Poll

Are you interested in seeing more handheld meters tested?

This testing is pointless! Please STOP damaging these meters!
3 (6.4%)
 Yes, I would like to more meters tested.
44 (93.6%)

Total Members Voted: 47

Author Topic: Handheld meter robustness testing  (Read 637074 times)

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Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3675 on: December 31, 2019, 06:03:17 pm »
Let's not confuse "electrical robustness" with safety. I have yet to see a failure mode on these meters that will hurt the user.

Giving misleading readings is the only safety issue I've seen so far - how difficult would it be to design a meter with a universal HV warning? (AC, AC, DC+AC) Some indicator telling the user if it's safe or not even if the meter can't correctly display the reading.
Good point.

I would hope that after all these years that you would never expect my transient tests to ever cause a meter to fail in such a way that it would hurt a user.  I would also hope by now no one would think this was ever a goal.   

I recently repaired a meter that is UL marked.  You will not find a single MOV in the meter.  It was easily damaged with the rectified 220V waveform.   Yet it has a UL mark.  The meter may very well be safe but it's certainly not what I would consider electrically robust.   

Because my hobbies don't involve any high voltage, high energy sources but I do from time to time work with sources of high voltage and low energy,  I am more interested in the EMC rather than the safety standards.  This TPI with it's very weak front end would not survive my normal use.

*****
Just to note, this company clearly is not concerned if the meter survives.  This is a different stance than what Fluke has stated and demonstrated they take  by having their meters survive.   I have often stated that for safety that I would guess that it is more about the mechanics of the meter and the case of the TPI branded SUMMIT meter appears to be one of the more solid ones I have looked at.

The fact that UL would certify the meter leads me to believe that it is not required that a meter survive.   Seeing the Gossen with it's latching relays that can easily change state and cause the meter to not display a hazardous voltage and the 121GW where it seems the firmware can also cause the meter not to display a hazardous voltage,  maybe this is also not a requirement as both of these meters are also certified.   
« Last Edit: December 31, 2019, 06:11:45 pm by joeqsmith »
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Offline Cliff Matthews

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Re: Handheld meter electrical robustness testing.
« Reply #3676 on: January 01, 2020, 04:57:32 am »
With 2 minutes left in the decade.. Happy New Year Joe! and everyone else!
 
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Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3677 on: January 06, 2020, 12:51:26 pm »
Happy New Year!   Hoping Australia's fires are under control soon.   
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 
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Online rsjsouza

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Re: Handheld meter electrical robustness testing.
« Reply #3678 on: January 08, 2020, 08:12:27 pm »
Maybe it has already been discussed before in this thread, but I am wondering why there are no cheap Fluke clones with good electrical robustness. Most of the techniques are in plain sight. Just copy the board with big clearances, large fuses and MOVs. It may cost a few more dollars for parts, but the margin for "professional" multimeters is much larger.

Because:
a) There's no need, sales of unsafe meters are doing just fine.
b) Certification costs money and you're not going to sell many meters without certification marks.
c) Once a meter is certified you're not allowed to change a single component supplier or any part of your production line without going through re-certification.

I suspect (c) is a real problem for Chinese meter makers.
Fungus, "c" is only valid if you apply for their "listed" program (UL, TÜV, Intertek, etc.). The listing requires annual inspection to the manufacturing plant audits and process reviews. Most Chinese low cost meters do not go through that, but that does not solely explain lack of safety: several japanese brands (Samwa, Hioki) have excellent quality and reputation and also do not have markings.

I have been involved with projects where "c" was required but wouldn't think this was required for a DMM.  For example, say your JEDEC 4007 from company X is no longer offered, I doubt you would be required to stop production until you get your new diode certified.   Have anything to back up this statement? 
I don't have anything to back your statement about "production stop due to the lack of certification". This is an exception that would probably be negotiated between the cert agency and the manufacturer. 

My experience with the marking process and audits is related to a few products (not DMMs) we were releasing in the past few years. We didn't fall for the siren songs from the cert agency (ies) as the markings didn't add value to our products, therefore I don't know how the exception would be dealt. 

Happy new year, BTW!
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Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3679 on: January 09, 2020, 03:09:29 am »
Maybe it has already been discussed before in this thread, but I am wondering why there are no cheap Fluke clones with good electrical robustness. Most of the techniques are in plain sight. Just copy the board with big clearances, large fuses and MOVs. It may cost a few more dollars for parts, but the margin for "professional" multimeters is much larger.

