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 1149229 times)

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Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2650 on: July 20, 2018, 10:13:47 pm »
Shame on both of you for taking the time to destroy a man's way of living with blatantly useless reviews...  :-DD

I have some carefully crafted design decisions for you:

It's all so clear now!!  :-DD 



 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2651 on: July 20, 2018, 10:23:09 pm »
I review another Keysight guys channel's speaking in Portañol too..  :-DD (at least that's how it sounds to me..)

The only thing that caught my eye with your posts was their first response where they write "I said "for low voltage home hobby"", yet they demonstrated the meter attached to the mains without a care in the world.   I guess they have never seen a large transient on their lines.    Oh, that's right, the upstream fuses, transformer and lines limit the energy.  That is until your tree gets hit and bypasses the whole mess.   :-DD

Offline Cliff Matthews

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Re: Handheld meter electrical robustness testing.
« Reply #2652 on: July 20, 2018, 11:21:11 pm »
I review another Keysight guys channel's speaking in Portañol too..  :-DD (at least that's how it sounds to me..)

The only thing that caught my eye with your posts was their first response where they write "I said "for low voltage home hobby"", yet they demonstrated the meter attached to the mains without a care in the world.   I guess they have never seen a large transient on their lines.    Oh, that's right, the upstream fuses, transformer and lines limit the energy.  That is until your tree gets hit and bypasses the whole mess.   :-DD
Now who knows about transients like Lightning Joe?
(something tells me by now, you've got hockey-puck size GDT's in your electrical panel..)
 

Offline rsjsouza

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Re: Handheld meter electrical robustness testing.
« Reply #2653 on: July 21, 2018, 12:56:25 am »
Nor me Joe, I review another Keysight guys channel's speaking in Portañol too..  :-DD (at least that's how it sounds to me..)
Who is that, Cliff? I would love to take a look at the video.
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 

Offline bitseeker

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Re: Handheld meter electrical robustness testing.
« Reply #2654 on: July 21, 2018, 01:52:25 am »
Nicely done as usual Joe! :-+  We can forget this one as a newbie best buy.. I'll post a link to his channel and see what he says.
*edit - He may not want to promote it in his "store" anymore. I was thinking about 3 of these as disposables but shipping to Canada doubles the cost, so yeah - I think not. Thanks for a really big sheww..!

I read your post.  Here is a partial list if what I see as the MK01A's shortcomings:

  • Battery can be installed incorrectly.  Even the UT61E has different dimensions in the battery holder for the pos/neg. 
  • There are no captive tabs on the large fuse holder to keep it in place if the meter is dropped.   The case also has nothing in the molding to secure it.   
  • When ramping the 10A current input, the supplied leads failed before the 10A fuse blew.
  • I'm not even sure what to say about the glowing small fuse.  Well, it was a cheap unfilled ceramic body.  The type Fungus does not believe exist.  :-DD
  • Capacitance will not zero out without adding an external capacitor. 
  • Very slow auto ranging for a moderate sized capacitor.   The same for lower value resistors.
  • When in AC mode, selecting frequency will require a zero cross for the meter to read it. 
  • When in AC mode, cases like a a full wave rectified signal that is unfiltered can not be read.   
  • When in AC mode, is the input is and AC waveform with a DC bias, the meter may not display the correct value.  In my setup I show the meter reading between 4 volts and 42 volts.
  • When in DC mode, if the the input is an AC waveform with a DC bias,  the meter will not display the correct value.
  • In frequency mode, the meter appears to be susceptible to 3KHz and will display low battery.
  • With a 180MHz 20dBm signal (roughly 3V), the meter will display more than 50 volts.
  • Why do they put the vias in the rotary switch pads?   
  • The mA lead was not soldered.  There were no signs that the solder had wicked to the terminal. 
  • The stupid little piezo grill starter killed it.  The only meters that are damaged by that are UNI-Ts and the lowest of the low.  If the gun had killed it, I may have been alright with it but no, its the test that hardly does anything.   


Also, I have updated the spreadsheet to include this meter.

Thanks, Joe. You've developed quite the suite of functionality tests. Great job catching several issues that, until your video, I hadn't seen anyone else mention about this DMM.
TEA is the way. | TEA Time channel
 

Offline Fungus

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Re: Handheld meter electrical robustness testing.
« Reply #2655 on: July 21, 2018, 09:03:30 am »
...
  • I'm not even sure what to say about the glowing small fuse.  Well, it was a cheap unfilled ceramic body.  The type Fungus does not believe exist.  :-DD

I believe!  \$\Omega\$
« Last Edit: July 21, 2018, 04:59:00 pm by Fungus »
 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2656 on: July 21, 2018, 03:54:53 pm »
Thanks, Joe. You've developed quite the suite of functionality tests. Great job catching several issues that, until your video, I hadn't seen anyone else mention about this DMM.

