Poll

How many cycles will the KeySight U1281A's detent spring last?

0-2000
7 (17.9%)
2k-4k
5 (12.8%)
4k-8k
14 (35.9%)
8k-16k
7 (17.9%)
>16k (most rubust meter ever made)
6 (15.4%)

Total Members Voted: 36

Author Topic: Handheld meter robustness testing  (Read 1149670 times)

0 Members and 5 Guests are viewing this topic.

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
Lifetime by itself doesn't mean anything. It has to be qualified for the product. Is it 5 years, 10 years, 20 years, 50 years after purchase? Is it transferable from one owner to the next?
Word of mouth is not legal, they should refer you to their proper lifetime definition on their multimeter documents.

Gossen warranty: (3 years)
https://www.gossenmetrawatt.com/english/seiten/warrantyconditions.htm
« Last Edit: October 17, 2015, 05:53:36 pm by Wytnucls »
 

Offline joeqsmithTopic starter

  • Super Contributor
  • ***
  • Posts: 11630
  • Country: us
I have never attacked Joe or yourself personally in any way.   .................
The term 'Fluke fan boy' (his spelling) was used by Joe in an earlier post than mine (post 496)(1). Did you feel insulted? I didn't think so; it just characterizes people who are passionate about a particular item. Dave himself used the term UNI-T fanboys, referring to people who defend their meters, like myself.  ................ He certainly didn't convey to me that he felt insulted by anything I said.

It was not my intent to insult anyone with the Fluke fan boy comments and I certainly would not take any comments directed towards Brymen fan boys as an insult towards me.      As you state " characterizes people who are passionate about a particular item" was the intent of the comment.   

Quote
If anything, I have a lot of respect for Joe for being able to build a quality high voltage tester at such short notice and for fixing multimeters as fast as I can tie my shoelaces.

If my trouble shooting abilities make things seem simple, it is only because I have damaged so much stuff over the years!!!    :-DD  But, thanks.   


I treated all brands with equal prejudice (as far as the testing).  Sure I may be biased against Fluke and made that clear from the start but the reality is that all meters are tested the same.   Or at least I attempted to test them all the same.    In the end, twice now I have had to eat crow as I watched yet another Fluke out survive fifteen additional meters.   Even worse, again watching my favorite, shinny new Brymen, that came all the way from Poland,  which cost much more, being damaged in the name of science. 

The Fluke (and argueably the Brymen also) is just not robust enough.......do some power electronics with contactors or large inductors and subject a meter to back EMF and poof.  :wtf:

We've all made DMM range selection errors and subjected our meters to all sorts of abuse, sometimes it is just supidity, other times unexpected voltages. That the meter should protect you as per CAT or IEC ratings is a given, but simple user errors should not result in a  :-BROKE  :-DMM

For entry level meters to survive and flagship models not.  :wtf:

Yep. I was messing about with some little Neon lamps the other day and when there's no load on my little 5V->150V transformer the output goes over 1000V, no problem.

(As measured with a $5 meter set to 1000V mode. It survived the spark...)

Yes, you have to set the Fluke 87V to Ohms mode to kill it that way, but still...not good.

What you both are talking about has everything to do with why I am running these tests.   Watch a review and the meters may be taken apart and plugged into a wall socket at best.  Don't get me wrong, these people doing these reviews provide some very helpful data.   But if I buy a meter I want to know that the thing will survive some basic mistakes.   I would expect for many people, this will not be important.   It's hard to damage a meter looking at digital logic and car electrical system and maybe plugging it into your household wall socket now and then.  Sad that some meters I tested could not even survive this! 
 
Quote
I just happen to disagree with the way Joe is conducting tests on multimeters and inferring from them that the Fluke 87 is a lesser meter than the Fluke 101.

Quote
Any test engineer or working scientist knows that you can't draw any meaningful conclusion from testing with an n=1 (or 2) - so all this teeth gnashing about exactly what these tests ultimately prove is misplaced IMHO.  They are certainly interesting and entertaining and make for a good discussion. I say well done Joe! (even though I know he has not tolerated my critique in the past).  Joe's biases come through but that is not a criticism - we all have our biases.  Any strongly held opinions about the  87V based on these tests are unfounded IMO but that's ok - we all have opinions..

In the first series of meters I mentioned that I had only tested one of each meter and that this was not much of a sample size.  Obviously, we are never going to be looking at large same sizes for any of these reviews.    Many benchmarks are performed with minimal sample sizes and in some cases, even one sample  but it does not mean they are completely invalid or that we can not learn anything from them.   Statisticians are rolling there eyes now..... 

