PAT testing using a multifunction meter

[Taylortwocities]

In many cases it is needed to avoid confusion. To pick up on BAS's example

Mississippi river.

Surely this is needed to avoid confusion with other occurrences of Mississippi

eg

State
Pop band
State university
Mud Pie

etc etc

 

[EFLImpudence]

Language evolves, in all sorts of ways and for all sorts of reasons. I've just had a quick look, and can't find any dictionary which does not include 'hoover' as a verb.

Fair enough, so you can hoover with a Vax.

When did you last install a 'Henley Block' made by Henley (if they still exist!)

Still around.

and when did you last refer to a 'Henley Block' (or even just 'Henley')?

I would never

I shall be careful in future to refer to it by the generic Toolstation Block.

 

[ban-all-sheds]

In many cases it is needed to avoid confusion. To pick up on BAS's example

Mississippi river.

Surely this is needed to avoid confusion with other occurrences of Mississippi

The problem is that Mississippi means "big river", so "Mississippi River" is "big river river".

"Sahara" means desert.

"Faroe" means sheep island.

If you want some closer to home, "Humber" means river.

And "bre" is the old Celtic word for hill, and "don" the old English word for hill.

So here's a photo of Hillhill Hill:

 

[JohnW2]

and when did you last refer to a 'Henley Block' (or even just 'Henley')?

I would never

I can't be bothered to trawl back through your posts but, even if that were true, I think you'd be in a small minority. TBH, I can't recall anyone having talked in terms of a 'service connector block', or anything like that, in this forum - even if very occasionaly, certainly not 'commonly'!!

Kind Regards, John

 

[ebee]

OK.

just do not Megger with a Fluke though

 

[SimonH2]

Also using 200ma rather than 25 amp to test continuity ...

But that's all many of the PAT units do - just a low current test. In fact, the one we have at work uses a lower current that that IIRC - I recall looking at the specs for it's pass/fail values with a view to using my MFT (for non-work stuff) should I leave the current job and no longer have access to the PAT unit.

There's also the issue of operator competence. The course material I've had basically suggests that the more interpretation required, the higher the skill level required. So with a basic tester that gives a simple OK/Fail result just needs a trained monkey who can do a visual and apply a bit of common sense. At the other extreme, using your MFT you need enough skill to judge what is OK or not when it gives you some values.


Also, it's rather timely that only the other day I was thinking of making a 13A socket in a surface box with three 4mm terminals (ie the reverse of the plug-in adapters like the Martendale SB-13). A number of uses come to mind - PAT being one of them, but yesterday I wanted to be able to connect a pair of probes to a 13A socket (I needed to run a fan heater from a pair of probes on terminals in a box*).

* Replaced UPS, want to test that the output wiring to the manual bypass switch is indeed capable of carrying current and won't dump the load as soon as I switch over. Yes it's a bit paranoid as I can't see any way for it not to be OK, but we have had a couple of "incidents" in the past. Of course I didn't consider plugging the SB-13 into a double socket with no wiring attached

 

[ericmark]

When in full time work I had a box of adaptors made to allow easy inspection and testing of many items both fabric of building and portable with a lock so no untrained person could borrow them. I am sure most have done the same.

However I was testing in-house so all had to be at some time tested by me. When working on a third parties building or equipment one has to only test what is in the remit. Since the order for work is often not made by an electrician often there are omissions and where the work is paid for by the items then one sees class III items included and item feed from FCU or other wise fixed to the building missed out where it would take too much time to test.

Where the tester points out the limitations this is not a problem but this does not always happen. So I will answer the question first as in-house tester.

I see no reason to buy a special machine for the job when in the main the normal testers will do the job. One over time has leads and other devices made to speed up the process. Where one can see a danger one is free to modify for example adding RCD sockets and as far as the HSE goes showing work is under way to improve will normally satisfy. So in-house one can use common sense and record the planned improvements.

However looking at third party work one really has no option but to follow the rule book. I don't have copy of latest book but early copies required 25A to test earth continuity except with IT equipment where the earth may be part of a printed circuit and using high currents could cause damage. I have personally not seen any damage either from 25A test or 500V test and would think in most cases equipment is designed to be tested and stand these currents for short times.

But even with third party work some personally consideration is required and one can't always follow the book to the letter.

There have always been questions raised as to what should fail and what should pass for an example a grinder with missing guard but electrical sound should one pass or fail the device. I have seen it said since one can't do a run test it should fail? However failing means it needs a re-test so be it fitting the guard or failing a lamp standard because it has no bulb would mean some one has to return to re-test once bulb is fitted it would seem sensible to pass the item allowing some one with the grinding wheel certificate to replace the guard.

There is always the case where some one picks up on mistakes or questions judgement. I when in University was give a project which asked at the bottom were there any health and safety issues. I thought there was one I was expected to highlight so looked carefully. I found the guard over the live terminals on the PLC did not need a key or tool to assess and the holes on the upper surface were larger then 1mm. Looking up manufactures data it stated it was designed to be used in an enclosure and should not be used free standing. I pointed out this including quoting the BS7671 regulation numbers.

