EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: groovesonshunt on January 16, 2023, 06:20:51 pm
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I just got my new Brymen BM789 today, and I am very pleased with the build quality.
The first thing that I did noticed was, that the meter moves a lot when it's on the stand while I use the dial.
Can anyone tell me if your 789 has a rubber ring around the edge of the stand?
Mine came with the 789011 firmware, and when I look at the picture on the .eu website, there seem to be a rubber ring around the edge of the stand.
What about your 789.....does it have a non-slip coating?
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Nothing on mine. I don't see anything in any photos either.
You could probably find a small bit of rubber hose, split it open and attach it to the stand.
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The first thing that I did noticed was, that the meter moves a lot when it's on the stand while I use the dial.
All meters do that. :-//
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Also nothing on mine.
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Nothing on my 786 (same form factor) either.
I use a non-slip anti-static mat on my bench. As such it (nor any other meter) does not move when I use it on the stand.
Don't see anythjing in the picture either. This shot is from Brymen's EU site.
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The first thing that I did noticed was, that the meter moves a lot when it's on the stand while I use the dial.
I think all multimeters do that. :popcorn:
AFAICT the stand is there for the viewing angle, not for using it one-handed.
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I just got my new Brymen BM789 today, and I am very pleased with the build quality. ...
I am not. I got one from Welectron with a crooked amps socket and frayed red insulators. Nevertheless, the leads plug in well and everything is functional.
But no chinese crap I ever got was like that.
Besides this, my BM789 is - related to my AD584 reference, checked with a well calibrated HP 34401A - on the lower side of the 0,03% tolerance. Even 30$ stuff from Amazon is more accurate, not to mention my older (but self calibrated) cheapos.
Nevertheless, it's fine and fast. I love the fast resistor autoranging and the low-Z mode.
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Can you post some photos of the areas in which this is not very accurate?
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I gave it a closer look. It's more on the upper side. And it's well within the specs as expected, no doubt. But it could be better...
Given a AD584 with its test protocol (measured with an Agilent 34401A), and a measurement with an well calibrated HP 34401A (which values are slightly above), I referred to the average of both to calibrate my meters (if possible)
The average values of the 2.5/5/7.4/10V thus are 2,49961, 5,001085, 7,50091 and 10,00183 volts
My Brymen BM789 reads
2,4999 (+0,01%), 5,002 (+0,02%) in the 6V range and
2,500 (+0,02%), 5,003 (+0,04%), 7,503 (+0,03%) and 10,005 (+0,03%). If I had 5.001, 7.501 and 10.002, it would be perfect. :)
I'll watch this... maybe the values will get more accurate with a longer on time and near to 20 °C (it's ~24 °C in my hobby room)
And: Most of my cheapos simply do not have that resolution. So a 2.50, 5.00, 7.50 and 10.00 looks better on the first view, but does not have to.
If I compare the AD584 test protocol to the HP 34401, all deviatons are 0,02% or less.
Brymen to AD584 is again within specs (+0,02% @2.5V, +0,03% @5V (+0,04%) in the 6V range. +0,04% at 10V in 60V range.
Absolutely nothing to blame.
I try not to look at the amps socket and everything will be fine ... :clap:
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I have concerns with taking the average of two 34401A units. Do you have the calibration data for each? One is probably better than the other depending on the input provided. So an average may make things worse.
What about calibration data for the AD584?
Regardless, 3 counts away on this 66,000 count DMM is not an issue that needs to be corrected in my opinion. It is not valid to compare how many counts it is out vs. another DMM that is only 6,000 counts, for example.
Also, I am not sure if it is possible to get this any better since the calibration points appear to be at 0 and +/- 3V for the 6V range.
I tested my BM789 and it was 3.0001V and 6.0002V at 21C. I experimented with the DC calibration but am not sure if it completed. After the +/- 1,000V calibration point, it entered the AC+DC calibration and I did not have the information on what to input so had to exit the calibration. Afterwards it still read the same as before.
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I respect your concerns. To make it more clear:
a) My experience is that even cheapos are shipped almost perfect calibrated (within their limits, but far better than the specs). That's what I expected with the Brymen. Of course it's possible that both devices are wrong and the Brymen is right ...
b) The Agilent meausurements _are_ the calibration data delivered with the AD584.
The HP data I do not know, but I was told it is calibrated regulary.
Taking the pure AD584 calibration data, my BM789 is even a bit worse (but also within the specs) - the HP taken into average makes it better :-)
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I echo J-R's comments. BM789 is pushing the accuracy limit for handheld in this price range, so I consider it to be really good as long as it is within spec for a factory calibration. 60,000 count does not help, had it been a 6000 count meter, you would probably think it is perfect.
You can always send it to Welectron for a separate calibration, but I doubt it will get any better. Most cal labs adjust the meter to be within spec, but not necessarily optimized for the smallest error across the entire range.
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It seems that Brymen BM789 is rebranded as Metrel MD 9055. https://www.metrel.si/en/shop/DMM/digital-multimeters/md-9055.html (https://www.metrel.si/en/shop/DMM/digital-multimeters/md-9055.html)
The picture on website and in the datasheet was probably manipulated... The actual product has 60 000 counts not dual lcd.
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Actual photos of Metrel MD9055 show the real LCD! It is not a dual readout lcd.
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I am wondering about buying a Brymen BM789. But is there a competitive DMM in this price category? Some Appa, UNI-T, CEM, Extech? I need some 40 000-60 000 readouts, LoZ, proper input protection and beepjack.
Keysight and Fluke are too expensive for me.
Edit:
I have a BM829s since 2016 and it is quite OK. I just want one more DMM.
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I am wondering about buying a Brymen BM789. But is there a competitive DMM in this price category?
No.
(well, there's some other Brymens...and the blue EEVBLOG meter which is a Brymen)
Keysight and Fluke are too expensive for me.
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You're not missing much. Brymens are just as good for measuring and reliability. Flukes are only worth it if other people are going to judge you by the meter you carry.
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Flukes are only worth it if other people are going to judge you by the meter you carry.
Or if you want to have it calibrated without problems all over the world. Or you really want to use it in a large factory or so.
(There might be some problems with Brymen calibration... )
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You're not missing much. Brymens are just as good for measuring and reliability. Flukes are only worth it if other people are going to judge you by the meter you carry.
https://www.youtube.com/watch?v=3Hlmq57FQQk (https://www.youtube.com/watch?v=3Hlmq57FQQk)
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I am wondering about buying a Brymen BM789. But is there a competitive DMM in this price category?
No. I have not seen another such DMM. Even BM869s I will say No.
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I am wondering about buying a Brymen BM789. But is there a competitive DMM in this price category? Some Appa, UNI-T, CEM, Extech? I need some 40 000-60 000 readouts, LoZ, proper input protection and beepjack.
Keysight and Fluke are too expensive for me.
Edit:
I have a BM829s since 2016 and it is quite OK. I just want one more DMM.
The Flir DM93 has been on sale for $149.99 for a while, seems out of stock currently, not sure if it will be back, maybe keep an eye out. You could check ebay for both the DM93 and the slightly lesser DM92.
Another option is the 121GW.
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Flukes are only worth it if other people are going to judge you by the meter you carry.
Or you really want to use it in a large factory or so.
Isn't that what I said?
(There might be some problems with Brymen calibration... )
Are you talking about calibration or adjustment? A decent lab can calibrate any meter and produce a certificate.
If adjustment is needed on a meter of this class then you should probably regard it as "damaged" and get a new one.
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I am wondering about buying a Brymen BM789. But is there a competitive DMM in this price category?
No. I have not seen another such DMM. Even BM869s I will say No.
BM869s has a higher CAT rating and a longer history.
The BM789 is much newer and has had a few firmware tweaks since introduction (eg. in autoranging). I think the tweaking stage is over now though.
https://www.eevblog.com/forum/testgear/brymen-bm789/msg4349518/#msg4349518 (https://www.eevblog.com/forum/testgear/brymen-bm789/msg4349518/#msg4349518)
To their credit: Brymen was extremely responsive to early testing here on EEVBLOG.
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BM869s has a higher CAT rating
That's of little consequence to most people, especially when you consider the 869 is more designed as a precision high count lab meter than a field test meter. And the 780 series already has 600V CAT-IV which is as a good as it gets from other manufacturers like Fluke for example.
And you pay for that with increased size and weight as well.
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https://www.youtube.com/watch?v=3Hlmq57FQQk (https://www.youtube.com/watch?v=3Hlmq57FQQk)
If you want a more robust meter than the BM789, Brymen does an "industrial" range.
(I know you know this...but not everybody does).
As for the smaller fuse in the Brymen: I'd trade that fuse for input jack alert any day of the week.
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To be clear - there is no North American support for these Brymen multimeters such as repair, calibration, firmware updates? It's gotta be shipped trans-ocean for any of that?
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If you want a more robust meter than the BM789, Brymen does an "industrial" range.
(I know you know this...but not everybody does).
It's always horses for courses.
Some people just want the most features in a price range, which is why Hydrawerk asked for a price range metric.
Some want the best ruggedness and protection.
Some want the best accuracy
etc.