Let me start by saying that these products were obtained through normal channels.  In most cases they were procured through Amazon.   Why does this matter?  Well, if say the manufacture sent me meters directly for these tests, how would we know that these products were not special in some way in order to bias the tests?  So to be clear, in no case did Fluke or Brymen supply me with product for these reviews.   This is what I don't like about regulatory groups.  The companies ship the products to be evaluated.  Many times these may not be the final production parts.   They may need to make some changes and go back and forth a few times before they are certified.    In the end, do we really know the product that was certified is what will be supplied to you and me?  Or, will a MOV be removed to increase profits by some accountant.   Maybe a part was changed out for a cheaper part of what they think is the same quality and the product was not re-certified because of cost, time, etc.     So, because I obtain the meters my some means that the average person could,  I am making some assumption that the meters I test represent the average meter.     

Now this makes for another assumption.  I assume that the manufacturer has their process under control.    They may not and then my first assumption that my one meter represent the mean goes out the window.      So we could say for example, the 87V I tested does not represent the average 87V.  It was some outlier.  Then we also say that Fluke does not have control of their process.    Now I doubt they have a process control problem, but I don't know.  I would more guess that the meter just does not handle the transient by design in these other modes besides voltage.   It's a pretty old design when compared with the 101.  I am sure they have learned a few things and have improved their designs.   I have no data to back that up and am just giving them the benefit of the doubt. 

In the case of the 101 being the only meter to survive my first round of testing, we had a member repeat these tests using a different meter and commercially available transient generator.    The results were the same.   Even at 12KV they could not damage the 101.   I went further and increased the FWHH and added 1KV and still could not damage it.    I have some level of confidence that the 101 is very robust.   That said, I was not too surprised that the 107 survived this same test.     

Now had say the Fluke 87V failed at 2KV and the Brymen BM869s at 2.5KV, I would say we are well withing the margin of error of my tests and the meters them selves (what brand of components, date codes, etc).  But this is not at all what happened.   We have one meter living at 6KV and one failing at 1.5KV.    That's a pretty big window.   I bet if I tested 100 pcs of each meter we could find some 87Vs that would live to 1.7KV and some Brymens that fail at 5.5KV.      If the windows were much wider, I would really question their process and quality control. 

The problem in gaining confidence in the tests is that we are no longer talking about low cost meters.   I doubt that our members are going to run out and buy an 87V and BM869s knowing the 87V may be damaged at 1.5KV just to repeat the test and see which is more robust.     

I don't believe I have skewed the results or biased the test towards one brand or another.     Again, take it for what it is worth or feel free to step up to the plate and take a swing.   I am open to what ever tests the group can come up with to help determine which meters are more electrically robust than others.   

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 16561
  • Country: 00
For what it's worth, I can't think of any high-end meter that has an overvoltage protection above 1000V on the Ohms range. And I've read a lot of manuals to compile the multimeter lists.

So...if you're poking around unknown devices (even battery powered ones) it's better to use Flukes cheapest meter instead of their flagship.  :-//

« Last Edit: October 18, 2015, 07:31:45 am by Fungus »
 

Offline 5ky

  • Regular Contributor
  • *
  • Posts: 186
  • Country: us
So much salt, and no popcorn!
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
Lifetime by itself doesn't mean anything. It has to be qualified for the product. Is it 5 years, 10 years, 20 years, 50 years after purchase? Is it transferable from one owner to the next?
Word of mouth is not legal, they should refer you to their proper lifetime definition on their multimeter documents.

I agree with you, it is not clear. The definition of "useful life" can be defined as the period over which a capitol purchase is discounted to zero value for the purposes of tax write offs. This still doesn't help much but most companies would write off a multimeter after 5 years. I don't think that this is the definition that Greenlee is using based on my conversation with their service rep.

I am sorry, but the clearest answer I got from Greenlee service is that they will replace almost anything as long as it has failed not by fault of the user. A verbal agreement is as good as a written contract if you can prove the verbal agreement occurred, with a recording for example. I suppose that some boss at Greenlee could say that their employee overstepped his bounds and they will not honor his agreement.

The point is, IMHO, that Greenlee does have a lifetime warranty and it might not be as clear as some others, but the others also have lots of room to deny the claim also as has happened to some here. The room to avoid a warranty claim also exists in the Gossen link you showed. I have no vested interest in Greenlee.
 

