Handheld meter robustness testing

[Wytnucls]

This was all discussed at length in a previous thread. https://www.eevblog.com/forum/projects/cat-ratings-and-interpretation/msg159305/#msg159305
In a multimeter, the only high voltage transient protection possible, if fitted, are MOVs or GDTs (gas discharge tube).
Good meters also have crowbar circuits to protect other ranges ( Ohms, caps, etc...) up to 1000V (with diodes or transistors). Cheaper ones, as per their user manuals, can often only cope with 250V max. (As mentioned by Meter Junkie, this protection must now match the max voltage CAT rating)
Another new requirement concerns fuse ratings. They must now be HRC fuses and must also match the max voltage CAT rating.

The test on the current ranges has also been modified and now consists of applying twice the max voltage CAT rating (2000V max), with a ruptured fuse in place, for 1 minute.
The high voltage transient tests remain the same.
There must not be any possibility of electrical shock, fire, sparking and explosion, during and after the test. Multimeters are not expected to function properly after the series of tests.

[joeqsmith]

In 61010-1 3rd Edition, the over voltage and surge tests have been removed. They are now covered in 61010-2-033 for DMM's and 61010-2-032 for clamp meters.

...

Of course, the better designed units can survive that over voltage, and still function.

61010-2-033 is what I quoted. 

The goal is the same no matter.  One meter will be more robust than the others. 

The Klein Tools MM500

In your video, you said you believed that Klein unit could survive higher than a 10 foot drop.  A quick google search returned this.

Dave also took that meter on his mud run, and it survived that.

I like the video!!  I had never heard of the brand until now. 

If I needed to have a very limited meter on a mud run to do some 1K resistor measurements, this would be it.       It's so light weight and solid, after these tests I may try and see what it takes to damage it.  Maybe drop it out of a plane or shoot it out of a cannon... 

[PedroDaGr8]

In 61010-1 3rd Edition, the over voltage and surge tests have been removed. They are now covered in 61010-2-033 for DMM's and 61010-2-032 for clamp meters.

...

Of course, the better designed units can survive that over voltage, and still function.

61010-2-033 is what I quoted. 

The goal is the same no matter.  One meter will be more robust than the others. 

The Klein Tools MM500

In your video, you said you believed that Klein unit could survive higher than a 10 foot drop.  A quick google search returned this.

Dave also took that meter on his mud run, and it survived that.

I like the video!!  I had never heard of the brand until now. 

If I needed to have a very limited meter on a mud run to do some 1K resistor measurements, this would be it.       It's so light weight and solid, after these tests I may try and see what it takes to damage it.  Maybe drop it out of a plane or shoot it out of a cannon... 

Klein is an american company that tends to focus on tools for electricians and telecommunications. I wonder who is manufacturing this meter for them. I am sure some others know of a few Korean multimeter companies. I can't think of any off the top of my head.

[retiredcaps]

Klein is an american company that tends to focus on tools for electricians and telecommunications. I wonder who is manufacturing this meter for them. I am sure some others know of a few Korean multimeter companies. I can't think of any off the top of my head.

Fine Instruments makes some of Klein's multimeters.  See

http://www.finest.co.kr/ci.html

Klein, however, has at least two multimeters that are "Made in the USA", but not for $50.

http://www.kleintools.com/catalog/multimeters/electricians-trms-multimeter

http://www.kleintools.com/catalog/multimeters/electricians-hvac-trms-multimeter

[Lightages]

It also looks like Klein gets a couple of their models from Mastech, at least from the appearance.
http://www.kleintools.com/catalog/multimeters/auto-ranging-multimeter

[tautech]

It's so light weight and solid, after these tests I may try and see what it takes to damage it.  Maybe drop it out of a plane or shoot it out of a cannon... 

Joe. Your disrepect of perfectly good test equipment worries me.
Some might say you are a sick puppy. 

Great thread, watched it all the way. 

[joeqsmith]

It's so light weight and solid, after these tests I may try and see what it takes to damage it.  Maybe drop it out of a plane or shoot it out of a cannon... 

Joe. Your disrepect of perfectly good test equipment worries me.
Some might say you are a sick puppy. 

Great thread, watched it all the way. 

  

I'm glad you are enjoying it.   

Today was a good day.  The unbranded DM-301 has finally been beat!  Not to mention, it was put to rest.  I am sorry to say that I did not catch it on video.  I forget to press record.    

For those who are concerned about how the meters are holding up.  Here's the final six meter getting hit with a 2KV transient with a 14 ohm source. 

[joeqsmith]

A few updates.   I began testing the meters today with enough energy to take out the low current fuses.   Rather than replace expensive fuses, I am no longer testing the current inputs.    However, all of the other modes are still being tested.   If you may recall, early on I talked about removing the fuses during the testing.   As it turned out, this was not a problem until today.   

