Does anyone use the UNI-T 528 test tool

[Desmond Downs]

I'm wondering if anyone has used this tool.
First of all I'm an automotive electrician but my work sent me on a PAT testing course and we have a DeltaPAT mi3309BT unit at work.
I was thinking of buying something cheaper like this tool just to experiment with at home. I am 8 years away from retirement and was thinking about the possibility of doing PAT testing as a 'semi retirement' job. At the current cost of testing items 10 an hour would earn me 1 1/2X my current hourly pay.
I don't want to spend 4X the money on a DeltaPAT which would sit gathering dust for 8 years - I could consider buying one when the day comes for retirement if I'm still going to do it but for now that money is better off going into my mortgage.
For now I'm thinking that this UNI-T tool would be useful to have around and experiment with. Does anyone use one?

 

[PenllŷnShan]

Hi! I am a new PAT tester and use the UT528. It's simple to use and seems fine for everyday purposes like basic offices/holiday lets/caravans/nurseries etc...
It's battery powered so very portable , and lightweight too.
Some more experienced people seem to think it's "cheap chinese c**p", but it is working ok for me so far.
I find testing more complex items, like long extensions, adapters, and commercial large fridges a bit of a problem. It kept failing a chiller yesterday, yet an electrician today says it's passed for him without a problem. (I am a bitt suss of this though, as he is friends with the customer!)
So, that's my feedback! I'm happy , on the whole, but will upgrade when I can afford.
I am using the Kewpat app as well, so will probably go with one of their machines in due course.
Good luck! I am surprised how many people are looking for testers, and am making good money.

 

[James]

when you say it failed a chiller, what was the fault?
could it be that one or other of the testers is out of calibration?

 

[PenllŷnShan]

when you say it failed a chiller, what was the fault?
could it be that one or other of the testers is out of calibration?

Hi James, no my tester is new and was oly calibrated in February this year.

when you say it failed a chiller, what was the fault?
could it be that one or other of the testers is out of calibration?

 

[davesparks]

It's battery powered so very portable , and lightweight too.

And presumably not capable of doing a proper bond test and any sensible level of current if it is only battery powered?

It kept failing a chiller yesterday, yet an electrician today says it's passed for him without a problem.

Which test did it fail? What was the test result and was it close to the pass value or nowhere near it?

The test equipment can't decide whether something passes or fails, it is just a dumb machine, you, the person doing the testing, makes the decision based on the test results.

 

[PenllŷnShan]

And presumably not capable of doing a proper bond test and any sensible level of current if it is only battery powered?


Which test did it fail? What was the test result and was it close to the pass value or nowhere near it?

The test equipment can't decide whether something passes or fails, it is just a dumb machine, you, the person doing the testing, makes the decision based on the test results.

Thanks
Am well aware decision to fail/pass is mine as the tester! However, without a reading to assess , hard to make that decision!
It failed the earth continuity test, just showed a straight fail, no reading, as if I wasn't getting an earth, despite using my "prong" on every available metal surface. I wondered if perhaps I needed to adjust for cable length in some way? I did replace the fuse in case that was the issue. The chiller was stored in a barn wrapped in plastic but was working when I plugged it in.
As a new tester, with just a basic test machine, I was merely asking for advice. I never pretend to be an electrician.
Cheers

 

[James]

Thanks
Am well aware decision to fail/pass is mine as the tester! However, without a reading to assess , hard to make that decision!
It failed the earth continuity test, just showed a straight fail, no reading, as if I wasn't getting an earth, despite using my "prong" on every available metal surface. I wondered if perhaps I needed to adjust for cable length in some way? I did replace the fuse in case that was the issue. The chiller was stored in a barn wrapped in plastic but was working when I plugged it in.
As a new tester, with just a basic test machine, I was merely asking for advice. I never pretend to be an electrician.
Cheers

Was it definitely a class 1 appliance?

 

[PenllŷnShan]

Was it definitely a class 1 appliance?

