Handheld meter robustness testing

[kalel]

Speaking of continuity, as I never owned an "expensive" (I know that's relative to people and purpose) meter myself, how do the DT830's stack up with the higher quality meters?

You mean the freebies? They measure OK but they're liable to fail at any moment and I wouldn't put them within 10 yards of a mains socket.



Do they even have a continuity test? Mine doesn't.

Somewhere they seem to be freebies, although they are the cheapest available beside that one analog meter - cost $3 or so from China ($4 for the temp measurement model 838 that comes with thermocouple). I think that 830D should have a shared diode/continuity beep test.



I did see that video too, you have to be careful with selecting ranges, not just with mains, and not just with this meter. The probes fail most often, and the sockets can fail.

P.S. This manual http://all-sun.com/manual/Dt830_en.pdf (I'm not sure if anyone ships that manual, just a result of a search for the models) says:

SAFETY INFORMATION
DT830 series multimeter have been designed according to IEC-1010
concerning electronic measuring instruments with a measurement category
(CAT 600V), the max. permitted transient voltage: 2500V, and pollution2.

CAT I-Measurement Category I is for measurements performed on
circuits not directly connected to mains. ( Examples are measurements
on circuits not derived from mains, and specially protected (internal)
MAINS-derived circuits. In the latter case, the transient stresses are
variable; for that reason, its necessary that the transient-withstand
-capability of equipment is made known to the user.).
Don’t use the equipment for measurement within
Measurement Categories II,III and IV.

[EEVblog]

Just for kicks I hooked my 121GW up to my 5kV insulation tester yesterday and it survived.
I might do some more testing to see if this can kill other meters.
Don't have a 5kV scope probe to see the waveform though, but assume there will be a small initial energy burst and then clamping down.

[Fungus]

I did see that video too, you have to be careful with selecting ranges, not just with mains, and not just with this meter.

I don't think you watched it very carefully.

Right after the DT830 exploded he picked up a Fluke which was connected to the same power supply and held it in his hand while moving the range selector to all positions.

P.S. This manual http://all-sun.com/manual/Dt830_en.pdf (I'm not sure if anyone ships that manual, just a result of a search for the models) says:

SAFETY INFORMATION
DT830 series multimeter have been designed according to IEC-1010
concerning electronic measuring instruments with a measurement category
(CAT 600V), the max. permitted transient voltage: 2500V, and pollution2.

The IEC-1010 standard says that the meter must be safe at the maximum rated voltage with the selector in any position.

Any meter where "you have to be careful with selecting ranges" automatically fails that standard.

(ie. They're lying about the DT830 safety rating)

[kalel]

I did see that video too, you have to be careful with selecting ranges, not just with mains, and not just with this meter.

I don't think you watched it very carefully.

Right after the DT830 exploded he picked up a Fluke which was connected to the same power supply and held it in his hand while moving the range selector to all positions.

I meant that this isn't the only meter where you should take care to use the correct range.

The IEC-1010 standard says that the meter must be safe at the maximum rated voltage with the selector in any position.

Any meter where "you have to be careful with selecting ranges" automatically fails that standard.

(ie. They're lying about the DT830 safety rating)

Not a great surprise, I couldn't find after a simple search the important parts of IEC-1010, so I wouldn't know anything about the standard itself. 

[Fungus]

Not a great surprise, I couldn't find after a simple search the important parts of IEC-1010, so I wouldn't know anything about the standard itself.

You have to pay to read it.

[stj]

I don't think you watched it very carefully.

Right after the DT830 exploded he picked up a Fluke which was connected to the same power supply and held it in his hand while moving the range selector to all positions.

natural selection may catch up with him one day.
something i'v been wondering, the standard may well say that the meter must be safe in any range/setting, but nothing about changing settings on the fly.
are the switch contacts in meters make-before-break, or break-before-make?
and what type of gap is there as the switch is rotated?

it may look clever spinning the dial with the power connected - but it's not really - it's dumb.
it's like constantly running across the street, just because your a fast runner.
sooner or later you wont be doing it again!