In the case of my video I compared them because Brymen actually produced the 780 series to compete directly with the Fluke 70/170 series. Hence the similar size and feel. But rather than criple it they opted to blow it out of the water feature-wise because they could.
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To be clear - there is no North American support for these Brymen multimeters such as repair, calibration, firmware updates? It's gotta be shipped trans-ocean for any of that?
I've never done it personally but Google comes up with hits for "North America Brymen calibration service". Try phoning one for a quote, see how they respond. Also look for Greenlee calibration services - Brymens are sold under the Greenlee brand over there.
AFAIK Brymen don't do firmware updates.
Repair? I expect my Brymen to out-last me. If it doesn't? I can buy three of them for (eg.) the price of a Fluke so I see no advantage in the famous Fluke warranty. Buying a new one is probably faster than sending it off to a repair service, too. :)
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AFAIK Brymen don't do firmware updates.
Correct. And neither do most dealers AFAIK. Although I will if you are in Australia and want to send it back and pay postage both ways. It's too expensive to send from overseas.
The 780 series is the only Brymen with firmware update capability. I guess they are testing what benefits it has. I don't know if future model meters will have it or not.
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Agree with all the wisdom shared here. The 786/9 is the perfect size, very similar to the Fluke 17X.
I bought the 869S not knowing its actual size, I found it to be a little too large for handheld work. The Fluke 87V is about as large as I would prefer as a handheld meter, the 869S is even larger.
I have all these meters, they all perform excellent. 869S without the auto hold is a disadvantage if you need that feature, which I use occasionally.
I agree with Dave, feature wise, the 78X is absolutely superior to the 17X. But the after sale supports for Fluke is a clear winner if you are in the US.
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I will also add a very long work from 3xAAA Eneloop batteries and 15 min of backlight operation.
It turns out to be very convenient when the BM789 has the ability to work with two thermocouples T1 and T2. You can not pull the probes, but simply connect the thermocouple to free T2 connectors.
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It would be nice if someone who has both Brymen models (78X/86X) could take a couple of pictures (front/side) of them together for size comparison :-+
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AFAIK Brymen don't do firmware updates.
Correct. And neither do most dealers AFAIK.
...
less those who make 121GW :), although there has been no update lately.
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It would be nice if someone who has both Brymen models (78X/86X) could take a couple of pictures (front/side) of them together for size comparison :-+
Also their industrial models, which are much smaller than the 869s. :)
I also wish Brymen would put 3D pictures of their "industrial" meters on the site, too. They look kind of fugly when viewed head on and I think it puts people off owning a nice, low-distraction meter. These meters good on the bench, IMHO, and they're much smaller and slimmer than the 789/869.
It's almost as if Brymen is trying not to sell any. :scared:
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It would be nice if someone who has both Brymen models (78X/86X) could take a couple of pictures (front/side) of them together for size comparison :-+
BM869s is similar to the TPI TPI194, UNI-T UT181A and the Fluke 189. All much smaller than my bench meters and much easier to move around on the bench.
https://youtu.be/pPCtnQa0Thc?list=RDCMUCsK99WXk9VhcghnAauTBsbg&t=979
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All much smaller than my bench meters
"Much"? :-DD
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All much smaller than my bench meters
"Much"? :-DD
Much much!
That vintage Fluke 8506A I saved from scrap must weigh as much as 10 BM869s and at least 5X the size. Even as old as that Fluke is, I don't think you will find a handheld meter that would match it's performance. The only reason I saved it was because of that thermal RMS stage.
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The Fluke has a "2" in a circle molded into the shell on the inside. That would indicate it is a high density polyethylene. HD polyethylene has a density of about .93 at the most. Polycarbonate would ring at about 1.2 so is good bit a tougher. Looks like Fluke did a better job polishing up their molds though. If that is worth anything.
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It would be nice if someone who has both Brymen models (78X/86X) could take a couple of pictures (front/side) of them together for size comparison :-+
Here you go.
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and Fluke 87
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And
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The Fluke has a "2" in a circle molded into the shell on the inside. That would indicate it is a high density polyethylene. HD polyethylene has a density of about .93 at the most. Polycarbonate would ring at about 1.2 so is good bit a tougher. Looks like Fluke did a better job polishing up their molds though. If that is worth anything.
Polycarbonate is much more brittle than polyethylene, which is also highly resistant to acids and solvents.
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It would be nice if someone who has both Brymen models (78X/86X) could take a couple of pictures (front/side) of them together for size comparison :-+
Here you go.
Something is missing from the EEVBLOG lineup.
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Something is missing from the EEVBLOG lineup.
They won't let me sell the 869.
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Something is missing from the EEVBLOG lineup.
They won't let me sell the 869.
The 869s looks fine in red. Where's the 121?
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It's almost as if Brymen is trying not to sell any. :scared:
or don't have so many to sell?
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It's almost as if Brymen is trying not to sell any. :scared:
or don't have so many to sell?
The Brymen web site shows the 850 series as "professional flagship" and their newest meter is an industrial shape.
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So, a short recap of Dave's video:
Brymen wins on:
* Specifications.
* Functions.
* Drift (lower).
* Beefier protection components overall (resistors, varistors).
Fluke wins on:
* Perceived better plastic.
* Perceived better PCB quality.
* Perceived better plating.
* Perceived better Zebra strip connection (although it's display flickers when pressed upon while Brymen don't).
* Bigger fuse.
There are lots of differences. Fluke parts are more integrated, while Brymen has more discrete parts.
Brymen has it's own custom chipset while Fluke has a msp430f437 (USD 10) ltc2435-1 (I think @15:46) costs around USD6) but fluke also has a custom asic.
I am also confused about the voltage divider network.
Fluke is praised for it's famous shine white ceramic, while the covered grey thing of the Brymen is just glanced over and ignored. I'd like to see and know what's under that grey coating, especially since Brymen apparently has better drift specifications.
But overall, quality is quite comparable, and as Fluke is just not affordable for me, I'd buy the Brymen anytime over the Fluke.
Even if it was a birthday present, I'd rather have the Brymen then the Fluke, as I regard it as overpriced and I dislike the idea of rewarding companies for such a policy. Brymen has a much better Performance to price ratio, and that is what I can appreciate.
Also, both DMM's will die if you drive over them with a truck or dip them in molten lava, or they can be unrecoverable if you drop it in a deep pit or a river. Such accidents do happen and when you have to buy a 2nd fluke, for the same price you could have had 4 of such accidents and be on your 5th Brymen for the same price. If you are a service technician out in the field, you may want the most reliable DMM, as a failed DMM can be a multiple hour drive and a wasted day. Or you are prepared and just take out your spare Brymen which was tugged in your car with service equipment...
Also, the split banana jacks are for a function to beep at you when the probe is in the Amp jack while the selector switch is in the volt range. I blew up one of my old (el cheapo) DMM's that did not have this feature, and it has saved me multiple fuses (each EUR10 or so) in the 30 years thereafter. This is an quite important feature for me, and I think the flukes don't have that.
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Polycarbonate is much more brittle than polyethylene, which is also highly resistant to acids and solvents.
LOL!
Calling polycarbonate brittle is like calling copper highly resistive.
Things made with PE:
sandwich bags
freezer bags
vapor barrier
food containers
Fluke meters
Things made with PC:
Bullet proof face shields
motocross goggle lenses
motorcycle helmets
explosion proof cabinets
Brymen meters
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Polycarbonate is much more brittle than polyethylene, which is also highly resistant to acids and solvents.
Calling polycarbonate brittle is like calling copper highly resistive.
Copper is resistive compared to silver. :)
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Polycarbonate is much more brittle than polyethylene, which is also highly resistant to acids and solvents.
Calling polycarbonate brittle is like calling copper highly resistive.
Copper is resistive compared to silver. :)
My point exactly.
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Polycarbonate is also much more brittle then a wet noodle.
And both Diamond and CBN are much more brittle then Polycarbonate.
(And no, that CBN is not Cannabinol, but that other stuff, with Boron in it.)
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Polycarbonate is much more brittle than polyethylene, which is also highly resistant to acids and solvents.
LOL!
Calling polycarbonate brittle is like calling copper highly resistive.
Things made with PE:
sandwich bags
freezer bags
vapor barrier
food containers
Fluke meters
Things made with PC:
Bullet proof face shields
motocross goggle lenses
motorcycle helmets
explosion proof cabinets
Brymen meters
Polycarbonate is also much more brittle then a wet noodle.
And both Diamond and CBN are much more brittle then Polycarbonate.
(And no, that CBN is not Cannabinol, but that other stuff, with Boron in it.)
I note you haven't quibbled about the chemical resistance, and missed off your list of PE uses "bottles for hydrofluoric acid", which I'll grant is a fringe case, so perhaps "fuel can" is more mainstream.
Take a Fluke 87 V and Brymen 869S, chill them down to oh, -10 Celcius or so, then drop them onto concrete from 3m.
I like my 869S, it's in rotation with my Fluke 289 as a mobile bench meter, but at work I use my 87V. The 869 would be too big, and unnecessarily complex. I worry about random processor death with my 869, and supercap issues with my 289. The only thing I worry about with my 87V is theft. I can't say as I've ever worried about the physical robustness of any of them, save perhaps the screen of the 289, but then I'm not particularly accident prone.