Because:
a) There's no need, sales of unsafe meters are doing just fine.
b) Certification costs money and you're not going to sell many meters without certification marks.
c) Once a meter is certified you're not allowed to change a single component supplier or any part of your production line without going through re-certification.

I suspect (c) is a real problem for Chinese meter makers.
Fungus, "c" is only valid if you apply for their "listed" program (UL, TÜV, Intertek, etc.). The listing requires annual inspection to the manufacturing plant audits and process reviews. Most Chinese low cost meters do not go through that, but that does not solely explain lack of safety: several japanese brands (Samwa, Hioki) have excellent quality and reputation and also do not have markings.

I have been involved with projects where "c" was required but wouldn't think this was required for a DMM.  For example, say your JEDEC 4007 from company X is no longer offered, I doubt you would be required to stop production until you get your new diode certified.   Have anything to back up this statement? 
I don't have anything to back your statement about "production stop due to the lack of certification". This is an exception that would probably be negotiated between the cert agency and the manufacturer. 

My experience with the marking process and audits is related to a few products (not DMMs) we were releasing in the past few years. We didn't fall for the siren songs from the cert agency (ies) as the markings didn't add value to our products, therefore I don't know how the exception would be dealt. 

Happy new year, BTW!

I'm a little lost.  Fungus made the statement in regards to meters which I don't believe they would be held to C.  Are you asking under what circumstances we were or just merely pointing out that I did not provide any details?   

I have been involved with getting products certified for safety by UL before but nothing to do with meters.  There was nothing that would have prevented us from changing vendors during production.   

Cases where this may come up is with something a bit more critical.  Something using Rad qualified parts for example.    A story comes to mind from many years ago that made the news.   There was a company making some of the electronics for one of our missiles.  The company wasn't able to purchase some of the MilStd IC's and so they swapped in some commercial parts so they could continue production.  The customer requires the baby papers and so once they received the actual parts, they supplied the accompanied paper work.   They then stored on-site the actual parts.   Someone in the company knew what was happening and what the end product was and contacted the customer.    I want to say that was in the 80's.

****
It seems I saw it on 60 minutes.  Doing a search, I came up with the attached from "Proposed Legislation Regarding Whistleblower Protection: H.R. 2579 ..., Volume 4":   
« Last Edit: January 09, 2020, 04:24:33 am by joeqsmith »
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Online rsjsouza

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Re: Handheld meter electrical robustness testing.
« Reply #3680 on: January 10, 2020, 06:51:46 pm »
I'm a little lost.  Fungus made the statement in regards to meters which I don't believe they would be held to C.  Are you asking under what circumstances we were or just merely pointing out that I did not provide any details? 
I guess the lines were crossed somehow. I was a bit confused and understood that you were asking me to provide documental proof about an assertive I haven't made. Nevermind. It is still early in the year... :P

It seems I saw it on 60 minutes.  Doing a search, I came up with the attached from "Proposed Legislation Regarding Whistleblower Protection: H.R. 2579 ..., Volume 4":
Quite interesting story. The snippet of document you sent has a striking resemblance with the whole 737MAX brouhaha: "Today consultants and private contractors not only build projects, they regulate them."
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Online Fungus

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Re: Handheld meter electrical robustness testing.
« Reply #3681 on: January 10, 2020, 11:59:29 pm »
I'm a little lost.  Fungus made the statement in regards to meters which I don't believe they would be held to C.  Are you asking under what circumstances we were or just merely pointing out that I did not provide any details? 
I guess the lines were crossed somehow. I was a bit confused and understood that you were asking me to provide documental proof about an assertive I haven't made. Nevermind. It is still early in the year... :P

It was me who made it and it was a bit hyperbolic. Joe won't let that pass, not in this thread. :P

You can probably buy a part from a different supplier without losing your certification. Can you use a different (but similar) part? I'm not sure.
« Last Edit: January 11, 2020, 12:02:40 am by Fungus »
 

Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3682 on: January 11, 2020, 12:41:03 am »
The internet is filled with embellishment.  I see no reason to muddy the waters in this thread.  I guess I could try and pump up the performance of the 121GW saying it didn't blow up at 14KV.  True statement, but not helpful in any way.