The testing has definitely evolved into more of a review compared to just running the one transient test.  The time involved now to look at a good meter can be several days but a side effect is I don't look at too many meters now.         

I responded to people who asked me about running the 121GW that I thought maybe a year after the kick start I would have a look.  That's only what, four months away and it looks like they still have not shipped all of the units and they still have some of the problems that I saw in the preproduction unit.   I assume that this is partly why we have not seen an announcement for a release date.

...
  • I'm not even sure what to say about the glowing small fuse.  Well, it was a cheap unfilled ceramic body.  The type Fungus does not believe exist.  :-DD
I believe!  \$\Omega\$
:-DD :-DD  I couldn't let you sit on the sidelines. 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2657 on: July 21, 2018, 05:43:05 pm »
I havn't seen a post like this in a while.   

Offline MacMeter

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Re: Handheld meter electrical robustness testing.
« Reply #2658 on: July 21, 2018, 06:17:10 pm »
I havn't seen a post like this in a while.

“who in their right mind.....?”

I’ll answer that;

LIGHTNING JOE, that’s who!!!
 

Offline rsjsouza

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Re: Handheld meter electrical robustness testing.
« Reply #2659 on: July 21, 2018, 06:27:28 pm »
Man, that is probably part of the crowd that can only read headlines and does not go past the second paragraph.

That gives me one additional suggestion for a test: connect the meter to the coil pins of a 120VDC relay (or any large inductor) and scratch its leads on a DC source. That could maybe convince this person that a real-world scenario could damage his beloved cheapie.
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2660 on: July 21, 2018, 06:34:03 pm »
When I have seen where people have posted about damaging their meters, I will take the time to ask what happened.  I am really interested if they damaged the front end.  Not that I am trying to embarrass them but to see if there is some new test I should consider.   
 
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Online 2N3055

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Re: Handheld meter electrical robustness testing.
« Reply #2661 on: July 21, 2018, 07:12:03 pm »
I can just picture Joe, standing in front of a struck tree, looking at it for a while. And then, with a mocking smile on his face, he looks up and say quietly:"Challenge accepted ....."  :-DD

Yeah, people don't have a clue. I live in a city, even high voltage distribution is underground, and electric network really does damp things a lot..
But as you go few kilometers off the city centre, it gets waaay more dangerous.. Appliances and electronics go "poooof" all the time.

Regards
Sinisa
 

Offline malagas_on_fire

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Re: Handheld meter electrical robustness testing.
« Reply #2662 on: July 21, 2018, 07:39:30 pm »
The Mertek ended quite soon as many uni-t's, by the ESD. The video was very elaborated and to be honest maybe the expectations were worse, like failing at the rectified 230V on the temperature / mV range.

If are starting and wanna test  some circuits to 230V or 110V use back to back transformers to isolate, reduce the amount of energy from the mains. This transformers can be found from older power bricks |O cell phone , game consoles, cordless phones power which didn't use switched power supplies.

If one can make knowledge flow than it will go from negative to positve , for real
 

Offline HKJ

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Re: Handheld meter electrical robustness testing.
« Reply #2663 on: July 21, 2018, 07:41:07 pm »
That lightning hit was only a minor hit, all the wires stayed in the walls.  >:D
When lightning hits close by stuff like CAT rating do not mean much, you might get a million volts and lots of kA.
 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2664 on: July 21, 2018, 07:56:35 pm »
The Mertek ended quite soon as many uni-t's, by the ESD. The video was very elaborated and to be honest maybe the expectations were worse, like failing at the rectified 230V on the temperature / mV range.

If are starting and wanna test  some circuits to 230V or 110V use back to back transformers to isolate, reduce the amount of energy from the mains. This transformers can be found from older power bricks |O cell phone , game consoles, cordless phones power which didn't use switched power supplies.

It's not even so much that it was damaged by the ESD as it was damaged by the do nothing grill starter ESD.    If you watch the first five minutes or so of this video, you can see how that  grill starter compares with my home made ESD gun and the IEC standards.     

https://youtu.be/Qimtx8z6FUQ


Offline malagas_on_fire

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Re: Handheld meter electrical robustness testing.
« Reply #2665 on: July 21, 2018, 11:12:31 pm »
Hi there.