It is a huge commercial type chiller with a 13 amp fuse in standard plug. Nothing to say Class 2 so tested as Class 1 as per my training. It had an earth wire attached to it's casing underneath, like you see outside houses sometimes attached to a rod? I assumed as most fridges and freezers are Class 1 this one would be too?

 

[James]

I would start by checking for the existence of an earth wire in the plug.
then look in the machine to see if it is terminated to anything.

 

[davesparks]

It failed the earth continuity test, just showed a straight fail, no reading, as if I wasn't getting an earth, despite using my "prong" on every available metal surface.

If the tester just shows 'fail' and doesn't also give a measured value then I would say that the tester is not fit for purpose.

wondered if perhaps I needed to adjust for cable length in some way?

It may that the test limits aren't set right in the tester, but without a measured value of resistance you cant really know.

I did replace the fuse in case that was the issue.

But the fuse isn't part of the earth path being tested, you can pass an earth continuity test with the fuse removed.

The chiller was stored in a barn wrapped in plastic but was working when I plugged it in.

That's a bit worrying to be honest, if an appliance fails testing then it should not be plugged in!

 

[PenllŷnShan]

I would start by checking for the existence of an earth wire in the plug.
then look in the machine to see if it is terminated to anything.

Definitly has an earth wire lol. What do u mean by terminated to anything?

 

[James]

Definitly has an earth wire lol. What do u mean by terminated to anything?

What is the earth wire connected to a screw terminail?

 

[PenllŷnShan]

What is the earth wire connected to a screw terminail?

It was screwed via a tab at the end of the earth wire onto the metal frame of the chiller
Sharon

 

[James]

you should be able to measure earth continuity from this point to the 13A plug, if no continuity then replace cable.
however I am surprised that you would plug it in after discovering a fault in the earth.

 

[PenllŷnShan]

you should be able to measure earth continuity from this point to the 13A plug, if no continuity then replace cable.
however I am surprised that you would plug it in after discovering a fault in the earth.

I was unable to test the earth continuity...........my machine couldn't read it. Hence my query. I didn't plug it in, custmer insisted on doing so. And an electrician has apparently since been able to pass it. My query was why couldn't my UT528 test it? Was I doing something wrong, or was it outside my machine's capabilities?

 

[James]

You are misunderstanding, you should be able to measure the continuity of any piece of wire from one end to the other.
if you can’t read it on your tester, it is not there to read and is a fault either in your test method or the cable.

 

[PenllŷnShan]

You are misunderstanding, you should be able to measure the continuity of any piece of wire from one end to the other.
if you can’t read it on your tester, it is not there to read and is a fault either in your test method or the cable.

Thanks for your patience James. I am new to this so maybe don't use the right words. I do of course understand that I should be able to measure the continuity of any piece of wire, and that is exactly what I was trying to do with my UT528 on this appliance. Usually when I test it gives me a reading, which I can then see is either a pass reading or a fail. However on this occasion the machine was just saying "fail", no reading in numbers at all, wherever I attached the probe on the casing, which was all metal. So I was unsure whether it was reading it at all! Or a genuine fault. As it was later passed by another technician I assume I was doing something wrong and was merely trying to find out from you guys what, if anything, I should have been doing. I tested the machine at home on our own fridge and it worked fine, so not the machine. I wonder if I was either not attaching the probe to the correct place, or whether I needed to reset the UT528 for a longer cable or different voltage?
Thanks again

 

[DPG]

I have seen issues before where people rely on the test instrument saying 'Pass' or 'Fail'. But a tester should know what results to expect, and what they may mean when they are outside limits. There may be a need to perform manual tests in some cases.

 

[davesparks]

. As it was later passed by another technician I assume I was doing something wrong and was merely trying to find out from you guys what, if anything, I should have been doing.

It is at that point you just get your multimeter out and check for continuity between plug and the machines earth terminal and between the earth terminal and the suspect metalwork.