Quite interesting story. The snippet of document you sent has a striking resemblance with the whole 737MAX brouhaha: "Today consultants and private contractors not only build projects, they regulate them."


Back in 2015 when the internet was in a rage about Volkswagen and their practices, I was thinking what's so news worthy about this.  Yes, history does seem to repeat often...
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline dcac

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Re: Handheld meter electrical robustness testing.
« Reply #3683 on: January 21, 2020, 09:24:15 pm »
I was amazed how fast the 121 seem to react to temperature changes. So here I have taken the green mV trace, flipped it vertically and overlayed on the two temperature traces where red being 121 internal temp and white the chamber temp.
....
Edit: correction! those two screenshots I've merged perhaps wasn't from the same sweep and therefor not in sync to begin with.




Left scale is voltage, right temperature.   White is chamber temp, Red 121's ambient, Green reported voltage.  Samples are roughly at 2Hz and lag is about 170 seconds.  Of course, the time to settle is actually well over an hour in this case..

Thanks for the extra detailed temp sweep.

After some testing it seems much of the drift could be caused by PTC3 and/or PTC4.

On my 121gw especially PTC3 is super sensitive to just lightly touching it with my finger, perhaps raising its temp no more than 3-4C. A 1.000mV reading drops almost directly 50-60uV and when I remove my finger it slowly recovers to 1mV. Touching PTC4 has the same affect but not at all as dramatically and this in fact instead seems to increase the voltage 30uV or so.

Obviously PTC’s are temperature dependent resistance devices but I really could not make any sense of how they manage to affect the reading so much given they only changes about 75 ohms with the same influence from my finger. But one thing that could affect the reading is that these type PTC’s seems to act as true thermocouples too. Measuring the voltage over them with another meter and 121gw turned of, the PTC’s easily generate 50-60uV - again from just slightly heating them with my finger. And this voltage then sits in series with whatever you’re tying to measure with the 121gw.

But it's still unclear how PTC3 can affect mV measurement at all, even if it is generating emf voltages, the main path for mV is through PTC4 and then the triple 300k (R18-20) resistors into PB0 at hy3131 where it is then measured by the ADC. But the PTC3 path ends up in RLD on hy3131 and here it's unclear how this pin is involved in mV mode, according to available documentation, it only seems to connect to the comparator mux in the 3131, the way it's configured by UEi's firmware.

But anyway, if it is the PTC’s causing the drift, at least it can explain why the 121gw reacts so quickly to ambient temperature changes as the PTC's sits very close to the meter casing, and very close to the input jack where the temperature change probably can affect them quite easily.

« Last Edit: January 22, 2020, 12:50:03 am by dcac »
 

Offline EEVblog

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Re: Handheld meter electrical robustness testing.
« Reply #3684 on: February 05, 2020, 06:02:19 am »
 

Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3685 on: February 05, 2020, 06:09:11 pm »
The latest spreadsheet is now available on GoogleDocs here:
https://docs.google.com/spreadsheets/d/1cXzYpIoyVm9QJUju4KXqM22CEQZP3_xwWvDyeVwxTy4/edit?usp=sharing


This spreadsheet seems out of date?

It's on-line now if you would like a copy.     
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 
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Offline MBY

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Re: Handheld meter electrical robustness testing.
« Reply #3686 on: May 21, 2020, 04:12:08 am »
A bit late, but I can say, every Meterman PM55 or Amprobe PM55A I have has failed.

What happens:
- Auto mode freaks out and doesn't work (a short shows an unstable high resistance for example)
- Short detect mode shows shorted
- EF (power stick) mode works
- I can't remember what Low-Z volts does
- Hi-Z voltage works
- Diode mode acts like a short
- High ohms varies from not working to usually sounding the "shorted" beeper; IIRC high ohms will not give a stable reading
- Haven't tested current

What causes this?

The only similar thing I could find was a dying battery.

I purchased a new unit after my PM55A had failed, only to find a PM55 I gave to a friend also failed. I tested a PM55 I had and it too had failed. The replacement? Well, it tested good (testing 5V in auto mode, and shorting probes, that's it...); after a month when I went to use it to test a low voltage DC circuit again, it showed low battery ... and sure enough it failed too.

