PAT Testing IT Equipment

NeilC · May 27, 2012

Hi,

I have a Metrel BetaPAT Plus MI 3304 Tester and whilst at a loose end, I browsed the autotest codes in the manual. Big mistake! I am now doubting myself in terms of testing IT appliances correctly and would appreciate your views on this please.

I thought an Earth Bond (200mA), Insulation (1Mohm, 250v, 3s) and leakage (3.5mA) was correct? (complies to EN 60950).

When reading other testers comments, they do not appear to power the PC up i.e. run the leakage test?

According to the Metrel Autotest codes the EN 60950 test is - Visual, Earth Bond (200mA), Insulation (1Mohm, 250v, 3s) and SUB leakage ((3.5mA) which will not power the appliance up of course).

What tests do you do on a tower PC, for example?

Thank you in advance
Neil

telectrix · May 27, 2012

What tests do you do on a tower PC, for example?

i gehnerally give 'e m a kick. if they don't fall over .... PASS.

Lighthouse Phil · May 27, 2012

I normally wouldn't do an IR test on any electronic equipment, only on the power cables which supply them. On my Seaward tester, the setting is for "IT equipment -- NI " the NI meaning "No Insulation Resistance Test"
And as telectrix has said, if it dont fall over after a good kick, it passes.lol

Adam W · May 27, 2012

I wouldn't have a problem doing an IR test, especially at 250v.
I'd probably do a polarity test on the lead as well; maybe even test it separately.

NeilC · May 28, 2012

Well..

Thank you for your feedback but that's confused me even more now

mg_smile:

Some say 'don't do it' others say 'It's OK'.

No one has said they run the load test though i.e. power up to test current draw.

I think a kick is probably the most sure way !

Silly Sausage · May 28, 2012

NeilC said:
Well..

Thank you for your feedback but that's confused me even more now mg_smile:

Some say 'don't do it' others say 'It's OK'.

No one has said they run the load test though i.e. power up to test current draw.

I think a kick is probably the most sure way !

Just slap a 'PASS' sticker on them.
Of the countless 100s bits of IT gear I've ever tested, not one has failed.

:wink_smile:

Hence that review that's been published recently, in the last 'Wiring Matters'?

Adam W · May 28, 2012

Ah. Trick question.
A tower PC isn't designed to be moved during normal operation therefore isn't 'portable' so a 'Portable Appliance Test' doesn't need to be done.
Laptop power supplies are generally class 2 with sealed plugs so you only need to do a visual on those.

Taking that attitude should reduce your workload somewhat.

NeilC · May 28, 2012

Adam,

I am assuming you are joking?

A Microwave Oven, a desk PC or even a TV is not designed to be moved during normal operation so would these fall outside the scope of Portable Appliance Testing as well?

I termed the PC as a 'Tower' merely because it was an upright model.

Thanks for your input though - much appreciated.

Adam W · May 28, 2012

You assume correctly. There are however a lot of people doing (or pretending to do) In Service Inspection & Testing of Electrical Equipment who will come up with all sorts of excuses for not testing anything which is likely to take too long, such as calling it Portable appliance testing and arguing about the portability of anything they don't want to test.

As you mention you can't really do a load test on a computer, but being a class 1 appliance you can test earth continuity (soft test) and IR at 250v. Since the lead can be detached you could test that separately, including a polarity test in the same way you would test an extension lead.