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Also, the split banana jacks are for a function to beep at you when the probe is in the Amp jack while the selector switch is in the volt range. I blew up one of my old (el cheapo) DMM's that did not have this feature, and it has saved me multiple fuses (each EUR10 or so) in the 30 years thereafter. This is an quite important feature for me, and I think the flukes don't have that.
The Fluke 87v has that feature (but not every Fluke model does - I'm pretty sure the same is true for Brymen)
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Brymen copied the AutoHold feature from Fluke and the BM78x are the only ones with it.
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I'm pretty sure the same is true for Brymen)
Brymen calls it "Beep-Jack (tm)", and I checked a bunch of their meters, and they all have it. From the cheapest EUR60 to the top models.
It's such a useful feature and cheap to implement, that it just seems silly to not include it.
I checked:
BM235, BM233, BM231
https://brymen.eu/wp-content/uploads/biall/102173/102173.KARTA_EN..2016-09-30.1.pdf
BM257, BM255, BM252, BM251
https://brymen.eu/wp-content/uploads/biall/102085/102085.KARTA_EN..2022-05-17.2.pdf
BM789, BM785
https://brymen.eu/wp-content/uploads/biall/102222/102222.KARTA_EN..2020-10-26.1.pdf
BM807, BM806, BM805
https://brymen.eu/wp-content/uploads/biall/102027/102027.KARTA_EN..2015-07-21.1.pdf
BM867s, BM869s
https://brymen.eu/wp-content/uploads/biall/102092/102092.INSTRUKCJA_EN..2014-11-04.1.pdf
BM878, BM877, BM876
https://brymen.eu/wp-content/uploads/biall/102133/102133.KARTA_EN..2015-07-09.1.pdf
BM905s, BM906s, BM907S
https://brymen.eu/wp-content/uploads/biall/102114/102114.INSTRUKCJA_EN..2014-11-04.1.pdf
I did not check pocket meters and clamp meters. They don't have it of course because they do not have an Amp input.
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But overall, quality is quite comparable, and as Fluke is just not affordable for me, I'd buy the Brymen anytime over the Fluke.
Even if it was a birthday present, I'd rather have the Brymen then the Fluke, as I regard it as overpriced and I dislike the idea of rewarding companies for such a policy. Brymen has a much better Performance to price ratio, and that is what I can appreciate.
For the few people that haven't seen it:
https://www.youtube.com/watch?v=ay9wFQAW19Y (https://www.youtube.com/watch?v=ay9wFQAW19Y)
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I'd rather have the Brymen then the Fluke, as I regard it as overpriced and I dislike the idea of rewarding companies for such a policy.
Well, it seems you never had a fluke for a long time to work with.
At home I got a BM869s, at work we have tons of fluke meters, mostly 87V, some 187/189 and two 289, 15 or more 117 and 179 models.
We still have a 87 from 1990, it was calibrated over 30yrs every year without any issues.
I let my brymen calibrate in the year I bought it (2020) and it must be re-adjusted to reach it´s own specs...
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Also, the split banana jacks are for a function to beep at you when the probe is in the Amp jack while the selector switch is in the volt range. I blew up one of my old (el cheapo) DMM's that did not have this feature, and it has saved me multiple fuses (each EUR10 or so) in the 30 years thereafter. This is an quite important feature for me, and I think the flukes don't have that.
I wouldn't buy a "serious" meter without it.
The Fluke 87v has that feature (but not every Fluke model does - I'm pretty sure the same is true for Brymen)
All Brymens have it AFAIK.
(apart from their pocket meter)
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Something is missing from the EEVBLOG lineup.
They won't let me sell the 869.
The 869s looks fine in red. Where's the 121?
Here you go.
The 121GW was originally smaller, but I decided to move from AAA to AA batteries and they couldn't keep the same dimensions.
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If you are using the meter handheld all day, don't forget the weight. Beyond just length and width, also consider the height. The following weight are measured with Envelop AAA and Lithium 9V batteries
Fluke 179: 405g, 43mm
Bremen 756: 419g, 51mm
Fluke 87v: 508g, 52mm
Bremen 869s: 627g, 64.5mm
I personally find 869s to be the only model that is too thick, too big, and too heavy for handheld job where you have to hold it for an extended period of time, as it is 55% heavier than the 179. The Fluke 179 is the sweet spot for handheld in my book due to its smaller size and weight, with the 756 being a close second if you need more features.
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I note you haven't quibbled about the chemical resistance, and missed off your list of PE uses "bottles for hydrofluoric acid", which I'll grant is a fringe case, so perhaps "fuel can" is more mainstream.
Take a Fluke 87 V and Brymen 869S, chill them down to oh, -10 Celcius or so, then drop them onto concrete from 3m.
Lots of fringe cases here, but while gasoline might give PC a slightly hard time, it's really not where a typical Brymen get's used. As for -10C, well they make snowmobile helmets, goggles and face shields from PC too.
HDPE is a good material for sure. I'm just not convinced it's as tough as or any better than PC. HDPE is less expensive than PC though so I guess that's why Fluke can make meters that are so budget friendly. :-//
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If you are using the meter handheld all day, don't forget the weight. Beyond just length and width, also consider the height. The following weight are measured with Envelop AAA and Lithium 9V batteries
Fluke 179: 405g, 43mm
Bremen 756: 419g, 51mm
Fluke 87v: 508g, 52mm
Bremen 869s: 627g, 64.5mm
I personally find 869s to be the only model that is too thick, too big, and too heavy for handheld job where you have to hold it for an extended period of time, as it is 55% heavier than the 179. The Fluke 179 is the sweet spot for handheld in my book due to its smaller size and weight, with the 756 being a close second if you need more features.
I don't know why anyone would use an 87V or 869 handheld or in the field, they are basically high feature high precision bench meters.
My choice for handheld field use would be the likes of the BM235 or Fluke 117.
Although I can appreciate the likes of the ruggedised Fluke 27-II for extreme field use.
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I'd rather have the Brymen then the Fluke, as I regard it as overpriced and I dislike the idea of rewarding companies for such a policy.
Well, it seems you never had a fluke for a long time to work with.
At home I got a BM869s, at work we have tons of fluke meters, mostly 87V, some 187/189 and two 289, 15 or more 117 and 179 models.
We still have a 87 from 1990, it was calibrated over 30yrs every year without any issues.
I let my brymen calibrate in the year I bought it (2020) and it must be re-adjusted to reach it´s own specs...
Are you saying that from your professional experience Brymens don't maintain calibration for long(er) periods of time? Where did you send it to be calibrated (if not in-house?). Thanks :)
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Some users, myself included, have reported a bit of drift with the BM869 that may be an issue depending on your requirements: https://www.eevblog.com/forum/testgear/bymen-bm869-measurement-of-dcv-linearity/ (https://www.eevblog.com/forum/testgear/bymen-bm869-measurement-of-dcv-linearity/)
Fortunately the calibration/adjustment procedure for the BM869 is well known and easy to perform: https://www.jackenhack.com/calibrating-brymen-bm-series-multimeter/ (https://www.jackenhack.com/calibrating-brymen-bm-series-multimeter/)
If you calibrate/adjust the 500,000 count modes, you won't be disappointed.
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I don't know why anyone would use an 87V or 869 handheld or in the field, they are basically high feature high precision bench meters.
My choice for handheld field use would be the likes of the BM235 or Fluke 117.
Although I can appreciate the likes of the ruggedised Fluke 27-II for extreme field use.
Because I might be doing anything from poking around in a 3ph panel board to measuring charge current in a small fire alarm system.
I'd be happy to use the 869S but for its size.
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Because I might be doing anything from poking around in a 3ph panel board to measuring charge current in a small fire alarm system.
I'd be happy to use the 869S but for its size.
There is the Kane 555:
http://cn.kanetest.co.kr/shop.php?goPage=GoodDetail&g_code=20220330171318692&cat_no=2 (http://cn.kanetest.co.kr/shop.php?goPage=GoodDetail&g_code=20220330171318692&cat_no=2)
Basically a 121GW platform but with triple display, true energy measurement and motor stuff. But they dropped the 15V zener mode.
Or maybe:
https://catalog.chauvin-arnoux.com/fr_en/mtx-3291.html (https://catalog.chauvin-arnoux.com/fr_en/mtx-3291.html)
Smaller in all dimentions, weighs less at 570g
Or one of the Gossens maybe, but IIRC they won't be any smaller.
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There is the Kane 555:
... But they dropped the 15V zener mode.
From what I remember, the zener mode made it difficult to protect the meter from transients. Maybe the 555 is more robust.
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Some users, myself included, have reported a bit of drift with the BM869 that may be an issue depending on your requirements: https://www.eevblog.com/forum/testgear/bymen-bm869-measurement-of-dcv-linearity/ (https://www.eevblog.com/forum/testgear/bymen-bm869-measurement-of-dcv-linearity/)
Fortunately the calibration/adjustment procedure for the BM869 is well known and easy to perform: https://www.jackenhack.com/calibrating-brymen-bm-series-multimeter/ (https://www.jackenhack.com/calibrating-brymen-bm-series-multimeter/)
If you calibrate/adjust the 500,000 count modes, you won't be disappointed.