Offline oldway

  • Super Contributor
  • ***
  • !
  • Posts: 2172
I have several Fluke multimeters and a 87V.
It is my favourite multimeter but I use it only as a bench meter.
For field service, I am using an old Fluke 73 that I bought in 1993.
There is a good reason for this.

Fluke 87V is far too expensive in Europe (more or less 500€). :--
Even used, it's hard to find one cheaper than 250€

My first 87V has been stolen during field service...It is highly risky because his high value. :scared:

If you don't need to have all the features of a 87V, the 101 seems to be a better option for field service.
Another option is the Brymen 869S that is not as well known as the Fluke 87V and is a lot cheaper for the same safety and features.

To be a real winner in Europe, Fluke should sell his 87V at the same price range as the Brymen 869S, I mean between 200 and 250€  :popcorn:
« Last Edit: October 18, 2015, 07:21:12 am by oldway »
 

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
Lifetime by itself doesn't mean anything. It has to be qualified for the product. Is it 5 years, 10 years, 20 years, 50 years after purchase? Is it transferable from one owner to the next?
Word of mouth is not legal, they should refer you to their proper lifetime definition on their multimeter documents.

I agree with you, it is not clear. The definition of "useful life" can be defined as the period over which a capitol purchase is discounted to zero value for the purposes of tax write offs. This still doesn't help much but most companies would write off a multimeter after 5 years. I don't think that this is the definition that Greenlee is using based on my conversation with their service rep.

I am sorry, but the clearest answer I got from Greenlee service is that they will replace almost anything as long as it has failed not by fault of the user. A verbal agreement is as good as a written contract if you can prove the verbal agreement occurred, with a recording for example. I suppose that some boss at Greenlee could say that their employee overstepped his bounds and they will not honor his agreement.

The point is, IMHO, that Greenlee does have a lifetime warranty and it might not be as clear as some others, but the others also have lots of room to deny the claim also as has happened to some here. The room to avoid a warranty claim also exists in the Gossen link you showed. I have no vested interest in Greenlee.
This is Brymen's warranty terms. I don't see much difference compared to the limitations of Fluke's or Gossen's limited warranties. I expect Greenlee's warranty will follow the same guidelines. No company will cover the cost of repair for an item that has been misused by the user, unless by prior arrangement or goodwill on their part. (UNI-T fixed my multimeter under their 3-year warranty, even though I had modified it extensively):

LIMITED WARRANTY
BRYMEN warrants to the original product purchaser that each product it manufactures will be free
from defects in material and workmanship under normal use and service within a period of one year
from the date of purchase. BRYMEN's warranty does not apply to accessories, fuses, fusible
resistors, spark gaps, batteries or any product which, in BRYMEN's opinion, has been misused,
altered, neglected, or damaged by accident or abnormal conditions of operation or handling.
To obtain warranty service, contact your nearest BRYMEN authorized agent or send the product,
with proof of purchase and description of the difficulty, postage and insurance prepaid, to BRYMEN
TECHNOLOGY CORPORATION. BRYMEN assumes no risk for damage in transit. BRYMEN will,
at its option, repair or replace the defective product free of charge. However, if BRYMEN
determines that the failure was caused by misused, altered, neglected, or damaged by accident or
abnormal conditions of operation or handling, you will be billed for the repair.
« Last Edit: October 18, 2015, 10:35:50 am by Wytnucls »
 

Offline joeqsmithTopic starter

  • Super Contributor
  • ***
  • Posts: 11630
  • Country: us
So much salt, and no popcorn!

It seems you are not satisfied with the damage I have inflicted on your meters and I would hate to think I had an unhappy customer.   So, last night I tore the old generator apart and rebuilt some of the circuits to handle even higher levels.   Today I will find the limits of your Fluke 107.

That's a 20KV 50us FWHH wave there with about 15J available..   



Offline Fungus

  • Super Contributor
  • ***
  • Posts: 16561
  • Country: 00
Today I will find the limits of your Fluke 107.

Are we placing bets...?  :popcorn:

That's a 20KV 50us FWHH wave there with about 15J available..

Does it go up in steps or are we going straight to 20kV?
 

