PAT Testing extension leads

[longshanks]

Hi

Just got into PAT testing and have done a few jobs without too much trouble. The tester i use now is the Seaward Primetest 250. I checked some extension cables at home and on one of them i got a strange reading. The extension i tested had the black master socket then 5 others, i know that the black socket has to be used 1st then the others will work.

When i test it i get good reading from the black socket but when i test all the others i get these readings:

Rpe 0.03
Riso 19.99
Ileak cr05 (on other sockets i get OPEN)
Fail

What does this mean and if i tested this at an office or anywhere, would this be a fail?

Many thanks

Tony

 

[topquark]

I take it that this is one of the extensions that power off you other peripheral devices when the main (black?) socket is not drawing any power?

 

[longshanks]

Yep that's the one

 

[topquark]

I don't think you can test the other sockets in isolation. That's possibly why you're getting Ileak of Open (IE zero current flow) as well, there is no guarantee that this is accurate for that lead without a current using load attached, as it is effectively off at the other sockets with no load. So although that's what you expect there is no guarantee that is the case when it's in use.

 

[longshanks]

So when i come across these in future i should test the black socket only and pass it?

 

[topquark]

I wouldn't say that!

I think you would need to simulate that socket (the black one) as being in use (probably at it's maximum current rating) and then leak test the others IMHO. I'm sure someone that does regular PAT testing may be able to give a better answer.

I suspect that these type of devices have not been considered properly yet. I would try contacting IEEE, IET or another advisory body.

 

[longshanks]

Many thanks for you info

 

[72-van]

I have never came across one of these on my travels but i can tell you what i would do given these circumstances
..contact the manufacturer /supplier
i bet its info of some kinda id somewhere on it .I have had to call manufacturers a couple of time re similar situations .
BUT
If i could not 100% be certain that its ok then i would FAIL the item and give a qualified reason for doing so in my summary which i provide with the downloaded test results .
eg unable to test the appliance to ascertain ....
unable to contact the manufacturer to get advise on testing this unusual item.
They can choose to dis-regard this at there own peril.
After all you are not there to pass everything but to give an informed judgement as to whether these appliances are fit in your opinion to remain in service.
One last point i have on occasion found appliances that give weird readings only to find that on the appliance there is a wee sticker telling you that when testing these appliances such and such should be done and the results should be ..
I had this on some medical autoclaves.

72-van