PAT testing network switches

[Shiny_Guru]

Does anyone here know of any firm guidence about the PAT testing of network switches installed in cabinets?

 

I have opposing views being expressed around the school, some say yes, because if you take out the 4 face plate screws you can continue to use the equipment in a portable manner (like on my test bench) some say no because with those screws in it becomes 'fixed' equipment and thus exempt.

 

Sadly our schools pat testers have just turned off our entire science block after pat testing the cabinet - having refused the keys when offered they took the mains lead that went into the cabinet and then failed the unit because the earth connection was not up to scratch. Grrrrrrrrr :x

 

Any guidence gratefully recieved

[webman]

All of ours are tested by the LEA PAT testing team.

[petectid]

I have opposing views being expressed around the school, some say yes, because if you take out the 4 face plate screws you can continue to use the equipment in a portable manner (like on my test bench) some say no because with those screws in it becomes 'fixed' equipment and thus exempt.

 

Ours have just been tested here, I always thought it was the way the appliance was attached to the mains that determines whether it is tested or not. A dishwasher with a plug top is tested put if it was powered through a fused connection unit it would not be tested. Because most switches are plugged into sockets using a power lead that can be disconnected at the socket and the appliance then there are two tests one for the lead and one for the switch.

[SteveT]

PAT = PORTABLE Appliance Testing !!!!!

 

I`ve got the piece of paper (cuz I`ve done the "course" !! :? )

 

Any piece of electrical equipment which is likely to be damaged by pushing an unregulated current through it should NOT be tested by using a PAT machine!!! Furthermore, Network Switches are not portable so do NOT require testing. It is suggested that such equipment is given a regular visual check and a record kept of such checks. I check ours formally once a year, but obviously informally everytime I am in the relevant cabinet.

 

You can download a really useful PDF from the HSE about this. It is called "Maintaining portable electrical equipment in offices and other low-risk environments." HSE considers schools to be low-risk environments. (Yes I know that may seem ridiculous, but is actually based on accident statistics and research) It is the first download here:

 

Linky

 

The key thing is that you do not have to be a fully qualified electrician to carry out these tests, but I would strongly suggest you do the course. It`s a very simple one day affair. I did mine with First Stop Safety

who run courses all over the country. It didn`t cost very much (about £100 ) and was actually quite thorough.

 

We had previously been paying a contractor over a thousand pounds each year to do this when it only takes me a couple of days during the summer holidays. Money much better spent on other things!!

[Andrew_C]

It is suggested that such equipment is given a regular visual check and a record kept of such checks. I check ours formally once a year, but obviously informally every time I am in the relevant cabinet.

Agreed. You can test IEC cables if there is risk that they may become damaged.

The key thing is that you do not have to be a fully qualified electrician to carry out these tests, but I would strongly suggest you do the course.

You need to be "competent". You could go to your local Technical College (or whatever they are called this week) and do a City & Guilds course. Also about £100, one day plus a one hour multi-guess exam.

[OutToLunch]

So, I've got the shiny C&G certificate but am then given a cheap and cheerful PAT tester unsuitable for ICT/electronic equipment, at which point I pointed out the part in the instructions saying "Not suitable for PCs" and refused to zap any of my gear with a 20 amp current.

 

Does anyone here personally test their ICT gear with a proper low current tester, or do you rely on the guidance above about not having to physically test it? I believe the member of our maintenance who currently does our PCs just tests the IEC leads, but have a feeling he's quite happily zapping speakers, printers etc with a full current test :S

 

I was looking at swapping the tester I'd been given for something like the Seaward PAT500H, but from the comments above am now wondering if it's worth it...

 

http://www.pat-training.co.uk/seaward_pat_500H_tester.htm

[Andrew_C]

I do test some ICT type stuff with the 100mA test on a Seward. What we tend to do is test the with the PC and cable tie them together. We don't test ICT stuff annually, but this may change as clueless manglement have got in a contractor to do some of the stuff, but without any reference to us...

[Sylv3r]

All of ours are tested by the LEA PAT testing team.

 

They are here at the minute. They generally leave the IT Suites a mess, so they dont get a chance to get near my servers or switches here.

 

Takes a team of 5 - 2 weeks to do the full school - surely this is only going to get worse and not better when more PC's etc are brought in.

[tickmike]

I was horrified when I went along to the charity run school I look after today and found that someone had P.A.T. tested all the IT equipment without asking my advice first.(strong word with the head needed !) Being a fully qualified Electrician I understand what can happen to sensitive electronic equipment .

