chivers7]

if yu do an IR test with stuff connected then (1) you might damage it

and if you did who do you think would have to foot the bill?? so always best to disconnect stuff remove bulbs etc.

 

[CallEdsFirst]

You could leave stuff connected but leave quickly in case the homeowner tests your IR.

 

[wired]

Thanks. So are you saying that even if you test between Phase & Neutral (connected together) and Earth you would still disconnect equipment etc? Or would you always test between Phase/Neutral, Phase/Earth, Neutral/Earth and disconnect eveything.

It's just that the regs (if I've read them correctly!) say that if you can't disconnect equipment then you should test between Phase/Neutral and Earth. So, I just wondered if it's necessary to go round a property disconnecting stuff if the Regs are happy with this "shortcut".

 

[CallEdsFirst]

IF you can't! not if you can't be ars*ed! I imagine if you got inspected and it was determined that it was reasonable to disconnect and you hadnt, just providing the minimum of testing, then there could be trouble. Testing isn't a chore, its so you can check that people are not going to die because of what you have done (or not done!)

 

[wired]

Thanks Calledsfirst. So it's a kind of last resort I suppose. I don't suppose you know the answer to the first part of my Post do you? i.e Why does a Schedule of Test Results form not ask for an IR reading between Phase and Neutral but a Minor Works Cert' does?
Thanks again

 

[RF Lighting]

Where / who have you got that schedule from?

All NICEIC certificates (only ones I use) ask for P/N P/E N/E values, and all the non domestic certs ask for P/P too (if applicable)

 

[davelx]

Page 297 of the Regs, for a start!

 

[wired]

Hi RF Lighting, as Davelx says it's on page 297 of the Regs.

It's a bit misleading (at least to beginners like me!) as it says Live/Live in one column and Live/Earth in the next. We're being taught that Neutral is considered a Live conductor and that we should no-longer use the term LIVE but PHASE instead.

I didn't realise that NICEIC would have their own Certs'. But the question is which one is correct..?

On Page 291 there's an example of a Minor Works Cert' which does ask for all 3 test results, weird!

 

[RF Lighting]

very odd.

I wonder if it is so you can either do a P&N/E test and record the result or a P/E & a L/E (lives to earth (phase(s) and neutral)) and record the lowest (worst) result for live/earth, and P/N or P/P and record the lowest (worst) result for live/live

(you need to test all phases to each other, neutral and earth if it is a TP installation)

Hope that makes sense

 

[wired]

Thanks RF. Yes it does make sense, I hadn't thought of that.

Just one final question to further show my lack of knowledge what's a TP installation?

 

[RF Lighting]

Three phase installation. Sorry another abbreviation!

 

[wired]

Thanks. As soon as I hit the SUBMIT button I realised what it must mean!!

 

[securespark]

I do a method 2. Put the phases together & test to earth. Perfectly acceptable according to the ECA.