[joeqsmith]

Just for kicks I hooked my 121GW up to my 5kV insulation tester yesterday and it survived.
I might do some more testing to see if this can kill other meters.
Don't have a 5kV scope probe to see the waveform though, but assume there will be a small initial energy burst and then clamping down.

Hard to say much about the post.  You may have had the meter connected and in the off position for all I know.  Maybe the insulation tester was off or set to 500V.   Let's assume you actually programmed the insulation tester for 5KV and you connected between the 121GW's  V & Com inputs and checked it with the meter set to every mode and it survived.  I still have no idea what insulation tester was used.   Looking at the Hioki 3455  it looks like it has a short circuit current of 2mA or less.  It may be enough to damage the meter but I would expect the 121GW's front end to clamp that down easily, maybe. 


Added.  You are aware I had changed out the HFE part.  This is one of the weak points of the design.  If you wanted to try it with the meter set to Hz with the insulation tester putting out a positive voltage on  V/Ohm relative to GND, it may do something.  You need to somehow get the insulation tester to put out the voltage with an open, get the 5KV then discharge it across the meter.  The capacitor that AC couples the grounds together may be enough to exceed the HFE's absolute maximum supply voltage.   

A member here, Scott was playing around with electronic fly swatters and actually damaged a meter with one.   TI bought one and tried to damage the UT90A with it.  The UNI-T UT90A has had more abuse and damaged more times than any meter I have.   They flyswatter did not have enough energy to get the job done.  The UT90A's clamp would just load it down.  So I added a little external capacitance, let it charge, then discharged that into the meter.  None of this is useful data and it's not something that is recorded in my spreadsheet.     

[joeqsmith]

Saw Dave post this in the 121GW thread.  The thing that caught my attention is the Gossen Ultra Bluetooth meter.  I was aware he had the Energy and another one but this is news to me.  I wonder if Gossen supplied it as part of damage control hoping for a debunk video.     

Personally, I would welcome seeing Dave make such a video debunking my findings with this meter.  Even just the shorted inputs, statically charged foam block and magnetic strap test with a quick pop the cover to show it looks the same as mine.   If it behaves any differently, it would be good to try and understand why. 

I have not heard any more from Gossen after they made the statement about assigning resources to look into my findings and doing a risk assessment.  Maybe a quick marketing debunk video was the best idea they could come up with?    Run it!

FYI:

[evava]

Joe, according to picture I was also looking forward to temperature stability test of your new Fluke 189, do you plan to run it some time later?

And, if I may ask, could you also test $19 AN8008, when you have it?
I hope this to be better than Gossen and... 

[EEVblog]

I should have ran my test at 10V and then looked at the mV as a percent change and really make those numbers look good.  But instead, I ran the same test as before.  1mV, highest sensitivity range, -20 to 60C then calculate a TC from that by looking at the change in voltage / change in temp. 

Want to know how the pre-production 121GW and Gossen M248B compare against my most stable meter, watch and find out. 

Joe, this test is completely invalid. The meter you have is not the current pre-production unit, it's a prototype that does not have the current voltage reference or divider resistors. I mentioned this in the emails to you when I sent it, so I'm not sure why you tested this.
It is most definitely not representative of the final unit.
I'd appreciate if you don't do any more further testing on this unit as it will only confuse people.
Thanks.

[pmcouto]

No worries, Dave.

For all people following 121GW development progress it’s crystal clear that this meter is a pre-production unit, not representative of final product. We all know that final production units will have several improvements, namely better tempco voltage reference and divider resistors.

Joe’s test shows that pre-production 121GW is already one of best tested meters, beating the much higher priced Gossen. Final production units, with improved Vref and divider resistors, will surely be even better! 

[joeqsmith]

Joe, according to picture I was also looking forward to temperature stability test of your new Fluke 189, do you plan to run it some time later?

And, if I may ask, could you also test $19 AN8008, when you have it?
I hope this to be better than Gossen and... 

I doubt I will do anything with the 189.  If I could buy a brand new one, I would have no problems running it through all of the tests.

For the AN8008, you want to know how temperature stable it is?   

That Gossen has been a disappointment on so many levels.  Maybe the M248B Dave has is the pinnacle of meters.  Using the data he collected, with a delta of 31.9C and 500uV spread, it's still 15.7uV/degC.  Way higher than any meter I have looked at to date.  The only worse meter I looked at was the TPI 194II and that's because the thing could not handle cold temps.   

