PAT testing in situ

[steve1159]

I was out rigging some lights in a venue yesterday and noticed that although the in house lights had a current PAT test they were all covered in a layer of dirt from some work that was done during 2009 that had not been disturbed. Obviously the person testing could have carefully taken the light down to test but rather unlikely. Later on I was talking to the venue caretaker and mentioned it and apparently the person testing just goes up to each light on turn on top of a scaff tower and plugs it in with light still hanging on the bar. The venue are quite happy because they have the relevant certifacte so everything must be OK then!! Personally I would be very dubious how much of a visual inspection can be done with out even touching the light. Equally I am concerned about PAT testing in situ where as pat of the test current is passed through the device (including the earth e.g earth bond test, earth leakage test) which effectively means the whole lighting bar becomes live at the test current. Does anyone else test lights in situ like this or can give a reason why it is a good idea-I normally remove lights, clean them, visually inspect before plugging into the PAT tester and then rehang the lights at the end.

[Jivemaster]

Said venue probably values pat compliance by the smallest cost per item quoted by competing company quotes!

I could use uncertain WAH practises to get to lanterns and take a battery powered PAT machine up with me, However there would be no inspection time, but the cost per item might get me the job over someone pricing to do it correctly with inspection.

As ever it's cost vs product!

[mac.calder]

Seaward Primetest 350 - we have one at work, and we use it for testing in situ. We have a bluetooth printer, bluetooth scanner etc. Pulling down 168 moving lights and putting them back takes a huge amount of labor. This one, we go up in the lifter and drive to each light. Perform a visual inspection, unplug it, scan the barcode, plug it in to the Primetest 350, if it passes, a tag comes out the printer up in the lifter. Done. There is nothing you can do on the bench that you cannot do from the air.

 

http://www.seaward.co.uk/images/uploads/products/PT350%20web(1).jpg

 

That said, we tend to run tandem lifters, one following with an air compressor.

[Andrew C]

There are testers that can do (limited) tests on running equipment by plugging the tester into an adjacent socket, and interpreting results. Not that I think that this is what happened in this case, but don't rule it out!

[steve1159]

I was aware that some testers can do in situ tests via an adjoining socket (indeed my own tester can). For a device such as a computer sitting on an office desk then no issue. Bearing in mind most PAT test manuals contain a statement such as the following

 

"This Tester performs a number of electrical tests which involve high

voltages and high currents. Never touch the appliance being tested,

or the test leads, whilst a test is in progress."

 

and that carrying out a test passes a current down the earth wire(assuming class 1) and also applies a typical 500V for the insulation test does it raise concerns that an in situ test on a light hanging on a bar gives the potential for the bar to become live as part of the test which may result in a shock to someone else in contact with the bar. Having said that there are the practical issues as mentioned above of actually taking down a large number of movers etc

[PaulDF]

and that carrying out a test passes a current down the earth wire(assuming class 1) and also applies a typical 500V for the insulation test does it raise concerns that an in situ test on a light hanging on a bar gives the potential for the bar to become live as part of the test which may result in a shock to someone else in contact with the bar. Having said that there are the practical issues as mentioned above of actually taking down a large number of movers etc

 

I always thought that the continuity testing (earth bond test) is done at extra low voltage so as not to present a shock risk. The bond is checked before the insulation resistance so even if the IR is low, the earth bond is present and does not present a shock risk.

[themadhippy]

Equally I am concerned about PAT testing in situ where as pat of the test current is passed through the device (including the earth e.g earth bond test, earth leakage test) which effectively means the whole lighting bar becomes live at the test current.

what diffrence is this to installation testing,when you test the earth impedance of the bonding of the kitchen sink,how do you know someone isnt holding a tap upstairs?

As for testing in situ,at a previous venue the anual rig testing was done with the rig in thje air without any problems

[sleah]

I suspect the earth bond test is still acceptable when in situe because I would imagine the earth bond is with reference to the machine rather than real earth. So if the earth was broken somewhere along the cable it would still fail, even if the fixture was picking up real earth through it's mounting points.

 

Also if you think about it, if it's a fixture that just lives in the roof and not moved regularly, there isn't a great deal that can go wrong apart from insulation breakdown, so a basic external visual inspection is quite acceptable. A full inspection could be carried out every (say) five years, which is fairly normal practice where equipment is untouched for months or years at a time.

 

So it may be that the fixtures that are being tested in situe have been fully tested a couple of years ago and aren't due for a full test for a couple more.