I am very sorry to say that 2 of the six meters are no longer with us.         The four remaining do not have an easy life ahead of them.    If your favorite company was knocked out of the running, it's not because it was treated unfairly.   For those who are concerned about meters not functioning during the test, these four surviving brands have shown they produce a more robust product.  You may argue that they do not need to but I can tell you, I personally would rather have a meter that does.   

On the generator side of things, I have been clear all along that I am not testing to the IEC standards.   This is a one off generator just to weed things out.   The energy has always been lower than the standard calls for.    I am nearing the end of what I can do with this one.   It was already at lethal levels but these last four I have a feeling are going to require more than I can put out.   But don't worry.  I have plans to build a slightly larger and more lethal version.....   So stay tuned!

If you want a preview of today's testing, enjoy the following short clip:


 

[Meter Junkie]

So, which 2 of the 6 that passed the 2kV testing died?  Will you be hitting the remaining 4 with 3.5kV today?

[joeqsmith]

So, which 2 of the 6 that passed the 2kV testing died?  Will you be hitting the remaining 4 with 3.5kV today?

Just a warning, the results may not be what you're expecting.  I'll have the video up soon.   It will all be in one long video.  Nothing was cut, except for the functional testing at the end.   

Well, we can't make an omelet without breaking a few eggs.   Last night I added about 30% or so more capacity and higher voltage.   The test is set to go.      

[Meter Junkie]

Well, I'm not really hoping for a certain winner, so I don't know what you think I'm expecting. But, based solely on the strength of the brands, I would guess the Extech and Uni-T would be the 2 that didn't make your last test. I expect the Fluke to go the distance.

I am looking forward to see the rest of your testing.  I do surge testing on telecom equipment, but don't test meters for my job. I love blowing stuff up with that machine.  The lab I work in does have a surge generator that can do 12kV through 2 ohms for IEC testing.  My telecom testing does not require me to go that high, so I don't use that machine. But, I'm not going to spend money buying meters just to see how they hold up on that machine.  I guess I'm just not as curious as you. But, I am curious enough to follow this thread, and see which brand holds up the best.

[saturation]

Joe,  continued good job  ,  I watch videos with as much anticipation as Game of Thrones  .  I am away for awhile so can't post for sometime.  Keep up the good work.   

[joeqsmith]

Well, I'm not really hoping for a certain winner, so I don't know what you think I'm expecting. But, based solely on the strength of the brands, I would guess the Extech and Uni-T would be the 2 that didn't make your last test. I expect the Fluke to go the distance.

I am looking forward to see the rest of your testing.  I do surge testing on telecom equipment, but don't test meters for my job. I love blowing stuff up with that machine.  The lab I work in does have a surge generator that can do 12kV through 2 ohms for IEC testing.  My telecom testing does not require me to go that high, so I don't use that machine. But, I'm not going to spend money buying meters just to see how they hold up on that machine.  I guess I'm just not as curious as you. But, I am curious enough to follow this thread, and see which brand holds up the best.

Just a warning, the results may not be what you're expecting.

   

It was more a general statement to the 20 or so people watching the videos.   I think we all have our favorites.  I have been fairly vocal about the Klein Tools meter being the last survivor.   But to be clear, they all get the same abuse.   I am not being paid to run these tests,  no distributors have provided me with free meters nor do I work and have never excepted any payment from any manufactures.   With all the hype, I just wanted to know myself how a small sample would hold up.

I watched several reviews on handheld meters before I started looking to run this little experiment.  Based on what I saw with the UNI-T brand,  I would have thought it would have failed during the first test.   

Really, you specifically should run these tests!   If you can do the 8/20 2 ohm, you are all set.   Think your work would let you rent the lab for 4 days free of charge?   

Joe,  continued good job  ,  I watch videos with as much anticipation as Game of Thrones  .  I am away for awhile so can't post for sometime.  Keep up the good work.   

Thanks.   

If you want to know which ones live and and die, enjoy the following:

[SeanB]

Got a sledge hammer and a large rock to make sure the failures are properly worked over? Failing that a train line, some duct tape and a passing goods train ( plus a high speed camera to catch the squish) works well. A coin on a train line becomes pretty flat afterwards, provided you can actually find it.

[Lightages]

Wow, I am really surprised that the B&K died before the Uni-T.  I look forward to your next pulse machine.

There still seems to be some confusion about whether a meter should survive or just not harm the user. I compiled quotes from different posts in an old thread on CAT ratings. They were excerpts from different parts of the IEC standards but I don't know where this one is from specifically because the IEC documents are not freely available, or at least I have not found them yet. It would be really nice if the IEC would make their publications freely available instead of making people pay for them. It would seem to me to be in the public's best interest to have the information. Hopefully someone with the full standards can clarify this. The part I have states:

101.4  Functional  integrity
After the voltage of  4.4.2.101  has  been applied to the  METER, the  METER  shall continue to be
able to indicate the presence of HAZARDOUS  LIVE  voltages up to the maximum RATED  voltage.