[3db]

@eevblog
I think Joe stated in the video that is wasn't the final production unit anyway.

[joeqsmith]

In order to avoid further confusion about the up and coming 121GW, I have removed all but the original video.  It seems having pre-production in the title and mentioning that throughout the videos and then explaining that I had even modified it, still did not mean that everyone would understand that this was not a production unit.   I assume Dave reviewed the original video of the set and gave me the thumbs up to make it public, so I plan to leave that one.   

I made an attempt to remove some of my posts detailing my findings with the 121GW as well.  I had made measurements of settling times and such for the meter which like the videos could be a source of confusion as well.   Obviously, I can't remove everything without everyone's help removing their own comments but it should help.

I am still looking forward to doing a full on review of the released meter. At that stage I will have the same meter everyone else does.  So stay tuned for that..

Also, you may have noticed that I did some additional house cleaning.  When I was looking at YT,  I was tagged several times over copyrights.  I had a video I took at the dragstrip of a friend of mind on a really old Triumph dragbike he built.   The track had music playing over the loud speaker.  Even though, it was only part of the song and it was buried by the noise, it was flagged and the audio was stripped so you could no longer hear the bikes motor.  Really sad we have come to this.   On the plus side, I don't think there was anything of great loss.  I had one video where I had worked with a guy in Australia comparing some free FEA tools with a high end product and we then modeled my one motorcycle's chassis.  We then modified the chassis to match the model.   It was the first time I ever ran a 1/4 mile in under 8 seconds.   I don't just play with meters..

[kalel]

I also think it would be interesting to see the AN8008's temperature stability.
And if you do get around to testing it, maybe it could be compared with AN8002?

[EEVblog]

That Gossen has been a disappointment on so many levels.  Maybe the M248B Dave has is the pinnacle of meters.

I think mine is one of the first units, I've had it for a long time and I think they sent it when it was released.

[rsjsouza]

In order to avoid further confusion about the up and coming 121GW, I have removed all but the original video.  It seems having pre-production in the title and mentioning that throughout the videos and then explaining that I had even modified it, still did not mean that everyone would understand that this was not a production unit.   I assume Dave reviewed the original video of the set and gave me the thumbs up to make it public, so I plan to leave that one.   

I made an attempt to remove some of my posts detailing my findings with the 121GW as well.  I had made measurements of settling times and such for the meter which like the videos could be a source of confusion as well.   Obviously, I can't remove everything without everyone's help removing their own comments but it should help.

I am still looking forward to doing a full on review of the released meter. At that stage I will have the same meter everyone else does.  So stay tuned for that..

Also, you may have noticed that I did some additional house cleaning.  When I was looking at YT,  I was tagged several times over copyrights.  I had a video I took at the dragstrip of a friend of mind on a really old Triumph dragbike he built.   The track had music playing over the loud speaker.  Even though, it was only part of the song and it was buried by the noise, it was flagged and the audio was stripped so you could no longer hear the bikes motor.  Really sad we have come to this.   On the plus side, I don't think there was anything of great loss.  I had one video where I had worked with a guy in Australia comparing some free FEA tools with a high end product and we then modeled my one motorcycle's chassis.  We then modified the chassis to match the model.   It was the first time I ever ran a 1/4 mile in under 8 seconds.   I don't just play with meters..

In times like these, just be sure you won't be sued for libel by Fluke and Gossen due to your 87-V and MetraHit results...

[deflicted]

In order to avoid further confusion about the up and coming 121GW, I have removed all but the original video.  It seems having pre-production in the title and mentioning that throughout the videos and then explaining that I had even modified it, still did not mean that everyone would understand that this was not a production unit.   I assume Dave reviewed the original video of the set and gave me the thumbs up to make it public, so I plan to leave that one.   

I made an attempt to remove some of my posts detailing my findings with the 121GW as well.  I had made measurements of settling times and such for the meter which like the videos could be a source of confusion as well.   Obviously, I can't remove everything without everyone's help removing their own comments but it should help.