 

We have IT suites (in a school) that are only fully tested every two years and just a visual in between, and everyone is happy

[Junior8]

Also if you think about it, if it's a fixture that just lives in the roof and not moved regularly, there isn't a great deal that can go wrong apart from insulation breakdown, so a basic external visual inspection is quite acceptable. A full inspection could be carried out every (say) five years, which is fairly normal practice where equipment is untouched for months or years at a time.

 

Good point. I've been out of the day to day grind for years now but was in it when the EAW regs came in.

 

I asked for guidance precisely on this issue since our largest space was so fixed that re-hanging would seldom if ever become an issue. I used to do most of the cleaning in situ with a full visual and earth continuity test when re-lamping or focusing.

 

I was told that as it stood the regs simply laid the usual reasonable duty of care on the responsible body but - and this is exactly what I had said to me at the time: "Every Tom, Dick and Harry will go out and buy a PAT tester and do their best to convince folk that they need every bit of kit tested annually. It'll be a nice little earner for them and a total waste of time, at least as far as safety is concerned." This came from a time-served sparks approaching retirement age in a senior role who reckoned a megger and good sense was all you really needed.The kind of chap that when he told you to do something - you did it!

 

In the end the school was convinced by the propaganda, sent a technician on a course and bought their own PAT tester and I had to take everything down every year - for it all to pass every time. Still it all had it's little ticket on it and I was fitter for the climbing so maybe it did do some good.

[Barreller]

On the subject of PAT but not exactly on this thread's subject, our local Am Dram unit has been told by a PAT tester that our lanterns do not require to be PAT tested because when installed they are not portable but need a mechanical mechanism (ie a spanner) to be removed. What's the general opinion of this one? My feeling is that it is rubbish and we need to test. Every lantern I have ever used has had the certificate on it.

[paulears]

This is the classic case of how the testing 'law' that everyone bandies about falls over. You make the case that by requiring spanners or other tools to remove an item, then it is no longer a portable appliance - it's a permanent feature, as with perhaps emergency floodlighting that is secured to the fabric of the building.

 

Certainly, by any reasonable interpretation, it's no longer a portable piece of kit, so the portable appliance test doesn't fit it any longer. However, the legislation and codes of practice people work to also recognises the need to test and inspect plant and other items at reasonable intervals - so it still needs testing, but probably by the general sparks who may come in to certify the rest of the electrical installation. It simply shifts responsibility. So it does not require a portable appliance test because it isn't one! You could apply the same rule to a chest freezer used to store ice cream if it had been permanently wired in through a spur box - as many are to prevent the cleaners unplugging them. It doesn't mean NO test, just a different one at perhaps a different time. Often used to exclude bits of kit that are awkward to get to, or even likely to fail in some venues!

[Simon Lewis]

My feeling is that it is rubbish and we need to test....

 

Your lights could be defined as fixed equipment (a category listed in the Code of Practice for In Service Inspection) or - as they could be moved to a different location and are under 18kg - portable appliances.

 

It doesn't really matter, as the overarching duty you have is to provide a safe system of work. Your duties under the Electricity at Work Regulations 1989 are:

(1) All systems shall at all times be of such construction as to prevent, so far as is reasonably practicable, danger.

(2) As may be necessary to prevent danger, all systems shall be maintained so as to prevent, so far as is reasonably practicable, such danger.

(3) Every work activity, including operation, use and maintenance of a system and work near a system, shall be carried out in such a manner as not to give rise, so far as is reasonably practicable, to danger.

(4) Any equipment provided under these Regulations for the purpose of protecting persons at work on or near electrical equipment shall be suitable for the use for which it is provided, be maintained in a condition suitable for that use, and be properly used.

This means that all of your electrical systems should be demonstrably safe to use, and the accepted way of doing this is portable appliance inspection and testing for devices that fit into the portable, movable hand held etc., categories and through periodic inspection for fixed wiring.

 

Given that your lights will need adjustment when operational (i.e. they will be handled while focussed etc.) and given that the high temperature environment means stress on cable, housings etc, I would suggest there is a particular requirement to carry out an appropriate safety test on a regualr basis. How regular your test is will depend upon the past history of testing and the risk associated with its use.

 

If you want an example of devices that the IET consider to be fixed items but are included in a PAT, they cite hot air hand driers and air conditioning units wired from a fused connection unit... not a 13A plug in sight, and they are screwed to the wall!

 

It looks like your appliance testers need to get up to date!

 

Simon