IT Equipment & Other Sensitive Equipment

stules2905 · Feb 2, 2015

Fairly new to PAT Testing. Been qualified for a while but not done any!

Been asked to carry out all the PAT testing in the office of our company.

Fairly mythed as to the testing of IT equipment and sensitive stuff such as monitors, printers, fax machines and the like.

I am using a Fluke 6200. It does not have an option to decrease the IR voltage and was wondering whether to leave it and just do the 200mA bond.

Got some monitors to test and didn't know whether they were susceptible to damage? Not only ones with IEC leads but also ones with DC Power straight from the plug.

Also like I said, fax machines, boosters, printers, franking machines. If anyone can shed any light on this it would be great!!

Cheers

Stu

Marvo · Feb 2, 2015

I can't help thinking PAT testing IT equipment that's classII beyond a visual check is likely to cause more heartache than it's worth. Even if you connect the L+N together an test using 250v range, the day you come across a piece of equipment with an earth referenced comms system you're still probably going to blow the comms card with a N-E voltage of anything over 30v or so.

Sintra · Feb 2, 2015

If you check your tester you will find that it shorts out the L & N pins and conducts the test to earth. Therefore it doesn't damage anything.

telectrix · Feb 2, 2015

Plug-in PSUs can only be inspected visually. the IT equipment they feed is selv, so there again, visual. afaik, PAT teaters do the IR by linking L-N and testing to E, so should not damage the equipment. and the earth bond test should be carried out using the 100mA setting.

Simlec · Feb 2, 2015

Everything you need to know is in "Code of practice for in-service inspection & testing of electrical equipment"
4th edition

Marvo · Feb 2, 2015

RS232 comms with internal earth referencing possibly won't survive an IR test to earth even with the L+N shorted during the test.

stules2905 · Feb 2, 2015

Simlec said:
Everything you need to know is in "Code of practice for in-service inspection & testing of electrical equipment"
4th edition

Yes but its very contradictory and vague. Just like the 17th Edition.

Simlec · Feb 2, 2015

stules2905 said:
Yes but its very contradictory and vague. Just like the 17th Edition.

Which part/page are you having trouble with?
As far as IET comics go this ones very easy to follow.

stules2905 · Feb 5, 2015

At 500vDC? Could you test monitors and PC's at that?

stules2905 · Feb 5, 2015

Sintra said:
If you check your tester you will find that it shorts out the L & N pins and conducts the test to earth. Therefore it doesn't damage anything.

So you could test all of the things I've mentioned above with a 500vDC IR test as long as the bond was done at a low current??

stules2905 · Feb 5, 2015

Marvo said:
RS232 comms with internal earth referencing possibly won't survive an IR test to earth even with the L+N shorted during the test.

Everybody seems to be contradicting each other with this. Its a nightmare!

stules2905 · Feb 5, 2015

Also. What might be the reason for a high reading on a low current earth bond test to a monitor?

Marvo · Feb 5, 2015

stules2905 said:
Everybody seems to be contradicting each other with this. Its a nightmare!

My statement was from a comms point of view, earth referenced comms cards are very sensitive to N-E voltages. I'm in Africa so I'm not familiar with what your guidelines or regs say but if you're insured and they say it's fine to indiscriminately test networked electronic devices at 250v then I suppose go for it. Personally I wouldn't be so keen on doing this.

stules2905 said:
Also. What might be the reason for a high reading on a low current earth bond test to a monitor?

Is it a classII insulated device perhaps?

stules2905 · Feb 8, 2015

Marvo said:
My statement was from a comms point of view, earth referenced comms cards are very sensitive to N-E voltages. I'm in Africa so I'm not familiar with what your guidelines or regs say but if you're insured and they say it's fine to indiscriminately test networked electronic devices at 250v then I suppose go for it. Personally I wouldn't be so keen on doing this.

Is it a classII insulated device perhaps?

As mentioned before, the tester I'm using doesn't have the function to go to 250v IR. Only 500 DC.

As for the monitor, i can't see anything stating that its class 2. The reading is not non existent. Just too high to pass the test. Testing for the earth on the VGA input.

tazz · Feb 8, 2015

I worked with one of the first manufactures of PAT equipment in 1988, Seaward...in these day pat testing was explained as it should be class 1 and 2, with level results being recorded and checked.
Class 1 would be insulation , earth leakage, load, and bonding, with possible flash......class 2 would only be insulation, earth leakage and load.......there is no possible way of damaging a computer or it device by testing class 2....butit makes great marketing to sell such equipment