I'd like to fix them but have no idea where to start or what could have failed.
I'm later still to the game, but I also had problems with the PM55A (and I have mentioned the problems with PM55A on the forum). I own two of them, one bought, one found in a trashcan (no, really!). They are utterly unreliable with constant "restarts" and who can have confidence in a meter that actually have an "reset" procedure printed on the back?

But I may have a "fix". Instead of one CR2032, try two CR2016. It seems almost like the design had two batteries in mind. Of course, this "fix" more than halves the battery life and doubles the battery replacement cost, and 6 volts may still be too much for the design. With two 3 volts button cells, the constant restarts, confusion in auto mode and such disappeared and the meters seems stable. But still, I seldom use them anymore, since I don't really have confidence in them anyway.
 

Offline J-R

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Re: Handheld meter electrical robustness testing.
« Reply #3687 on: May 21, 2020, 05:30:35 am »
I'm later still to the game, but I also had problems with the PM55A (and I have mentioned the problems with PM55A on the forum). I own two of them, one bought, one found in a trashcan (no, really!). They are utterly unreliable with constant "restarts" and who can have confidence in a meter that actually have an "reset" procedure printed on the back?

But I may have a "fix". Instead of one CR2032, try two CR2016. It seems almost like the design had two batteries in mind. Of course, this "fix" more than halves the battery life and doubles the battery replacement cost, and 6 volts may still be too much for the design. With two 3 volts button cells, the constant restarts, confusion in auto mode and such disappeared and the meters seems stable. But still, I seldom use them anymore, since I don't really have confidence in them anyway.

I picked up a dozen of the Amprobe AM-47 last year which is basically the same DMM, although it's possible there are minor internal differences.  $10ea and they were all new old stock, sealed, and of course the batteries were all in various states of discharge.  About half would not power on at all, a few would power on and then reset immediately in Auto mode, and the remaining worked fine for some time before starting to exhibit the classic reset behavior.

Previously I had read about the reset issue so I purposefully left a bunch of them in endless resets for quite some time and did not see any failures.

After ordering a random supply of CR2032 batteries (Sony, Maxell, Energizer), I did determine that it's really hit or miss on these.  Some were almost 3.3V out of the package while others were as low as 3.05V.  I've also seen some that test at a reasonable voltage but then drop with any load.  Even among the name brand manufacturers, many did not have any date codes to properly reference their age.

I kept a few of the DMMs for vehicles, travel bags, various home and work locations, etc.  The rest I gave out to friends and family.

Typical power draw is under 1mA, but during startup in Auto it exceeds 7.5mA, which can trigger the reset on weak batteries.  Powered off it seems to consume around 1uA.

So, I would be curious if you connected yours up to a power supply set for 3V if it would work correctly?  To eliminate any possible battery concern.
 
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Offline GuidoK

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Re: Handheld meter electrical robustness testing.
« Reply #3688 on: July 10, 2020, 11:00:27 pm »
If I might add a suggestion for future models to be tested, I think the Amazon Commercial 90DM610 might be an interesting candidate because of it's price, specs and availability:
https://www.amazon.com/AmazonCommercial-Count-Digital-Multimeter-CATIV/dp/B07W1BL3RH

It's basically a 6k count multimeter with a similar featureset to the brymen bm235, UL listed and iec61010 compliant, but with $49,-- (currently; it's on the rise) it's about half the price of the bm235! (and maybe the cheapest UL listed/IEC61010 multimeter?)
It is a meter made by CEM afaik (DT-9562 rebranded).
I wonder if it would survive the grill igniter test  :-X

The only thing that sets the bm235 apart from this one is the manufacturers' quoted accuracy which is better for the brymen (but this is of course a paper spec, the meter you get could be more accurate)

Kiss Analog already did an interesting review on this meter (well, the previous 90DM600 model but its probably the same):
https://youtu.be/wfFG8v-RPQ8
« Last Edit: July 10, 2020, 11:11:37 pm by GuidoK »
 

Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3689 on: July 11, 2020, 01:13:46 am »
A few people wanted to see one of the newer UNI-Ts as well.   I haven't been giving much thought to testing new meters. 

Dave was posting hints about some new meter he was planning to sell but that seems to have cooled down.  Maybe if it becomes available, I will have a look. 