I bought my first BM869s seven years ago. Keeping in mind, I damaged the meter during my testing and then personally repaired it. It has never been aligned and spends most of the time on my bench. I do not have any way to check the meter for calibration but just ran a quick spot check at 10V, 1V, 1mV, 40 ohms and 1.9M. The 40 ohm is an S102K 0.005% +/-1PPM. The 1.9M is a Caddock TK, which measured 1.900005 last time I checked it. For voltage, I am using my vintage Fluke 731B standard.
I have the second one if you would like me to check it. Brymen had provided that meter to run my 50,000 life cycle test on. I also dropped it. Damaged the front end during transient testing. During repairs, I used some different parts to allow it to survive to even higher levels (so modified). It also has never been aligned.
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My choice for handheld field use would be the likes of the BM235 or Fluke 117.
Although I can appreciate the likes of the ruggedised Fluke 27-II for extreme field use.
I don't know the 87V is the meter I use in the field. It's good but I don't feel it's a high precision meter.
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I don't know the 87V is the meter I use in the field. It's good but I don't feel it's a high precision meter.
Well, it was when it was first introduced 35 years ago :o
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I don't know the 87V is the meter I use in the field. It's good but I don't feel it's a high precision meter.
Well, it was when it was first introduced 35 years ago :o
Although it's capable of 20,000 count meter it's basically a 6,000 meter.
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I still use my cheapo Mastech meter for working on the bikes. It's stored in a trailer outside where it freezes in the winter and cooks in the summer. The only features I use are resistance, DCV and temperature. +/-5% would be fine.
I have had a need for a scope from time to time. Once I had a wheel speed sensor problem. I had a power inverter in the car running my analog scope in the seat with a cable running out the back window. :-DD A few years back I bought a couple of Fluke 89 scope meters which fill any of my portable scope needs. If they were not so long in the tooth, I would just use these for all of my garage work as their DMM functions cover the basics.
Normally I am not trying to hold the meter while I work. I normally need my hands for other things (hold probes, making mechanical adjustments...). The larger screens work out well. The Mastech's LCD will wash out (turn black) in the sun so it has that going for it. Cheap meter.
Before getting the BM869s, I used my bench meters for everything in the lab. Now I use the handheld the majority of the time. The closest handheld I have seen to my bench meter was that Gossen Ultra. Still, at $900 , it's no match for my vintage HP and would need work before it could be used (lack of shielding is a ball buster, good job germany).
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Because I might be doing anything from poking around in a 3ph panel board to measuring charge current in a small fire alarm system.
I'd be happy to use the 869S but for its size.
There is the Kane 555:
http://cn.kanetest.co.kr/shop.php?goPage=GoodDetail&g_code=20220330171318692&cat_no=2 (http://cn.kanetest.co.kr/shop.php?goPage=GoodDetail&g_code=20220330171318692&cat_no=2)
Basically a 121GW platform but with triple display, true energy measurement and motor stuff. But they dropped the 15V zener mode.
Or maybe:
https://catalog.chauvin-arnoux.com/fr_en/mtx-3291.html (https://catalog.chauvin-arnoux.com/fr_en/mtx-3291.html)
Smaller in all dimentions, weighs less at 570g
Or one of the Gossens maybe, but IIRC they won't be any smaller.
I just remembered the lack of a useful touch-hold on the 869S. This is quite important when you need to see where you're putting your hands inside a live cabinet, and can't spare the attention for the meter screen. The 78x meters have it I understand, but until my 87V, 27A/N, Metrix MX 57Ex, and Tek 912 are all dead, I'm not really in the market for a new work meter...
:-DD
I note you haven't quibbled about the chemical resistance, and missed off your list of PE uses "bottles for hydrofluoric acid", which I'll grant is a fringe case, so perhaps "fuel can" is more mainstream.
Take a Fluke 87 V and Brymen 869S, chill them down to oh, -10 Celcius or so, then drop them onto concrete from 3m.
Lots of fringe cases here, but while gasoline might give PC a slightly hard time, it's really not where a typical Brymen get's used. As for -10C, well they make snowmobile helmets, goggles and face shields from PC too.
HDPE is a good material for sure. I'm just not convinced it's as tough as or any better than PC. HDPE is less expensive than PC though so I guess that's why Fluke can make meters that are so budget friendly. :-//
I'd disagree about solvents in particular being a fringe case; acids yes.
It would be interesting to do some properly calibrated drop tests. My guess is that PE gives a better damped impact than PC, so would be friendlier to the internals... Time for Dave to bring his occasionally mooted physical torture test chamber into reality?
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
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Hi,
Are you saying that from your professional experience Brymens don't maintain calibration for long(er) periods of time?
Maybe my Brymen was a one-off, I was just surprised that a brand new factory calibrated multimeter had to be readjusted in a few areas during external calibration to get within its own specifications.
I don't know that at all from the Fluke models at work.
I've been employed there in the testfield since 2003 and am now the manager and jointly responsible for the measuring equipment used.
We have a database for this measuring equipment, where all calibrations since procurement are stored and of course also failures.
No Fluke has ever failed in these years.
Even an ancient Fluke 8060A (100khz TRMS !!!) has survived every calibration until its "natural" retirement.
This is a quality that Brymen must first prove over the decades.
That is why I personally do not let anything come on Fluke meters, it is simply professional quality that has its price and they are simply the industry standard.
Still, I like my BM869s, it has many good approaches and is hard to beat for the money.
And you can buy almost 3 BM869s for the nominal price of an 87V, so it wasn't hard for me to decide for personal use.
Where did you send it to be calibrated (if not in-house?). Thanks :)
Welectron offers a calibration service, not only for multimeters (you can choose) and either according to ISO or even DakkS.
They don't do it themselves, they then send it on to the lab.
https://www.welectron.com/Brymen-Multimeter-BM780-BM850s-BM860s-ISO-Calibration (https://www.welectron.com/Brymen-Multimeter-BM780-BM850s-BM860s-ISO-Calibration)
I think this service is good, as a private person you usually can't get it so easily.
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
Again, I want to be clear, "I do not have any way to check the meter for calibration .." The standard I have is not in cal, nor are any of my resistors. That Fluke standard does not provide a 5V level, so you get what you get. If I need to know what the meter is doing beyond this, I would have it calibrated and request a report. Sure it would cost me about as much as the meter but I fully understand the cost of maintaining a calibration lab. I have done this for some equipment I own. In the case of the 869s 500k count mode, any time I have used it, it was for a relative measurement. I typically do not need the absolute accuracy.
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
Again, I want to be clear, "I do not have any way to check the meter for calibration .." The standard I have is not in cal, nor are any of my resistors. That Fluke standard does not provide a 5V level, so you get what you get. If I need to know what the meter is doing beyond this, I would have it calibrated and request a report. Sure it would cost me about as much as the meter but I fully understand the cost of maintaining a calibration lab. I have done this for some equipment I own. In the case of the 869s 500k count mode, any time I have used it, it was for a relative measurement. I typically do not need the absolute accuracy.
Fair enough if you don't have a calibrated 5V reference, but what about a 6.5 digit DMM? DCV Calibration points for the BM869 would be short, 5V, 50V, etc.
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
fwiw (not much) my 869S, which has had a hard life, agrees with my (relatively recently) calibrated Fluke 8840A to within around a millivolt or so, with a 5 volt source applied.
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How much is the Brymen 869 or 789 if I were to buy one in the USA? I don't even know where to buy it but I guess it can be done. I haven't seen a Brymen any model in real life and I am curious an want to try them out.
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Maybe my Brymen was a one-off, I was just surprised that a brand new factory calibrated multimeter had to be readjusted in a few areas during external calibration to get within its own specifications.
Seems that way.
Mine is about 5 years old now and either hasn't drifted at all or has drifted at exactly the same rate as my other meters and voltage reverences (which would be too big a coincidence to believe...)
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Of course accuracy is going to be a balance between fringe use cases and cost. The designer of the Fluke 8060A admitted they went the extra mile on it:
https://theamphour.com/180-an-interview-with-dave-taylor-multi-talented-meter-maker/
In my experience my 87V and 287 (both with calibration data) seem to have still gotten some premium treatment since they far exceed their specs. But I've only had them for about 4 years at this point.
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
fwiw (not much) my 869S, which has had a hard life, agrees with my (relatively recently) calibrated Fluke 8840A to within around a millivolt or so, with a 5 volt source applied.
That could be about 100 counts out or more in 500,000 count mode, which is similar to what I and some others have experienced. After an adjustment some year or so ago, my BM869s is still within about 15 counts worse case, which was about 10c from the calibration temperature and at first power on. At the same temperature as the calibration and a few minutes after power on, it's within about 1-2 counts.
So this just points out the odd situation of why some of us received units that were so far out, and also points out that it is VERY capable in 500,000 count mode assuming you adjust it if it needs it.