I am still looking forward to doing a full on review of the released meter. At that stage I will have the same meter everyone else does.  So stay tuned for that..

Also, you may have noticed that I did some additional house cleaning.  When I was looking at YT,  I was tagged several times over copyrights.  I had a video I took at the dragstrip of a friend of mind on a really old Triumph dragbike he built.   The track had music playing over the loud speaker.  Even though, it was only part of the song and it was buried by the noise, it was flagged and the audio was stripped so you could no longer hear the bikes motor.  Really sad we have come to this.   On the plus side, I don't think there was anything of great loss.  I had one video where I had worked with a guy in Australia comparing some free FEA tools with a high end product and we then modeled my one motorcycle's chassis.  We then modified the chassis to match the model.   It was the first time I ever ran a 1/4 mile in under 8 seconds.   I don't just play with meters..

In times like these, just be sure you won't be sued for libel by Fluke and Gossen due to your 87-V and MetraHit results...

How is it that a video from a drag strip is flagged because there happened to be some music playing in the background, and yet there are still thousands of full albums you can listen to on YT just by Googling "<album name> full album"? Is that only true for artists who've decided that the "exposure" they get from being available on YT is a net win? Or is it just that the people uploading these videos put a new one up as soon as the old one gets taken down, forcing copyright owners to play whack-a-mole? Granted, I don't recall seeing a whole lot of Top 40 stuff available as full albums on YT, but plenty of fairly well-known bands nonetheless.

[joeqsmith]

In times like these, just be sure you won't be sued for libel by Fluke and Gossen due to your 87-V and MetraHit results...

I could see them going for YT first and having them close my account.  I'm not sure on what grounds other than they don't like the results.  It would be better if they spent the resources on making a better product it the goal is to do better in my tests.  I can't see screwing the results for anyone.

Had some idiot post a comment in the last video, something to the effect of me burning all my bridges and something about Dave not helping me out in the future.  I would guess I had more than 60 hours into the 121GW videos, tracking down parts, repairs, mods and such.  I don't charge anything for these videos.  I have no intentions to ever turn on ads.  I don't even have a patron or ask for money.  It's done out of pure interest on my part.  In the end, pulling the videos was the right thing to do if it really was causing confusion. 

Retrospect, I could have ran the meter to the point of not being able to repair it but I would hope that some of the information I provided Dave would help them come up with a better product. 

So to the idiot who posted that comment, let me make it clear, I could care less about burning bridges or who sends me what.  In the end, it costs me time and money.  I will continue to run the tests unbiased, collect the data and present it.  If you don't like the results, don't watch.

[joeqsmith]

How is it that a video from a drag strip is flagged because there happened to be some music playing in the background, and yet there are still thousands of full albums you can listen to on YT just by Googling "<album name> full album"? Is that only true for artists who've decided that the "exposure" they get from being available on YT is a net win? Or is it just that the people uploading these videos put a new one up as soon as the old one gets taken down, forcing copyright owners to play whack-a-mole? Granted, I don't recall seeing a whole lot of Top 40 stuff available as full albums on YT, but plenty of fairly well-known bands nonetheless.

Its sad to see us reach that level of greed.  I wasn't profiting from these videos and I doubt that any were audio tracks people would rip.  In the case of my friends antique dragbike, I could not strip the music.  All I can do is remove the video or leave it without sound.   Personally, I don't mind sharing some of what I do on YT but at the same time I have wasted a fair amount of time putting the videos up only to pull them down again.   May need to rethink this whole YT thing.  Getting too old to waste too much time.

[IanB]

Its sad to see us reach that level of greed.  I wasn't profiting from these videos and I doubt that any were audio tracks people would rip.  In the case of my friends antique dragbike, I could not strip the music.  All I can do is remove the video or leave it without sound.   Personally, I don't mind sharing some of what I do on YT but at the same time I have wasted a fair amount of time putting the videos up only to pull them down again.   May need to rethink this whole YT thing.  Getting too old to waste too much time.

I don't think YouTube is the place for video sharing any more. It's too commercialized and too unfriendly to individual content creators. Maybe better to consider Vimeo or Daily Motion?