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
This will be all up to the MOVs (2x K575 13 26 7mm). Should be able to handle 35 Joules @ 8/20uS, clamping at 600V.
Overvoltage protection is set at 600V on voltage only. No mention of protection on other ranges.
Unfortunately, the clamping ability deteriorates with each transient pulse.
« Last Edit: October 18, 2015, 05:53:16 pm by Wytnucls »
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 28139
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
I hate working with lead free solder.
Then why on earth do you? It's muck.
Avid Rabid Hobbyist
Siglent Youtube channel: https://www.youtube.com/@SiglentVideo/videos
 

Offline joeqsmithTopic starter

  • Super Contributor
  • ***
  • Posts: 11630
  • Country: us
Because everything is built with that crap now, including this 107.   On the bright side, if I have the heat gun out, you know something didn't go so well for 5ky's Fluke. 

Online tautech

  • Super Contributor
  • ***
  • Posts: 28139
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Because everything is built with that crap now, including this 107.   On the bright side, if I have the heat gun out, you know something didn't go so well for 5ky's Fluke.
Oh dear.  :o  :-DD
Your improved evil lady is truly wicked.  >:D

Will the 101 survive and be top of the heap?
Avid Rabid Hobbyist
Siglent Youtube channel: https://www.youtube.com/@SiglentVideo/videos
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
I don't understand why anyone would use lead free solder for hobby work.  :scared:

I am interested in seeing the new beast at work. I wish I could get parts here easily to build something too. In Chile, the parts supplies are sparse and delivery times from around the world take months.

Upon reflecting on all the testing, I have a couple of comments if I may. (I know, when have I asked permission before? :) )

The Digitek/Tekpower has a space for an MOV. This would have definitely saved the meter from some damage IMHO, but it would not save the user in a real life big fault. It would be across the inputs directly without current limiting and could make a BIG bang if the meter was subjected to a high voltage surge while connected to a CAT III condition. Maybe that is why it was left out. It exists in my DT2843R meters and it would be interesting to see what would happen.

The title of this thread is "Hear kitty kitty kitty, nope not that kind of cat. CAT III handheld surge tests." This could mislead people to think that these are proper CATIII surge tests. Joe has already said many times in the thread that this is not the case, but it still remains in the title.

It is still in dispute whether a meter needs to survive and function after the fault conditions as spelled out in the IEC requirements for multimeters, or if they only need to not cause harm to the user when the fault occurs. ( Yes Joe, your tests are not to prove this nor anything other than your criteria for what is a robust meter).

From Joe's tests, no meter can be said to pass or not pass the IEC requirements since we do not know whether the meter needs to still function or only protect the user from harm as mentioned above. It probably can be said that certain meters would certainly fail the IEC requirements from the damage incurred by Joe's tests, which would predict a big flash over.

An lastly, Joe has spent a huge amount of time and some considerable expense to do this testing. 5KY has also spent some real money. They are electronics nerds to be respected! :)
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
Because everything is built with that crap now, including this 107.   On the bright side, if I have the heat gun out, you know something didn't go so well for 5ky's Fluke.

That doesn't mean you need to continue to use lead free. Dilute the lead free with lead containing solder and be done with it!
 

Offline joeqsmithTopic starter

  • Super Contributor
  • ***
  • Posts: 11630
  • Country: us
Because everything is built with that crap now, including this 107.   On the bright side, if I have the heat gun out, you know something didn't go so well for 5ky's Fluke.
Oh dear.  :o  :-DD
Your improved evil lady is truly wicked.  >:D

Will the 101 survive and be top of the heap?

I doubt I will run the 101 until I find another brand that I feel will outperform it.   One thing is for sure, that Fluke 107 is one tough little meter.  If you are blowing these up on your hobby bench, tell us all about it!    Even if you just blew up your Brymen BM869s, I would like to hear details about what you did.     No need to tell us you damaged your 87V playing on your bench.  :-DD   
 
I don't understand why anyone would use lead free solder for hobby work.  :scared:

That doesn't mean you need to continue to use lead free. Dilute the lead free with lead containing solder and be done with it!

:palm:  No offense but I find how you derive conclusions very fascinating.  :-DD  The next video may help you understand my comment. 

I hope to have it up in a couple of hours.   Poor little Fluke never stood a chance....

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
I don't understand why anyone would use lead free solder for hobby work.  :scared:

That doesn't mean you need to continue to use lead free. Dilute the lead free with lead containing solder and be done with it!

:palm:  No offense but I find how you derive conclusions very fascinating.  :-DD  The next video may help you understand my comment. 

I hope to have it up in a couple of hours.   Poor little Fluke never stood a chance....

I meant to quote this:
Quote
Quote from: joeqsmith on Today at 06:06:44 AM

    I hate working with lead free solder.