I watched a few of the Kiss Analog videos on meter safety.  I'll check out the one you linked.

How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 
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Offline GuidoK

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Re: Handheld meter electrical robustness testing.
« Reply #3690 on: July 11, 2020, 01:32:02 am »
Ok looking forward to that. Didn't know UniT had some new meters.
The efford&time you make to test these meters to the extreme is impressive.
And sometimes funny, when you killed that UT181A with just 1 click of the grill starter  :-DD You so much wanted to like that meter, your reaction was priceless  :-DD


In my experience it's pretty quiet in multimeterland especially on top models from the better brands. I suspect that most large brands are working on really intergrating logging/data processing, communications and maybe touchscreen etc (for instance, the fluke 289 has been 12 years on the market or so?, brymen doesnt have a real top model logging meter etc etc).
Dave's 121gw is I think one of the latest 'higher end' meters. And I think gossen replaced the series that you tested (the 300k count one), but with a similar capable model. Maybe/hopefully one without the multiple faults you've discovered  ;)
 

Offline EEVblog

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Re: Handheld meter electrical robustness testing.
« Reply #3691 on: July 11, 2020, 03:13:55 am »
Dave was posting hints about some new meter he was planning to sell but that seems to have cooled down.

The usual delays.
Just got an email that it will be going into UL testing very shortly and they want me to report any issue now (was supposed to have been through UL before, I guess it didn't, or they changed it for whatever reason).
 
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Re: Handheld meter electrical robustness testing.
« Reply #3692 on: July 11, 2020, 03:45:22 am »
Dave was posting hints about some new meter he was planning to sell but that seems to have cooled down.

The usual delays.
Just got an email that it will be going into UL testing very shortly and they want me to report any issue now (was supposed to have been through UL before, I guess it didn't, or they changed it for whatever reason).
Are you brave enough to send one to Joe ?
Avid Rabid Hobbyist
 

Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3693 on: July 11, 2020, 01:45:18 pm »
Dave was posting hints about some new meter he was planning to sell but that seems to have cooled down.

The usual delays.
Just got an email that it will be going into UL testing very shortly and they want me to report any issue now (was supposed to have been through UL before, I guess it didn't, or they changed it for whatever reason).
Are you brave enough to send one to Joe ?
I don't have a problem paying for it like everyone else and would rather wait until it has been vented and is available to the general public.   
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3694 on: July 11, 2020, 02:28:21 pm »
Ok looking forward to that. Didn't know UniT had some new meters.
The efford&time you make to test these meters to the extreme is impressive.
And sometimes funny, when you killed that UT181A with just 1 click of the grill starter  :-DD You so much wanted to like that meter, your reaction was priceless  :-DD


In my experience it's pretty quiet in multimeterland especially on top models from the better brands. I suspect that most large brands are working on really intergrating logging/data processing, communications and maybe touchscreen etc (for instance, the fluke 289 has been 12 years on the market or so?, brymen doesnt have a real top model logging meter etc etc).
Dave's 121gw is I think one of the latest 'higher end' meters. And I think gossen replaced the series that you tested (the 300k count one), but with a similar capable model. Maybe/hopefully one without the multiple faults you've discovered  ;)

Honestly, when I started watching Dave's videos, it was because of the pure entertainment of seeing him review meters.  There are so many people reviewing them now that I don't find entertaining and they lack the technical knowledge to be a good presenter.   

The KISS Analog guy seems to be doing a bit with SPICE and trying to teach some basics.  I would say he is doing a much better job than I did with my early videos.  I watched the review you linked but I didn't get much out of it.   

Look at all the protection your getting for your money..   

Protection for the meter?  Protection for the user?  The only way to know if the meter is more robust than others is to compare it.   Dave's 121GW for example uses PTCs for the loading.  We wouldn't say they are there for protection.   I suspect the Amazon CEM has a similar input as the higher end CEMs I have.  They don't take the typical 3XMOV, 2XPTC approach for what ever reason but as we have seen, more PTCs / MOVs doesn't mean more robust. 