If this is relevant, then any meter you have failed before this video that also has a CATII rating or higher can't be sold in the EU legally. The ones that failed this video with a CATIII rating also cannot. It is my understanding, from watching a video by Martin Lorton at the Fluke facilities, that the US has no restrictions on the legal sale of multimeters, not yet.

There is another part that specifies that any meter should not fail in a way that could harm the user. I wonder how that is actually tested without putting a person in harm's way?

[joeqsmith]

Today's tests went well.   However, I'm sorry to say, I am done for a while.   It has been a solid, three day frenzy with a lack of sleep, food and exorcise.  I managed to run the last set of tests but I am no longer thinking clear and have started to make some mistakes.

What you don't see in these videos is how often I have had the generator apart to rebuild for the next test.   While there is always some risk, this is not something I want to play with when I'm tired.   

Things are only going to continue to get worse for the remaining meters as the source impedance stays fixed at 2 ohms, the time is pushed out to 50uS and the peaks are nearing 4KV.   The attached waveform shows how far things have progressed.   The generator is set for the next tests...  Who will survive???

[Fungus]

In your video, you said you believed that Klein unit could survive higher than a 10 foot drop.  A quick google search returned this.

Those $4 Chinese meters can survive that...

Here's me dropping one:

[Meter Junkie]

Really, you specifically should run these tests!   If you can do the 8/20 2 ohm, you are all set.   Think your work would let you rent the lab for 4 days free of charge?   

There wouldn't be a need to "rent it".  I can have access to it whenever I want.  My point was that I was not going to spend my money ordering out meters to blow up for the fun of it.  I would have fun doing it, but I have other uses for my money.

However, I really appreciate that dedicated people like you have no issue spending money for that kind of fun.

[Meter Junkie]

I have a picture of the beast the day it arrived, but I don't know how to post it on here. It is pretty massive.

[tautech]

I have a picture of the beast the day it arrived, but I don't know how to post it on here.

At the bottom of the page when posting there is a plus sign for attachments, click this and follow your nose. 
Note the restrictions of type and size of files.
I suggest you compress the pics, usually 100K will give plenty of detail.

If you Quote somebodies post, you will see the various formats used to display pics.
Some host pics, others use EEVblog and upload.

[PedroDaGr8]

I have a picture of the beast the day it arrived, but I don't know how to post it on here.

At the bottom of the page when posting there is a plus sign for attachments, click this and follow your nose. 
Note the restrictions of type and size of files.
I suggest you compress the pics, usually 100K will give plenty of detail.

If you Quote somebodies post, you will see the various formats used to display pics.
Some host pics, others use EEVblog and upload.

 I use IMGUR a lot, with an account on IMGUR. Haven't had ANY images deleted and seems to be pretty stable. In fact, looking back over a few older posts from a few years ago. I still used IMGUR without an account and those images have not been deleted either.

[tautech]

Cool, looks like a nasty bit of gear. 

Tip
Place a "Insert image" link in your post, then post, copy the original image's link URL, then edit post placing the URL between the "Insert Image" brackets.

Like this:


Now if you quote this post you can see the syntax used. 

[Meter Junkie]

Maybe I'll stop by Harbor Freight tomorrow, and pick up a $5 meter, and see what this machine will do to that.  I don't mind blowing up a $5 meter.  I just can't justify several $50 meters like Joe.

[joeqsmith]

Really, you specifically should run these tests!   If you can do the 8/20 2 ohm, you are all set.   Think your work would let you rent the lab for 4 days free of charge?   

There wouldn't be a need to "rent it".  I can have access to it whenever I want.  My point was that I was not going to spend my money ordering out meters to blow up for the fun of it.  I would have fun doing it, but I have other uses for my money.

However, I really appreciate that dedicated people like you have no issue spending money for that kind of fun.

That's very nice of them to allow employees access to such equipment for their own use!  Do you have to be trained and have a second person around or can you just run it?   

No problem.  Maybe a few of us can learn something from it, plus have a little fun at the same time.

I've attached a picture of the surge generator.  It is 27 inches high, and 24 deep, and about 17 wide.  The thing weighs over 100 pounds, and can deliver the full 6000 Amps at 12 kV.  If I remember right, it set the lab back about $34,000.

   Notice the slight difference in size!       I was not able to find the correct manual for it.   Is the jumper on the left the 2 ohm and the right 12?   So you add a jumper for the source?   

I do not see where the power feeds into it from the manual or how if connects to the different circuits.  They have a simple schematic and call out the values used.  They do not show the AC at all.   Is it basically just for the telcom industry? 

Ones I am used to can impose the wave on the AC.  L-L L-N L-G ....  It then synchronizes with the AC wave.    I think we can handle a 30A 4-wire circuit with ours and are limited to 300V for the mains.    To test the meters you would need to have the signal ride on the AC.    Imagine the fun!!

If it really is just the waveform,  it still has the potential to do far more damage than my homemade generator.   

[tautech]

Imagine the fun!!

You're