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
Again, I want to be clear, "I do not have any way to check the meter for calibration .." The standard I have is not in cal, nor are any of my resistors. That Fluke standard does not provide a 5V level, so you get what you get. If I need to know what the meter is doing beyond this, I would have it calibrated and request a report. Sure it would cost me about as much as the meter but I fully understand the cost of maintaining a calibration lab. I have done this for some equipment I own. In the case of the 869s 500k count mode, any time I have used it, it was for a relative measurement. I typically do not need the absolute accuracy.
Fair enough if you don't have a calibrated 5V reference, but what about a 6.5 digit DMM? DCV Calibration points for the BM869 would be short, 5V, 50V, etc.
I had it calibrated last maybe 10-15 years ago. Thought about having it done after the lighting storm took it out but after seeing it only damaged the GPIB interface, decided to leave it.
Nothing in my home lab is currently calibrated. I would only be chasing my tail and adding more error.
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How much is the Brymen 869 or 789 if I were to buy one in the USA? I don't even know where to buy it but I guess it can be done. I haven't seen a Brymen any model in real life and I am curious an want to try them out.
Other than Dave's BM235 and BM786 available on Amazon, Brymen-branded meters aren't directly marketed in the US. You can find re-brands like Greenlee and FLIR, but they typically charge a high premium for essentially the same meter (of course you then get a US warranty and support/repair options).
To get a Brymen-branded meter you'll need to import one from a European dealer like TME or Welectron. I've ordered from both, and prefer the latter. Welectron has the best prices even after currency conversion plus have a flat $10 shipping rate for most things that gets it here in about a week.
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How much is the Brymen 869 or 789 if I were to buy one in the USA? I don't even know where to buy it but I guess it can be done. I haven't seen a Brymen any model in real life and I am curious an want to try them out.
Other than Dave's BM235 and BM786 available on Amazon, Brymen-branded meters aren't directly marketed in the US. You can find re-brands like Greenlee and FLIR, but they typically charge a high premium for essentially the same meter (of course you then get a US warranty and support/repair options).
To get a Brymen-branded meter you'll need to import one from a European dealer like TME or Welectron. I've ordered from both, and prefer the latter. Welectron has the best prices even after currency conversion plus have a flat $10 shipping rate for most things that gets it here in about a week.
+1 on 789 from Europe
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To get a Brymen-branded meter you'll need to import one from a European dealer like TME or Welectron. I've ordered from both, and prefer the latter. Welectron has the best prices even after currency conversion plus have a flat $10 shipping rate for most things that gets it here in about a week.
When ordering from welectron to the USA you also don't pay sales tax, which for me is nearly a 10% discount. And you don't pay VAT, so what you're charged might be less than the prices you're quoted at first (depends on if they know where you are when putting things into the cart). Tax dodges that work for the little guy!
Email them for an eevblog discount code (5% I think).
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Try "marcoreps5" for the coupon code (5%).
Edit: Pic.
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Benning sells a modified version of BM789. LCD was a bit changed and there is only one channel temperature measurement. I do not see an improvement here. Buttons were renamed and moved.
https://www.benning.de/products-en/testing-measuring-and-safety-equipment/digital-multimeter/high-end-multimeter-mm-7-2.html (https://www.benning.de/products-en/testing-measuring-and-safety-equipment/digital-multimeter/high-end-multimeter-mm-7-2.html)
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For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.
Again, I want to be clear, "I do not have any way to check the meter for calibration .." The standard I have is not in cal, nor are any of my resistors. That Fluke standard does not provide a 5V level, so you get what you get. If I need to know what the meter is doing beyond this, I would have it calibrated and request a report. Sure it would cost me about as much as the meter but I fully understand the cost of maintaining a calibration lab. I have done this for some equipment I own. In the case of the 869s 500k count mode, any time I have used it, it was for a relative measurement. I typically do not need the absolute accuracy.
Fair enough if you don't have a calibrated 5V reference, but what about a 6.5 digit DMM? DCV Calibration points for the BM869 would be short, 5V, 50V, etc.
I had it calibrated last maybe 10-15 years ago. Thought about having it done after the lighting storm took it out but after seeing it only damaged the GPIB interface, decided to leave it.
Nothing in my home lab is currently calibrated. I would only be chasing my tail and adding more error.
But if you like to chasing your tail, showing the Fluke 731B standard set to 10V with a follower/divider. My HP34401A (not calibrated) used as a reference and trimmed to 5V. Seems like this is what you are asking for. BM869s was is the one supplied by Brymen for my testing. This meter was subjected to my 50,000 cycle test of the switch. I also repeated my transient tests on it and damaged it. I then selected different transistors for the clamp and re-transient tested the meter to 14kV. So, it doesn't have the original parts installed. I have never made any attempt to align the meter. This meter is about 5 years old now but after my abuse, maybe closer to 30 years. :-DD
Still my favorite meter.
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Benning sells a modified version of BM789. LCD was a bit changed and there is only one channel temperature measurement. I do not see an improvement here.
One temperature measurement sounds like the EEVblog BM786. I didn't look close enough to see if they are otherwise functionally the same. However, I did track down a clue to the cost in a press release (I didn't find any mention of the price on the linked page):
the current selling price of less than 300 euros is extremely reasonable
Instead get the BM786 or BM789 for under 200 EUR (often far less). Great meters - especially for the price.
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- Welectron has various 5% discount codes, I typically use the EEVblog one. You can just e-mail them to request a code if needed or if they read this thread and discontinue them. Also, these codes don't apply to all products.
- From photos of the BM78x PCBs, there are other possible model numbers that Brymen has ready to offer, such as 783 up through 789 (of course) and also a Bluetooth option. The Benning 7-2 is not the same as the BM786 as it is missing some things such as nS. It seems Benning and/or Brymen are planning for other possible models with more features, as the LCD photo shows. I also find it interesting that the Bluetooth connection icon is present, as also seen on the BM78x series (D icon). If the Benning came out later, is Brymen still planning to add Bluetooth at some point? Since they already used up the BM789 model number, perhaps they will move to BM790 or BM789+?
- Making some assumptions about the 731B and 34401A, 27 counts high on the BM869s is not a problem, but if it were mine I would lock in the 5V calibration point just because it's so easy to obtain a calibrated 5V reference and the extra digits are welcome.
- I did discover a situation where the A range (5A/10A) on my BM869s has an accuracy issue vs. my BM789. Test conditions: briefly verify that a measurement at 0.5A is correct (use auto-range), then push 9A through for 60 seconds. Notice that the 9A reading should have minimal drift during this time, maybe 5 counts.
Now drop back down to 0.5A and at least with my BM869s the accuracy has suffered significantly and is out of spec. For example, I got 0.4841A, while spec says no more than 0.0045A off. The cause appears to be primarily an issue with the zero reference point which you can see if you remove the common input completely (leave A input jack inserted). There is a large negative offset.
Over time, the BM869s returns to full accuracy.
The BM789 does not drift nearly as much in the same situation (~15 counts off, worse case).
I tested a few other handheld DMMs and some drift was common, but couldn't find any that were anywhere nearly as bad the BM869s.
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... but if it were mine I would lock in the 5V calibration point just because it's so easy to obtain a calibrated 5V reference and the extra digits are welcome.
The only time I have used the higher resolution on the BM869s was for relative measurements. If I need better absolute accuracy, it would be going in for alignment and calibration with a report. Outside of that, I would just be kidding myself. I have no reference good enough to give me any level of confidence that any improvements were made.
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... I would lock in the 5V calibration point just because it's so easy to obtain a calibrated 5V reference and the extra digits are welcome.
I looked to see what it would cost to rent a Fluke calibrator but would have to create an account just to get a quote. I'm sure sending the meter out would be less costly but I would need to talk with the cal house to get a quote on alignment. Guessing they would need to manually align the BM869s.
I'm interested in hearing about the easy to obtain reference you mention. I'm not thinking I could find anything NIST traceable easily.
There are those cheap references on ebay but I'm sure you're not suggesting using one of them as your standard to align your meters with. I could have the HP sent off and get a report, then transfer from that. A pain but may be the easiest way to go.
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https://voltagestandard.com/01%25-voltage-references
The VREF5-01 features a 5V output, accurate within 0.01% (output guaranteed to be between 4.9995 and 5.0005 Volts) for a minimum of 8 months.
My BM869s was 0.00027 from my HP.
There's this one:
https://dmmcheckplus.com/
According to their website, their cal standards are out of date. So would I trust to use it to align a meter, nope.
https://img1.wsimg.com/blobby/go/c544540f-524c-4b38-8d0c-cbfda88bf37a/downloads/2022%203458A%20Calibration.pdf?ver=1691065892806
Just chasing your tail with this stuff. Maybe good for a sanity check like my white box but if I need accuracy, the meters would be properly aligned or just calibrated with a report so I can calculate the error.
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Benning sells a modified version of BM789. LCD was a bit changed and there is only one channel temperature measurement. I do not see an improvement here.
One temperature measurement sounds like the EEVblog BM786.
The BM786 is exclusive to me.
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Yes, I was thinking of Doug's VREF-01 product. I've had two of them for over 4 years and have the calibration data for each yearly calibration. For the 5V reference, 1 year drift was:
5.00009V
5.00012V
5.00013V
(Each year it is set to exactly 5.00000V)
HOWEVER, the best course of action is to use the reference as soon as you receive it, since the drift will be negligible. Doug also provides the calibration temperature so you can match it to your environment. I always check mine right after receiving them and they are spot on.
