PAT Testing Method ?????

[Dizzy_Maskell]

Guys just for your thoughts,

I was on a site recently and we encountered the local PAT guy, luckily we as a company don't do PAT so I have limited knowledge on the subject.

He was using an extension lead and testing about 10-15 items in one go and then stickering them all up after testing all the items in one hit.

We asked him out of curiosity if you can do this as we where not sure and he advised it is the equivalent of a global test when doing IR testing. He told us that if all 15 etc pass in one go then individually they must pass so of course it is ok.

Just looking for people's opinions on this as I have limited PAT knowledge has anyone else seen this done ????

 

[Paultrim123321]

What do you think? How has he carried out Earth Bond tests? Leakage accumulation? Are they all the same class or some Class 1 & 2?

Why are you worried? It's not you is it who is carrying out the tests?

Did he come on horse back and carry a lasso?

 

[RyanCheetham]

I can see the reasoning behind it makes sense but does sound a bit like a cowboy move. I also do not do pat testing so cannot comment on the effectiveness of this method. I would do it one by one if purely for more accurate results

 

[Dizzy_Maskell]

Well he was wearing a Stetson and like I said we did question him but told us he was allowed to do it,
I was more concerned he said its like doing global tests meaning this guy obviously attempts fixed wiring tests

 

[Dizzy_Maskell]

Yeah sorry guys they where all the same item e.g. 15 kettles then 15 hair dryers etc

 

[Darkwood]

Many tests are required to ensure an item passes although global testing would indeed pass multiple items at once this is only on the insulation test, this cannot be done when measuring earth path resistance or flash testing, if he is just insulation testing and then passing them he isn't doing the full range of tests required, my test unit performs several tests per item (actual tests performed dependent on what is been tetsted)...

Because you have to perform multiple test per item there is no gain from global testing IMHO and this doesn't sound right at all, are you been issued with a official results cert that covers every item with the corresponding recorded values?

Ask him to provide a copy of his City and Guilds 2377 qualification for your insurance company and watch him sweat!

 

[Dizzy_Maskell]

Well we only contract there so not really our problem but we looked at his results page and its a word document that just says item number then all usual test options with the word pass copy and pasted all the way down the list, home made certs copy and pasted always concerning

 

[Dizzy_Maskell]

We did not know whether or not to make a comment to the maintenance manager

 

[RyanCheetham]

I think you should share your concerns with the client. Worst case is you are missing information and he is doing it correctly and you look a bit of a fool. But maybe he is being dangerous and putting lives at risk. Duty of care means you should advise of your concerns just in case

 

[Darkwood]

A behind closed doors comment would be nice ... explain your concerns then just ask to to ask for results sheets with test results and measured readings and his C&G 2377 for the insurance company.

To note! you don't have to have a CG2377 you just have to be competent to do so but from what you say it seems he's taking shortcuts and asking for it may be the best way to expose this.

 

[Dizzy_Maskell]

Thanks guys ill inform the client

 

[RWJ]

I was going to say cowboy......

but.....

When we do the theatres and hire companies they tend to have rack cases with radio mic receivers all powered by small 9v plug in psu's that are all then plugged in to a 4 / 6 way extension. We tend to just test the plug on the extension, as the psu cable's are all nicely tie wrapped and dressed. I think they buy whole unit like this as they all appear to be the same wherever we go.

 

[oldtimer]

Sorry its not a neat idea its just not legal in my view when I do a test on say a kettle I get the earth test then the IR and I log both he could only test one of the kettles so he has not done the test correctly and the same goes for Class II I think if you quiz him he will not be an electrician and as previously stated ask him for each of the kettles earth test result me thinks he has tested one and put this reading down for the rest.

Just to add this is the very thin that puts PAT in a bad light but such is the pressure to get 300 items done a day this type of thing turns up maybe I will ask the guy on the likeden forum

 

[Lucien Nunes]

Deleted

 

[Lucien Nunes]

rack cases with radio mic receivers all powered by small 9v plug in psu's that are all then plugged in to a 4 / 6 way extension

However normally all those little wall warts are Class 2 and a global test pass is sufficient as you're only doing IR and leakage. When doing Class 1 audio racks you need to split things up anyway so that only one piece of kit is having its earth tested at a time. I often build equipment racks with quite a number of larger switched-mode PSUs and the total leakage current is sometimes borderline. I have to split them up to prove that no one unit has excess leakage, but then also record the total for the rack as that is the figure that governs whether it's safe to plug in via a socket outlet. With separate appliances that are not parts of something, I'd be more impressed to see the tester doing separate tests. The more plugs and sockets you have between the tester and the item on test, the more likely the test is to be invalidated by a poor connection etc.

Lucien

 

[Tiny Spark]

Yeah agree this sounds very dodgy to me.
You could argue a global ir test is ok for class 2 appliances but there is absolutely no way you could justify this for class 1 stuff.
You have to be able to provide results for each individual item which he obviously can not as he will just get the worst possible scenario.
Just out of interest was he doing function or leakage tests?

 

[Dizzy_Maskell]

Think one kettle appliance turned on e.g hair dryer then the rest left off, he would have to sometimes he would do about 20 kettles I think the fuse may go if he tried do them all on load.
As I said he only puts pass or fail down on his sheets so it is non specific.
With regards to items he says he did 200 items a day but we never see him after 1PM so I think he must do 5 hours a day at max and still gets 200 items done must be some PAT but as I sat its not my forte so can't shoot him down but I have my suspicion

 

[Risteard]

Yeah agree this sounds very dodgy to me.
You could argue a global ir test is ok for class 2 appliances but there is absolutely no way you could justify this for class 1 stuff.
You have to be able to provide results for each individual item which he obviously can not as he will just get the worst possible scenario.
Just out of interest was he doing function or leakage tests?

Actually I think the justification could only be for Class I - as the cpc connection is there and therefore you will get the insulation resistances in parallel. For Class II it is no good as you would need to test between live conductors and exposed metalwork etc. which clearly would require you to probe each asset.

But as said, even with Class I, then it leaves the problem of needing to conduct an earth bond on each asset - so is there any real benefit? I suspect not.

Another problem is that you would have to verify that the fuses were all intact for the insulation resistance test to be meaningful.

 

[ackbarthestar]

We asked him out of curiosity if you can do this as we where not sure and he advised it is the equivalent of a global test when doing IR testing. He told us that if all 15 etc pass in one go then individually they must pass so of course it is ok.

New terms for the electrical glossary.

1/ Drive-by PIR
2/ Global PAT

I was interviewed for a testing job sometime ago.

"We don't do R1 + R2 on our new builds, Just Ze, Zs on the skts and a global IR"

Why don't people just slow down, do the job properly and take pride in their work

 

[Risteard]

New terms for the electrical glossary.

1/ Drive-by PIR
2/ Global PAT

I was interviewed for a testing job sometime ago.

"We don't do R1 + R2 on our new builds, Just Ze, Zs on the skts and a global IR"

Why don't people just slow down, do the job properly and take pride in their work

In fairness, the global insulation resistance part is the correct way to do that! Although obviously cpc continuity should be verified via dead testing before energising for initial verification!