That gives the clarity of the pulse from the various devices and some sort of levels. I remember this from the uni-t ut-181A , this video that you shared looks like a follow-up . I might be wrong...  Is that what you're ESD gun is replicating towards the IEC regarding EMC, but with lower energy?




The spark at 7:56 of the video reminds me the arc mosquito zapper, but much powerfull, looks like when you get zapped also on your car by static discharge... 



If one can make knowledge flow than it will go from negative to positve , for real
 

Offline bitseeker

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Re: Handheld meter electrical robustness testing.
« Reply #2666 on: July 22, 2018, 12:34:43 am »
I havn't seen a post like this in a while.

I wouldn't be surprised that there are actually many more who think that way. They just don't bother to post.
TEA is the way. | TEA Time channel
 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2667 on: July 22, 2018, 12:54:31 am »
Hi there.

That gives the clarity of the pulse from the various devices and some sort of levels. I remember this from the uni-t ut-181A , this video that you shared looks like a follow-up . I might be wrong...  Is that what you're ESD gun is replicating towards the IEC regarding EMC, but with lower energy?

Yes, it was a follow up to the 181A.   I had enough people send me comments that the grill started was not realistic, so I decided to attempt to follow the IEC waveforms.   Yes it's a little on the weak side still.  I did go back and test every meter I had (that was working and had survived the grill starter) using the new gun.  Every one of them survived. 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2668 on: July 22, 2018, 01:08:19 am »
I havn't seen a post like this in a while.
I wouldn't be surprised that there are actually many more who think that way. They just don't bother to post.
I'm sure you are correct.   

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2669 on: August 15, 2018, 05:33:16 pm »
A few people had asked about running a 189.  Something like this may not be too bad.  It's already dead and fairly cheap.  Then again, if someone needed some parts....


https://www.ebay.com/itm/FLUKE-189-TRUE-RMS-MULTIMETER-WITH-LEADS-AND-BAG-FOR-PARTS-OR-REPAIR/263878907548?hash=item3d7068969c%3Ag%3AhjoAAOSwxnlbcyeV&_pgn=2&_sacat=0&_nkw=189+fluke&_from=R40&rt=nc


Offline retiredcaps

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Re: Handheld meter electrical robustness testing.
« Reply #2670 on: August 15, 2018, 06:59:41 pm »
A few people had asked about running a 189.  It's already dead and fairly cheap.
It will likley go for more than $50 USD, but then I haven't participated in almost 4 years now in Fluke ebay auctions. 

Sharp eyed viewers will see battery leakage? on the terminals and left side screw.  Possible pcb corrosion as well.

Fuses might be blown as well.
« Last Edit: August 15, 2018, 08:53:51 pm by retiredcaps »
 

Offline floobydust

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Re: Handheld meter electrical robustness testing.
« Reply #2671 on: August 15, 2018, 07:13:04 pm »
The (white) corrosion on the battery terminals and nearby screws looks like water ingress. I would say it got dunked.
 

Offline Fungus

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Re: Handheld meter electrical robustness testing.
« Reply #2672 on: August 15, 2018, 07:17:35 pm »
A few people had asked about running a 189.  Something like this may not be too bad.

When you ran the first Fluke 87 it caused an outcry because it wasn't a brand new meter.
 

Offline joeqsmithTopic starter

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Re: Handheld meter electrical robustness testing.
« Reply #2673 on: August 15, 2018, 08:34:52 pm »
Yea, that vintage 87V will be a thorn in the test data forever.  Crazy meter.  I think the outcry was because I was killing a Fluke brand meter and not just any Fluke brand meter, but what is touted as the "golden standard"   :-DD.   Where I actually use that old Fluke 189s, that new 87V just sits in its box with its chattering switch.     

There is no way to run a new 189.  $60, it would be fun to play with.   I've sent more costly meters to their graves.   It may also be fun to cycle the switch on such an old meter.   

Still, this one looks in better mechanical condition than the one my friend had given me.   One of you Fluke 189 fanboys needs to step up and save this meter.   :-DD

Offline rsjsouza

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Re: Handheld meter electrical robustness testing.
« Reply #2674 on: August 15, 2018, 08:42:12 pm »
You know you increased the perceived value of this meter, right?  :-DD
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 


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