Then why on earth do you? It's muck.

I only was agreeing with Tautech.
 

Offline joeqsmithTopic starter

  • Super Contributor
  • ***
  • Posts: 11630
  • Country: us
Most anything now days is some form of lead free.  If you watched my last couple of videos, you may have noticed I will at times use a Weller heat gun.  Some of the lead free solders have a pretty high transition temp that require me to throw heat to the PCB longer than I would like.   This is where my comment came from.   Putting the parts back is no problem but I don't mix lead free and lead solders.  Nor do I mix no clean and rosin.   :blah: :blah: :blah:

But I do damage meters..
5ky's Fluke 107 takes a  hit for science and somehow, I feel real good about watching it die!   


THIS IS ONE TOUGH METER!!!!! 

Now that I have an idea where the 107 fails, I would love to put a 28 and 298 on the chopping block.     

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
I would be interested to see a 28IIEX put through these tests, as well as the Amprobe HD160C. Maybe we can come up with a group donation to add more meters to the junk pile.
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 28139
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
I would be interested to see a 28IIEX put through these tests, as well as the Amprobe HD160C. Maybe we can come up with a group donation to add more meters to the junk pile.
+1
Fluke 15B is the meter I'd like to see play with the evil lady.
I can get one to Joe for USD75 and happily pay half.
Any takers?

15B, 17B same internals.
« Last Edit: October 19, 2015, 08:05:52 am by tautech »
Avid Rabid Hobbyist
Siglent Youtube channel: https://www.youtube.com/@SiglentVideo/videos
 

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
It is still in dispute whether a meter needs to survive and function after the fault conditions as spelled out in the IEC requirements for multimeters, or if they only need to not cause harm to the user when the fault occurs.
From Joe's tests, no meter can be said to pass or not pass the IEC requirements since we do not know whether the meter needs to still function or only protect the user from harm as mentioned above. It probably can be said that certain meters would certainly fail the IEC requirements from the damage incurred by Joe's tests, which would predict a big flash over.

I suspect that, after reading several manufacturer's operating manuals, meters with a proper CAT rating should still operate correctly after the relevant high voltage transient tests, but applied on voltage ranges only. Other ranges should survive a voltage equal to their highest CAT rating voltage.
The final test may consist of subjecting all ranges to transients also (to check for damage containment), but it is not confirmed yet.
Amps ranges are tested for creepage, with ruptured fuses in place, while double the CAT rating max voltage is applied for 1 minute.
« Last Edit: October 19, 2015, 08:57:51 am by Wytnucls »
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 16561
  • Country: 00
Fluke 15B is the meter I'd like to see play with the evil lady.
I can get one to Joe for USD75 and happily pay half.
Any takers?

15B, 17B same internals.

I was thinking the same thing (but one of the newer 15B+ and 17B+ versions...)

Also ... one of those old-school Fluke 27s. They're supposed to be pretty tough but I wonder if they'd hold up or not.
« Last Edit: October 19, 2015, 01:51:10 pm by Fungus »
 

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
The Amprobe HD160C won't fare any better. Overvoltage protection 1500Vdc or 1000Vac on all ranges. Transient protection on voltage ranges only:

Transient protection: 12 kV impulse (1.2
uS/50 uS) based on EN 61010-1:2001 impulse
requirement for at CAT IV 1000 V/1500V dc
product. This product should not be used in
installations where transients exceed 12 kV.
 

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
This is the overload protection layout for the Fluke 87 (Early 1989 model):

For Volt/Ohm/Diode ranges:
2 MOVs 910V (RV1 RV2)
3 current limiting resistors R1(1kOhm 2W fusible opens for high energy signal) R2(909K 2W)  RT1(1.5K PTC goes to high impedance for sustained voltage overload for mVdc/Ohm/Diode)
1 spark gap (E1) 1500V

For Ohm/Diode ranges:
1 voltage clamp circuit: 3 NPN transistors (Q1 Q2 Q6) 2 diodes (CR7 CR8) 1 resistor (R58) 120kOhm
limits the overload current to U4(ADC) to a maximum of 10mA.

« Last Edit: October 20, 2015, 08:46:21 am by Wytnucls »
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 16561
  • Country: 00
If people are really interested in testing more meters, maybe we could do a Paypal account or kick start for each meter people want to run.
Paypal would be OK.

Kickstart takes ages and takes a big comission.

We need to know how many people are interested though. Let's have a show of hands...

 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf