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.
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!!!
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. 
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 
For entry level meters to survive and flagship models not.
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!
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.
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.
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