Recently I posted having a UL cert and doesn't mean the meter is robust and I would say having a cert does not mean that the meter is safe as we saw with the problems with the 121GW and the Gossen Ultra.   
       
https://www.eevblog.com/forum/testgear/hear-kitty-kitty-kitty-nope-not-that-kind-of-cat/msg2851814/#msg2851814
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 
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Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3695 on: July 11, 2020, 07:53:28 pm »
Kiss Analog already did an interesting review on this meter (well, the previous 90DM600 model but its probably the same):

It appears the 90DM600(DT-9560) costs $86.18 and the 90DM610 (DT-9561) is $49.00.     
I have not checked CEM to see what the differences were.   I would not expect them to behave the same when tested.   
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline GuidoK

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Re: Handheld meter electrical robustness testing.
« Reply #3696 on: July 11, 2020, 09:36:17 pm »

It appears the 90DM600(DT-9560) costs $86.18 and the 90DM610 (DT-9561) is $49.00.     
I have not checked CEM to see what the differences were.   I would not expect them to behave the same when tested.

It was speculated that the  90DM600 is phased out in favor of the 90DM610 and therefore prices are maybe rising? (don't know what clever algorithm comes up with those prices).
But take note, the DT-9560 and DT-9561 are NOT CEM designations.
CEM has a  DT-9560 and DT-9561, but lists them as 4k count meters, whereas both 90DM600 and 90DM610 clearly are 6k counts.
So either CEM lists them wrongly, or DT-9560 and DT-9561 in amazon's designation 90DM600(DT-9560) and 90DM610 (DT-9561) are different.

Listing at CEM, where DT-9560 and DT-9561 are both 4k count meters and only the DT-9562 is a 6k count meter:
http://www.cem-instruments.com/en/Product/detail/id/1434

Whether 90DM600 and 90DM610  are the same I don't know. Opening them up can only provide the answer ;).
I think specs and functionality from the manual are the same I believe for what I've seen.
« Last Edit: July 11, 2020, 09:39:46 pm by GuidoK »
 

Offline joeqsmith

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Re: Handheld meter electrical robustness testing.
« Reply #3697 on: July 11, 2020, 10:22:41 pm »
Are you buying the 610 to compare them?   

They look like CEM products. 
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline GuidoK

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Re: Handheld meter electrical robustness testing.
« Reply #3698 on: July 12, 2020, 12:01:24 am »
No I don't really have the need for another 6k count meter as I already have several.
Also I live in europe, so there is at least a ~$30 charge for transport and taxes for the amazon meter, so it would come very close to the price of a bm235 (BM235 is here about ~€85).
Then the price difference becomes pretty low and the bm235 is of course a meter that has proven itself so for europeans that might be the better deal (or one of the higher brymens, they are priced pretty well here).
I think this meter is mainly a potential good deal for US based buyers on a tight budget, maybe young hobbyists that are starting with their electronics hobby (I can't see US shipping costs, but I presume it can come delivered free of charge with amazon prime or so).
I was mainly amaized at the US retail price for a UL listed/iec61010 compliant DMM (apart from whether these specs add something to the meter or not).
Normally for that price you sometimes don't even get ceramic sand filled fuses.

« Last Edit: July 12, 2020, 12:09:55 am by GuidoK »
 

Offline joeqsmith

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  • Country: us
Re: Handheld meter electrical robustness testing.
« Reply #3699 on: July 12, 2020, 12:46:54 am »
No I don't really have the need for another 6k count meter as I already have several.
Also I live in europe, so there is at least a ~$30 charge for transport and taxes for the amazon meter, so it would come very close to the price of a bm235 (BM235 is here about ~€85).
Then the price difference becomes pretty low and the bm235 is of course a meter that has proven itself so for europeans that might be the better deal (or one of the higher brymens, they are priced pretty well here).
I think this meter is mainly a potential good deal for US based buyers on a tight budget, maybe young hobbyists that are starting with their electronics hobby (I can't see US shipping costs, but I presume it can come delivered free of charge with amazon prime or so).
I was mainly amaized at the US retail price for a UL listed/iec61010 compliant DMM (apart from whether these specs add something to the meter or not).
Normally for that price you sometimes don't even get ceramic sand filled fuses.

Is the DT-9561 UL listed?  I was looking on the Amazon ad and in the manual they link and did not see where it was certified.  The manual claims it meets UL... but there is no report number.   Looking at the higher priced meter, I don't see a report number.     Their pictures are not clear enough to see a UL mark.
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 


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