It would seem it was standard wording and it was not expected that I would highlight the errors and it really put the cat amongst the pigeons. The third party testers where the ones brought to task a little unfair as for most of the time only skilled or instructed persons would handle the equipment. The guys doing the testing were expected to test around 200 items per day which does not really give any time to write comments like for use of instructed persons or above only.

I think there are enough problems with inspecting and testing of in-service electrical equipment without talking about if the phrase should be shortened to PAT testing or not. More to the point is "Portable" and "In-service electrical equipment" I am sure most clients think we are testing it all and to decide that item is over 28 lbs and has no wheels so I am not testing it specially where another easy to test item which is also fixed in some way is tested is wrong. At least without informing the client. Sloppy paperwork can also be a problem I saw where the paperwork from client refers to in-service electrical equipment yet paperwork from electrical firm refers to PAT testing clearly they did not want to call it in-service electrical equipment in case there was some large lump they could not test easy.

The standard paperwork I down loaded has a box to enter P, M, HH, etc. The explanation includes fixed and built-in as a type. Reading the form clearly this form should first be completed by the client as 19 (Authority) needs ticking by client before one is permitted to disconnect and client should also fill in register number, description, location, make/model, and date of purchase. In practice often reverse where the tester give the item a new number every time so it does not match the equipment register.

In conclusion in-house testing is easy. But third party testing is another ball game and one has to be so careful as to what is done. So in-house using standard testers is OK but not really for third party testing.

 

[Grizzly]

However looking at third party work one really has no option but to follow the rule book. I don't have copy of latest book but early copies required 25A to test earth continuity except with IT equipment where the earth may be part of a printed circuit and using high currents could cause damage.

Assuming you are referring to the IEE/IET Code of Practice when you say 'rule book', even back in the 2nd edition, it said that for earth continuity testing "Either of the following tests may be carried out:", then went on to describe both the 'soft' test (20mA - 200mA test current) and the 'hard' test (not less than 1.5 times the fuse rating, no greater than 25A).

So unless you're talking about the 1st edition (which I've not read yet), one test has not been required in preference to the other since at least 2001.

 

[ericmark]

I would agree the regulations say 200 mA minimum (612.2.1) and using 200 ma should not be a real problem. Also states voltage between 4 and 24 volt never actually checked on mine what it is. Can't find my copy of PAT testing book so will take your word for it that it says "Or". But clearly 20 mA would not comply. Seem to remember where a digital display is used there is a minimum time for the test to ensure steady reading not really required with analogue display but this means new set of batteries every day.

The batteries I keep in a plastic bag in same case but not in the meter in case they should leak so to test with continuity meter for me means a lot of messing around fitting and removing batteries so I often use the PAT tester rather than fit batteries. I may use meter 4 times a year. Now retired.

Speed is important with PAT testing. I found the top of range Robin good but slow as it was fully automatic and waited the prescribed time for each test this resulted in around a maximum of 100 items per day but with the simple Robin analogue tester I can look at 200 items per day. OK I have someone helping me scribe but it was the tester which was the limiting factor. One was the self test it did every time it was unplugged and plugged back in.

However I will admit it did highlight a number of faulty sockets but that was not what I was testing.

I have seen people walking around with battery operated PAT testers I would assume there is no run mode! To be frank the whole idea of running the machine under test is the whole point of using a dedicated PAT testing machine although one may have problems in both directions. The short run with computers often means they want to do full self test next time used. But many faults will not show until run.

 

[ebee]

I never got into PA Testing (or should I say appliance testing) but it strikes me that all folk are interested in are how fast they can do it not how accurately they can do a meaning full test to ensure safety.

When these tests first became vogue then people jumped on a bandwagon to make loadsa money, nowadays it`s how many million can I do a day at thrupence each.

A bit like the PIR (OK EICR nowadays) , all folk want is a quick cheap pass cert not a real reflection of the actual state of the installation.

 

[Grizzly]

I would agree the regulations say 200 mA minimum (612.2.1) and using 200 ma should not be a real problem

Don't start confusing the Wiring Regulations with the guidance for In-service I&T. They are not the same!
For In-service I&T, 200mA most definitely is not stated as the minimum.

But clearly 20 mA would not comply.

And yet it does.
I'd suggest you re-acquaint yourself with the correct guidance before making such misleading statements again.

 

[SimonH2]

I never got into PA Testing (or should I say appliance testing) but it strikes me that all folk are interested in are how fast they can do it not how accurately they can do a meaning full test to ensure safety.

What it comes down to it that many (most ?) customers do these tests because "they have to have stuff tested every year" - or at least that's what they believe. They don't really do it for safety, but as a means of covering their backsides - as in "yes Mr HSE guy, our employee did get a shock, but look here, it's been tested so it must be a new fault we can't reasonably have known about".

So when procuring the testing, they look at "how little can we get this done for". Hence those offering the service have to pitch on price - and so there's no profit for doing it properly, only for doing it fast.

Sadly, there's too much legislation to allow people to use common sense - it's one long string of stuff one has to cover your backside for.