I have not found the DMMCheckPlus to be QUITE as awesome, as the calibration printout only reports 5.0000V while Doug adds an extra digit to the as-received and post-calibration measurements.
Russ @ DMMCheckPlus has just not updated the website with the current equipment calibration dates. I received my unit back a couple months ago and it shows the 3458A with a calibration due date of 5/01/2024.
For hobby use, having at least some basic references that have been mailed out for verification is plenty good to take things up a notch. I agree the BM869s at face value doesn't appear too far off, but without at least something to use as a reference we are mostly guessing, although the 34401A is pretty trustworthy in general.
So with that said, I would totally vote for shipping that 34401A out for calibration. It's nice to have something that can be expected to be very stable due to age and the money is far better spent there than with the BM869s.
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Yes, I was thinking of Doug's VREF-01 product. I've had two of them for over 4 years and have the calibration data for each yearly calibration.
....
(Each year it is set to exactly 5.00000V)
It sounds like you are having them align your VREF-01 every year to some (???) reference they have. We assume that their reference is in cal and they provide you with that error report. Otherwise, the exactly 5.000000V is meaningless. There is a reason I want that standard tied to NIST under current cal.
For hobby use, having at least some basic references that have been mailed out for verification is plenty good to take things up a notch.
Hard to say really. You may be doing more harm that good aligning your meters to these cheap references. Personally, I cross check my Fluke standard with the old HP and then against the BM869s, good enough. Getting anything better, I am going with a calibration lab that has the proper equipment to calibrate them (not align). Sure, it's going to cost me some cash and down time but beats chasing your tail if you really need that level of absolute accuracy.
I've taken my white box into work and checked it against equipment that is in current calibration. It's good enough to tell me if the meters I test have started to fail. Really though, that's all I use it for.
I saved an old Fluke thermal RMS bench meter from the recycle that needed a lot of work. Once repaired, I did go through the alignment using my old HP34401A as a reference. I left the AC section alone as the Fluke would require something much better than the HP to align it. That's about as close as I have come to trying to align a meter. I would never suggest ether meter is in cal.
I am running a long term poor man's drift study on a cheap handheld meter that I hacked up. Looks like it's due to me checked again. Keep in mind that non of the standards used are calibrated. What we can see if that at least this particular meter doesn't live up to all they hype about drift on cheap meters.
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The voltage references from VoltageStandard.com and DMMCheckplus.com are adjusted to their stated value at each calibration. This is how they are designed/marketed. I'm sure you could decline the adjustment, but there are advantages to having them set to a specific value.
Of course Doug @ Voltage Standard also uses a calibrated 3458A, currently due for calibration on 3/22/2024: https://voltagestandard.com/001%25-10v-reference
Actually it's easy to say: I have four calibrated DMMs with data and five calibrated references with data so I wouldn't have suggested using the VREF-01 to set the BM869s 5V calibration point if I thought it would do more harm than good. It's been well documented in other threads that the BM869s can be off by quite a bit and yearly calibrations/adjustments can tighten it up to make it significantly better. I've also documented that the VREF-01 is excellent and best right after calibration/adjustment.
But as I said that is really just a small step above having no calibrated equipment. So why not ship the 34401A and 731B off once for calibration? Age is great for stability. Then snag the VREF10 to use for yearly verifications.
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So why not ship the 34401A and 731B off once for calibration? Age is great for stability. Then snag the VREF10 to use for yearly verifications.
As I have stated, I did have the HP in for cal 10-15 years ago. I had bought the meter brand new from HP when it was first released and was curious how it had changed so I had a full report created. Having my equipment calibrated to NIST standards wouldn't enhance my hobby. Using a cheap standards to try and align things, even less so.
Of course, shipping out the equipment poses a risk. Then there is the question of if the company doing the work is actually capable.
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Hi Joe,
I understand your concern with shipping equipments. Depending on where your lab is, it may worth checking around. Both Keysight and a local cal lab came to my lab to pick up my DMMs when calibrations are due. The local cal lab hand deliver the DMMs back when it is done, Keysight ship it directly from their cal lab (which is not local) in their own packaging, which was very carefully packaged.
Good luck, in my 34401As, 34461A, and 34465A, they are extremely stable, annual drift are minimal, usually they only have to adjust 1-2 alignments in different ranges. But if you have not had yours done in 10-15 years, it may worth the effort if absolute accuracy is important to you, or if your DMMs are required to have current cal due to the type of work you do.
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Hi Joe,
...
Depending on where your lab is, it may worth checking around.
...
In my house, in a spare room. It's not a business.
But if you have not had yours done in 10-15 years, it may worth the effort if absolute accuracy is important to you, or if your DMMs are required to have current cal due to the type of work you do.
My hobby doesn't require any of my equipment to be in cal. When I had it calibrated, it was more out of curiosity of how much it drifted. No alignment was performed. So it's never been aligned since shipped from the factory. That's true for my other HP bench meter as well.
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We're definitely off topic at this stage, but another reason the references being discussed are popular is because calibration is easy and inexpensive. Maybe $5 each way for shipping plus the calibration fee which is only charged after the 2nd year. So you don't need to ship out your precious.
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We're definitely off topic at this stage, but another reason the references being discussed are popular is because calibration is easy and inexpensive. Maybe $5 each way for shipping plus the calibration fee which is only charged after the 2nd year. So you don't need to ship out your precious.
:-DD :-DD :-DD
It would be very naive to think one data point even if it was NIST traceable is considered calibration. When I had my HP meters calibrated, the reports are lengthy. They have to check every mode, every range, several points per range, in controlled environment, after it has warmed up. For the HP meters, its all automatic using their software but for the BM869s, I suspect it would all be manually performed. When I had the HP's cal'ed I think it was around $150/ea. That was with the report. I assume the costs have gone up over the last 10 years. The next problem is your cheap standards are not going to be near good enough, even for that one data point. Part of what I am paying for is the lab's equipment. The calibrator required for a free harbor freight meter is not the same that is required for the HP34401A.
Again, if I need the accuracy, I'm have them done by an accredited lab. I'm not going to waste any time fooling myself.
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When I had the HP's cal'ed I think it was around $150/ea. That was with the report. I assume the costs have gone up over the last 10 years.
When I last checked with a local calibration facility a couple of years ago to have my newly acquired Agilent 34401A calibrated, I was quoted $492 for an A2LA Certification. That was local drop-off & pickup, no shipping included.
I'm a hobbyist and couldn't care less about A2LA or NIST traceability, I just wanted to know for sure that the almost 20 year old meter I'd bought was as accurate as it was capable of, but that price was double what I paid for the meter. So I satisfied myself with my little cheap Chinese references (more than one though, to at least give me a better sample size).
I received my new SDM3065X yesterday and compared it to my warmed-up 34401A, and for DCV and resistance they were identical to the last digit in most cases, in the other cases they were off by 1 count. I was really surprised as I have no clue when the 34401A was last aligned/calibrated, but they are legendary for their stability. The BM869s was used for capacitance comparison since the 34401A doesn't have it, and while it didn't have as many digits it also matched exactly.
I'll take that as plenty good enough for my purposes, and save the calibration money for another piece of test gear.
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I can believe five bills on the 34401A today.
I picked up a used Agilent PNA and looked into having it checked at Keysight for much the same reason you looked at having your meter calibrated. In my case, I didn't get to a quote as it was so old they no longer offered any service for it. :-DD
The white box I use makes for a decent quick sanity check. It has a fair number of low temp co decent tolerance resistors, decent APEX voltage reference and a few other bits. Guessing I have about $500 in that. The reference IC alone would be over $100. Not good enough for calibration but that was never the intent. As you say, plenty good enough for my purposes.
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I note you haven't quibbled about the chemical resistance, and missed off your list of PE uses "bottles for hydrofluoric acid", which I'll grant is a fringe case, so perhaps "fuel can" is more mainstream.
You think the display glass on the fluke meter is made from PE?
I'm pretty sure it isn't. And I think that is also the part of the meter which will be the part most likely damaged and the part where damage is most visible.
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Hi,
Are you saying that from your professional experience Brymens don't maintain calibration for long(er) periods of time?
Maybe my Brymen was a one-off, I was just surprised that a brand new factory calibrated multimeter had to be readjusted in a few areas during external calibration to get within its own specifications.
I don't know that at all from the Fluke models at work.
I've been employed there in the testfield since 2003 and am now the manager and jointly responsible for the measuring equipment used.
We have a database for this measuring equipment, where all calibrations since procurement are stored and of course also failures.
No Fluke has ever failed in these years.
Even an ancient Fluke 8060A (100khz TRMS !!!) has survived every calibration until its "natural" retirement.
This is a quality that Brymen must first prove over the decades.
That is why I personally do not let anything come on Fluke meters, it is simply professional quality that has its price and they are simply the industry standard.
Still, I like my BM869s, it has many good approaches and is hard to beat for the money.
And you can buy almost 3 BM869s for the nominal price of an 87V, so it wasn't hard for me to decide for personal use.