[kalel]

Its sad to see us reach that level of greed.  I wasn't profiting from these videos and I doubt that any were audio tracks people would rip.  In the case of my friends antique dragbike, I could not strip the music.  All I can do is remove the video or leave it without sound.   Personally, I don't mind sharing some of what I do on YT but at the same time I have wasted a fair amount of time putting the videos up only to pull them down again.   May need to rethink this whole YT thing.  Getting too old to waste too much time.

I don't think YouTube is the place for video sharing any more. It's too commercialized and too unfriendly to individual content creators. Maybe better to consider Vimeo or Daily Motion?

In case of specialized/niche videos like these, if you make videos on those websites, would less people find them, or would it be similar?

Anyway, I'm sure it can take a lot of time and effort to run the informative tests. Thanks for doing them.

[joeqsmith]

...
And, if I may ask, could you also test $19 AN8008, when you have it?
I hope this to be better than Gossen and... 

I also think it would be interesting to see the AN8008's temperature stability.
And if you do get around to testing it, maybe it could be compared with AN8002?

All the meters I have looked at have drifted less than 2mV over that 80 deg C span.  Even the CEM and the UT61E were less than 600uV.  I am not sure why that Gossen was so bad.  Dave shows 500uV for a 31.9 degree change.  That's really bad from what I have seen.  Maybe I just received exceptional meters.   
 
Once I have the meters I can do some sort of comparison of the two.  Fungus was asking about the ESD so that was really my only plans for it. 

[rsjsouza]

In times like these, just be sure you won't be sued for libel by Fluke and Gossen due to your 87-V and MetraHit results...

I could see them going for YT first and having them close my account.  I'm not sure on what grounds other than they don't like the results.  It would be better if they spent the resources on making a better product it the goal is to do better in my tests.  I can't see screwing the results for anyone.

YT is mostly concerned with media companies, thus the problem with the background music. However, it is not hard to believe this is always a possibility with absolutely everything posted on their platform. They do not really answer to any reason when a takedown notice is sent - they shoot first and ask your name later. IIRC Dave discussed this, as well as many other bloggers as the one below:


 

Had some idiot post a comment in the last video, something to the effect of me burning all my bridges and something about Dave not helping me out in the future.  I would guess I had more than 60 hours into the 121GW videos, tracking down parts, repairs, mods and such.  I don't charge anything for these videos.  I have no intentions to ever turn on ads.  I don't even have a patron or ask for money.  It's done out of pure interest on my part.  In the end, pulling the videos was the right thing to do if it really was causing confusion. 

Retrospect, I could have ran the meter to the point of not being able to repair it but I would hope that some of the information I provided Dave would help them come up with a better product. 

So to the idiot who posted that comment, let me make it clear, I could care less about burning bridges or who sends me what.  In the end, it costs me time and money.  I will continue to run the tests unbiased, collect the data and present it.  If you don't like the results, don't watch.

Agreed wholeheartedly. The fanboys do not pay your bills nor help you. Of all technical folks around, I suspect that Dave would be the one that would mind the least having a fair and unbalanced review of his product. He knows nothing is perfect and, to actually put a product out of the door, you have to compromise somewhere; that or you never release anything.

Its sad to see us reach that level of greed.  I wasn't profiting from these videos and I doubt that any were audio tracks people would rip.  In the case of my friends antique dragbike, I could not strip the music.  All I can do is remove the video or leave it without sound.   Personally, I don't mind sharing some of what I do on YT but at the same time I have wasted a fair amount of time putting the videos up only to pull them down again.   May need to rethink this whole YT thing.  Getting too old to waste too much time.

I don't think YouTube is the place for video sharing any more. It's too commercialized and too unfriendly to individual content creators. Maybe better to consider Vimeo or Daily Motion?

Despite one issue here and there, I don't think YT is that bad. Also, the fact they give the space free for people with excellent content but not much traffic is an incredible feat.

[kalel]

Regarding robustness, now that I am waiting for a rebranded an860b+ and this video is more important for me than before:

(I don't remember details so I am watching it again, although it will take a bit).

I wonder, does the larger PCB comparing to the small version make a difference? There's more space, but I don't know if it does provide better clearances.