What the 'PAT' tester does is to apply Twice the operating voltage eg. for 240/250 volt.50 hz equipment so 500 V .DC. would be applied across :-

say if you tested an IEC lead

a.. 500V live to neutral conductor.

b.. 500V live/neutral to earth .

c.. current of about 20 amps from one end of the earth cable to the other eg. mains plug to IEC socket.

You would also check to see if the mains plug fuse is of correct size, all terminals are tight,any damage to equipment or leads etc.

When I worked in a research lab I looked after and I tested many electrical items and the major problem was poor earths eg. the earth lead from the mains lead connected to the equipment chassis strait on to a painted surface.

Items with surge suppressors in can be damaged.

 

Test the leads only.

[MkII]

A valuable piece of advice I think TM!

[CyberNerd]

electricians who are contracted for our PAT testing do visual inspections on our network switches and make sure the cabinets are earthed.

[Andrew_C]

What the 'PAT' tester does is to apply Twice the operating voltage eg. for 240/250 volt.50 hz equipment so 500 V .DC. would be applied across :-

say if you tested an IEC lead

a.. 500V live to neutral conductor.

b.. 500V live/neutral to earth .

c.. current of about 20 amps from one end of the earth cable to the other

Test the leads only.

There is test equipment available that has a 100mA earth bond specifically for IT equipment. You should also be able to inhibit run tests for PCs due to the possibility of damage when the test is over, as the disks will still be being read during boot.

[Joedetic]

We used to have the DT tech do the pat testing (ages ago) and then the LEA decided that it was biased having someone internal do it and they now come in to do it. All the switches that have been taken out of old cabs as part of our new build didnt have any tested stickers on them, or the IEC leads, so draw whatever conclusions from that you want.

 

Although...all the lighting equipment was tested...even the stuff that had a huge 32Amp blue circular plug thingy on the end, and that was bolted to the wall at the time.

[Andrew_C]

In truth, I'm not sure I would consider a rack mounted switch "portable" within the meaning of the regs/guidance notes. However, the H&SAW act requires a "safe system of work" and for this you will need to be sure that the kit is safe which is difficult if you don't undertake some form of risk-based testing. Perhaps not every year, especially if the equipment is never moved.

 

As for lighting equipment, the risks of damage or deterioration in use is much higher so the testing needs to be thorough and frequent (at least annually). Oh, BTW, 32A isn't really huge on lighting kit; 400A single-pole connectors with 35mm² cables are the "big-boys' toys", 5 separate connections for a 3Ø supply!

[Joedetic]

yeah...well this is 20+ year old kit...32A was huge at the time

[tickmike]

Point of Interest.

When I was a Electrical Apprentice (a long time before the PAT tester ) you used a 'megger', we used a 5000 volt one to do some tests and as apprentices you bet your mates how long you could hold the leads and turn the handle (I know now why I have no brain) it made you eyes light up !!!.

I still have one of the older ones of my fathers from the second world war and it still works, its got a handle on it you turned to generate the voltage to do the test and a meter scale on the top which is calibrated in meg ohms.

After them you had the battery powered 'megger' .

[sparky2488]

I was horrified when I went along to the charity run school I look after today and found that someone had P.A.T. tested all the IT equipment without asking my advice first.(strong word with the head needed !) Being a fully qualified Electrician I understand what can happen to sensitive electronic equipment .

What the 'PAT' tester does is to apply Twice the operating voltage eg. for 240/250 volt.50 hz equipment so 500 V .DC. would be applied across :-

say if you tested an IEC lead

a.. 500V live to neutral conductor.

b.. 500V live/neutral to earth .

c.. current of about 20 amps from one end of the earth cable to the other eg. mains plug to IEC socket.

You would also check to see if the mains plug fuse is of correct size, all terminals are tight,any damage to equipment or leads etc.

When I worked in a research lab I looked after and I tested many electrical items and the major problem was poor earths eg. the earth lead from the mains lead connected to the equipment chassis strait on to a painted surface.

Items with surge suppressors in can be damaged.

 

Test the leads only.

 

Fully agree with what could happen to a PC with 500Vdc to a PC but any PAT tester worth his salt will test all full voltage PC's.... having said that though if you are only testing the IEC lead then you are not fully ensuring the equipment has a correct earth bond, this should be an instant fail for a class 1 PC as you have only carried out half the test. Dependent on the PAT tester used, there should be the facility to reduce the current to 100mA for Class 1 IT Equipment, my Seaward has inbuilt preset tests which include the 100mA drop and has never popped a PC yet.

[plexer]

6 year old thread

 

Ben

[sparky2488]

6 year old thread

 

Ben

 

Ha ha . . . didn't even notice that