Where did you send it to be calibrated (if not in-house?). Thanks :)
Welectron offers a calibration service, not only for multimeters (you can choose) and either according to ISO or even DakkS.
They don't do it themselves, they then send it on to the lab.
https://www.welectron.com/Brymen-Multimeter-BM780-BM850s-BM860s-ISO-Calibration (https://www.welectron.com/Brymen-Multimeter-BM780-BM850s-BM860s-ISO-Calibration)
I think this service is good, as a private person you usually can't get it so easily.
I have my Brymen BM869s ISO 17025 calibrated every year, for about 5 years now, and it always passes.
And in those years I've used different labs, including the one that welectron uses.
Also DakkS is an ISO calibration (ISO 17025) so it is a bit confusing that you use ISO without a number (you're probably refering to ISO 9001 if I were to guess).
BTW, the lab that Welectron uses (Esenwein) can't calibrate all functions of the BM869S according to ISO17025. I don't know if Welectron communicates that, but if you seek direct contact with Esenwein they'll tell you that in advance. I think it was capacitance and temperature, but don't hold me to that. For those parameters you get an ISO9001 calibration (so non traceable to national standards).
For me, that wasn't important, I need the calibration purely for DCV and DCmV. For the rest, their service is fine and their price is good.
I don't know why your meter failed calibration, but I'd say based on my own yearly experience that it's not normal.
For me, the BM869S is a very stable multimeter based on 5 years of annual calibrations. You can also see that in one of Dave's recent video's where he pointed out that the specs on DC current on his 786 were better than on the BM869S. However while he was saying this, in his test setup his 786 measured exactly the same value as his 10+ years old BM869, to the last digit. I call that a win for the BM869 no matter what the manual says!
So to me, the BM869S is a very accurate and stable multimeter. Is it more stable than a Fluke? Fluke also makes very good and stable multimeters. However, Fluke doesn't offer a multimeter that is that accurate or has that high of a resolution on the electrical parameters that I use (DC mV and the lower DC V ranges). So hard to say if Fluke would offer such a handheld meter, that it then would be that stable and accurate ;)
All I can say is that for my use, so the BM869s with interface cable of which I log with 200ms interval (I'm basically measuring electric charge, coulomb), is a setup that costs basically about €270, with the leads, pouch, usb interface etc (that's including VAT). If I were to go to fluke, only the 289 FVF package (basically the same content as the €270 brymen package) could do the same. That package costs about €1120 (incl vat). That's over 4 times as expensive. For that I get a multimeter with lesser factory accuarcy specs, lesser resolution and I think a slower logging interval (I think the 289 can only log every second, so 5 times as slow as the BM869s can).
That is a very easy choice to make for me.
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especially when you consider the 869 is more designed as a precision high count lab meter than a field test meter.
The BM869S has rubber seals on each seam, including the input jacks. I don't call that particularly a designfeature for a lab meter.
For me, that's something useful for in the field.
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.. I need the calibration purely for DCV and DCmV.
Good suggestion so here is another data point.
It appears I purchased the my first BM869s in October 2016 from TME. So its almost seven years old now. Again, this meter was damaged during my transient tests. I performed the repairs using OEM parts (unlike the other meter). Outside of that, this meter hasn't seen a lot of abuse. It is however the most used meter I have. Like the other BM869s, it has never been aligned.
Brymen specs 0.02% +2d, so 500mV +120uV
Again, using the Fluke 731B reference with a divider trimmed to 0.5V with my HP34401A, the Brymen is 30uV offset. Again, nothing is in cal and I make no claim about the absolute accuracy. Still, it's hard not to draw the conclusion that both of these meters would most likely pass calibration if I sent them in.
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For a sanity check of the setup, let's look at one other meter. This is my Gossen Metrawatt M248B Ultra which is six years old. While I never damaged the meter, I did have to make several modifications to the German design to get it to perform to American standards. :box: Really a shame as this meter has the potential. This meter has never been aligned but it was put though my battery of tests.
I was going to show the last 121GW meter I purchased that was never modified or abused in any way. That meter just bounces all over the place.
Anyway, maybe this provides a bit more confidence in the setup.
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I note you haven't quibbled about the chemical resistance, and missed off your list of PE uses "bottles for hydrofluoric acid", which I'll grant is a fringe case, so perhaps "fuel can" is more mainstream.
You think the display glass on the fluke meter is made from PE?
I'm pretty sure it isn't. And I think that is also the part of the meter which will be the part most likely damaged and the part where damage is most visible.
If you take but a moment to actually think about it, the most likely parts of the meter to come into contact with such substances in a lab or workshop are the holster/back, range switch, and buttons.
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If you take but a moment to actually think about it, the most likely parts of the meter to come into contact with such substances in a lab or workshop are the holster/back, range switch, and buttons.
How so?
If your meter gets splashed with acid, it always miraculously misses the display?
Anyway, for PC to get affected by hydrochloric acid and PE not, that's usually a matter of days if not weeks. You'll have time enough to clean the housing of your meter.
Where the real danger lies is ingress. Both the Fluke 87V as the Brymen BM869s have some ingress protection by having internal seals around the jacks etc.
But by then the acid probably also already got into the jacks, eating away at the metal.
If getting splashed by acid is a real scenario for your DMM use, you should pick your meter based on whether or not it's IP67 rated with sealing plugs on the open jacks, not based on if the housing is made from PE or PC imho.
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If you take but a moment to actually think about it, the most likely parts of the meter to come into contact with such substances in a lab or workshop are the holster/back, range switch, and buttons.
How so?
If your meter gets splashed with acid, it always miraculously misses the display?
Anyway, for PC to get affected by hydrochloric acid and PE not, that's usually a matter of days if not weeks. You'll have time enough to clean the housing of your meter.
Where the real danger lies is ingress. Both the Fluke 87V as the Brymen BM869s have some ingress protection by having internal seals around the jacks etc.
But by then the acid probably also already got into the jacks, eating away at the metal.
If getting splashed by acid is a real scenario for your DMM use, you should pick your meter based on whether or not it's IP67 rated with sealing plugs on the open jacks, not based on if the housing is made from PE or PC imho.
That's not a good example imo. Splashing is unlikely unless you're pretty clumsy, and if you are I don't want to work in the same lab or workshop as you.
A far more likely scenario is contact via contaminated gloves, which is going to be common in any busy workshop.
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Well than it's only very minor quantities and you'll have plenty time to clean the meter before the acid actually starts eating away at the plastic.
Maybe it would be more useful to test the ink from the lettering to test it's resistance to acids. I can't imagine that the ink will be more resistant to acid than the plastic, being either PC or PE, let alone eating away that the meter becomes unuseable but with the lettering still on it.
So if that's the only thing you worry about in choosing a meter and want a definitive answer, you'd have to wait until Joe Smith adapts his destructive tests to include various acids in various strength to the lettering, display, plastic and rubber boot.
Or do the testing yourself, as I doubt Fluke or Brymen do these tests with various acids in various strengths.
I works with acids and other corrosive anorganic chemicals all the time (I work in galvanics so highly concentrated acids (in very very large quantities) are no stranger to me), and generally plastics getting attacked by corrosive anorganic chemicals isn't a real problem. Not during the timespan we're talking about. If you're constructing a tank were acids sit in for years, sure, you'd want a tested HDPE or HDPP, but that's a completely different situation.
Besides, if you're handling acids in the concentrations and quantities we're talking about, that could actually start eating away at PC if left over time, you're not working with your standard nitrile doctors gloves anymore.
You'll be wearing really thick synthetic gloves that go up sleeves, and those are usually not the kind of gloves that make operating a multimeter very easy. Certainly not that easy that only the knob is touched and never the display. At least that's my experience when I work with electronic equipment and galvanic chemicals at the same time (and yes, that happens. Not the use of a dmm, but the use of specialized rectifiers and other specialized tools)
So I just don't really see the real world scenario that you have in your head.
The chance that the meter falls of a desk or cabinet is much more likely, so impact resistance of the plastic the housing is made of is way more important. So I guess that is why manufacturers test that and give a spec on that, and not it's chemical compatibility to acids.
Besides if these situations occur in a lab, anorganic chemicals that are that potent that they affect plastics, will only be used under a fume hood. If some worker walks away from that still with his gloves on drenched in the stuff to a bench where a dmm is set up, he'll be denying a lot of H&S regulations, risking his co workers way more than a potential DMM. And if the DMM is set up in the fume hood, it becomes a specialized piece of equipment that probably will be tested in advance if it is suitable for that space and there'd be a protocol how to use it.
The most likely situation of a DMM being exposed to a fairly strong acid is I think in a garage, where some amateur is tinkering away with battery acid (37% sulfuric acid) and is getting it over his multimeter. Althoug I don't think it'll attack the PC plastic unless it's a fair amount and left to dry in for days. I imagine the lettering being gone long before that.
Can't fix stupid, can you?
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I bought a couple of used Fluke 97s from an garage. Both meters have damage from splash or over spray. When I work on the bikes, the worse chemicals are gasoline (some cocktail of ???) and methanol. I expose the meters I review to these and it's pretty amazing the difference I see between manufactures. The two problems areas seem to be the screen and lettering.
If you are interested in seeing how unstable my 121GW is compared with the other two, I made a short clip. Note, this is the 121GW that was never exposed to any of my testing. From what I remember, Dave was selling old stock which is what I received for the review so it is not the latest hardware. The firmware of the day was 2.02. They were playing a lot with the filters and maybe there is a version that is more stable but slower response??
https://www.youtube.com/watch?v=dnnPDajITqM (https://www.youtube.com/watch?v=dnnPDajITqM)
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If you are interested in seeing how unstable my 121GW is compared with the other two, I made a short clip. Note, this is the 121GW that was never exposed to any of my testing. From what I remember, Dave was selling old stock which is what I received for the review so it is not the latest hardware. The firmware of the day was 2.02. They were playing a lot with the filters and maybe there is a version that is more stable but slower response??
Wow thats just crazy. Thanks for that video.
If a meter keeps hunting around for a certain stable value, what's the point of having a high resolution meter?
Especially in my situation, where I want to log from the meter at a reasonable speed because the value I'm measuring is gradually creeping up or down. The faster the logging, the more accurate the calculated value that's using this input.
I can't imagine how that would look like with a meter that keeps wandering around in such a measuring session. Probably just a very hazy graph line :-DD
And it's quite a bit too, I see 499,78 and 500,19. So 0,41mV uncertainty. Over 0,08%
If you'd only see the one meter and not knowing its measured source, you'd say it's an unstabilized rectified ac transformer or something like that. Certainly not a DC reference standard!
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The second one was damaged beyond repair during my evaluation of it or I would repeat the stability test using it. I do have that prototype 121GW that Dave graciously provided but being a prototype and then my hacking the crap out of it, I don't think we would learn anything by looking at it. Someone else with a 121GW would need to look at theirs. Maybe the newer ones are more stable.
However, this thread was really about the BM789 and it only seems fitting that I show mine. Again, this meter (along with all of my BM78x meters) was provided by Brymen during the development of the meter. This particular one was after the final changes. I have never changed anything with the hardware or touched the alignment.
https://www.youtube.com/watch?v=_Irr6XNmgr0 (https://www.youtube.com/watch?v=_Irr6XNmgr0)
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Well than it's only very minor quantities and you'll have plenty time to clean the meter before the acid actually starts eating away at the plastic.
Maybe it would be more useful to test the ink from the lettering to test it's resistance to acids. I can't imagine that the ink will be more resistant to acid than the plastic, being either PC or PE, let alone eating away that the meter becomes unuseable but with the lettering still on it.
So if that's the only thing you worry about in choosing a meter and want a definitive answer, you'd have to wait until Joe Smith adapts his destructive tests to include various acids in various strength to the lettering, display, plastic and rubber boot.
Or do the testing yourself, as I doubt Fluke or Brymen do these tests with various acids in various strengths.
I works with acids and other corrosive anorganic chemicals all the time (I work in galvanics so highly concentrated acids (in very very large quantities) are no stranger to me), and generally plastics getting attacked by corrosive anorganic chemicals isn't a real problem. Not during the timespan we're talking about. If you're constructing a tank were acids sit in for years, sure, you'd want a tested HDPE or HDPP, but that's a completely different situation.
Besides, if you're handling acids in the concentrations and quantities we're talking about, that could actually start eating away at PC if left over time, you're not working with your standard nitrile doctors gloves anymore.
You'll be wearing really thick synthetic gloves that go up sleeves, and those are usually not the kind of gloves that make operating a multimeter very easy. Certainly not that easy that only the knob is touched and never the display. At least that's my experience when I work with electronic equipment and galvanic chemicals at the same time (and yes, that happens. Not the use of a dmm, but the use of specialized rectifiers and other specialized tools)
So I just don't really see the real world scenario that you have in your head.
The chance that the meter falls of a desk or cabinet is much more likely, so impact resistance of the plastic the housing is made of is way more important. So I guess that is why manufacturers test that and give a spec on that, and not it's chemical compatibility to acids.
Besides if these situations occur in a lab, anorganic chemicals that are that potent that they affect plastics, will only be used under a fume hood. If some worker walks away from that still with his gloves on drenched in the stuff to a bench where a dmm is set up, he'll be denying a lot of H&S regulations, risking his co workers way more than a potential DMM. And if the DMM is set up in the fume hood, it becomes a specialized piece of equipment that probably will be tested in advance if it is suitable for that space and there'd be a protocol how to use it.
The most likely situation of a DMM being exposed to a fairly strong acid is I think in a garage, where some amateur is tinkering away with battery acid (37% sulfuric acid) and is getting it over his multimeter. Althoug I don't think it'll attack the PC plastic unless it's a fair amount and left to dry in for days. I imagine the lettering being gone long before that.
Can't fix stupid, can you?
Yes, vehicle workshops are a good place to get your meter in contact with sulphuric acid, also oil, grease, and solvents of various types. The aggressive cellulose thinners aren't used any more afaik, but brake cleaner for example is a great way to ruin your meter casing (don't ask me how I know :palm: ).
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However, this thread was really about the BM789 and it only seems fitting that I show mine. Again, this meter (along with all of my BM78x meters) was provided by Brymen during the development of the meter. This particular one was after the final changes. I have never changed anything with the hardware or touched the alignment.
Yes I saw your video and how fast they fixed that bug you found in the firmware. Very interesting to see them having such a pro-active approach to improve their products.
I'm sure the 78x series will hold up in time just as well as the 86x series and 23x/25x series have. Very well thought out designs and quality materials. On par with Fluke, only for a fraction of the price.
Especially since early this year, Fluke has increased their prices quite a bit here in europe. A BM869S costs €209 (incl tax) with the silicone leads, or more on topic, the BM789 costs €192 with the silicone leads, whereas the Fluke 87V now costs €650 (incl tax) with the crappy pvc leads... :-// :-//
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Someone asked about the Fluke 289's stability. Personally, don't own one but do have a cheap knock off from UNI-T. Current price on Amazon is $400 USD. This meter had the ass blown out of it with my little gas grill igniter (like pretty much every UNI-T product I have looked at). After repairs using OEM parts, I chopped up the PCB. I then exposed the meter to much worse transients. Guessing a brand new one would be as stable (and as easily damaged).
https://www.youtube.com/watch?v=HePnkJuVHuc (https://www.youtube.com/watch?v=HePnkJuVHuc)
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However, this thread was really about the BM789 and it only seems fitting that I show mine. Again, this meter (along with all of my BM78x meters) was provided by Brymen during the development of the meter. This particular one was after the final changes. I have never changed anything with the hardware or touched the alignment.
Yes I saw your video and how fast they fixed that bug you found in the firmware. Very interesting to see them having such a pro-active approach to improve their products.
I'm sure the 78x series will hold up in time just as well as the 86x series and 23x/25x series have. Very well thought out designs and quality materials. On par with Fluke, only for a fraction of the price.
Especially since early this year, Fluke has increased their prices quite a bit here in europe. A BM869S costs €209 (incl tax) with the silicone leads, or more on topic, the BM789 costs €192 with the silicone leads, whereas the Fluke 87V now costs €650 (incl tax) with the crappy pvc leads... :-// :-//
The 87V isn't something I would want for electronics work. I do like the Fluke 187/9 but but that's really the only handheld meter they offered that I like. Just a simple no frills high end meter. I can't argue with how electrically robust all of their products are. Even their lowest end $50 meter is one of the more robust meters I have looked at. Mechanically, I am not so sure. The boot molding on that new 87V I bought looked poor. When the function switch was tested to 50,000 cycles, it sounded like some dying critter and when I inspected it, the contacts were cutting into the PCB. Not at all what I would expect from Fluke.
From my testing, Brymen has proven to be right there with the name brands. Not only some of the most electrically and mechanically robust products on the market but also are withstanding the test of time. Then there is the fact that they actually make products that I have a use for! There is a reason I use the BM869s.
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I have a 121gw serial number 001307 with firmware 2.02 and when reading 500 millivolts from a PDVS2 mini it is perfectly stable and reads 500.00 millivolts exactly.
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My mistake, my 121gw is running firmware 2.05.
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I have a 121gw serial number 001307 with firmware 2.02 and when reading 500 millivolts from a PDVS2 mini it is perfectly stable and reads 500.00 millivolts exactly.
Interesting as mine has a nine digit SN. So I was curious and pulled out the prototype. It also has 9 digits. Wanders about the same. AGAIN TO BE CLEAR, THIS IS A PROTOTYPE AND HAS BEEN HIGHLY MODIFIED TO SURVIVE MY TRANSIENT TESTING!!
The only test equipment running is what is use for the test along with my PC which is maybe a meter away. Both sets of cables were twisted. I added some ferrite to both cables and saw no difference. I did not attempt to shield the 121GW and it's cables. It's certainly possible it is picking something up but odd that all of the other meters tested have been stable. :-//
https://www.youtube.com/watch?v=80HFqz_ukzA (https://www.youtube.com/watch?v=80HFqz_ukzA)
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Someone else with a 121GW would need to look at theirs. Maybe the newer ones are more stable.
Mine is as stable as it an be (one count). Bought in 2021, IIRC.
https://www.youtube.com/watch?v=dAvWWfRkBRo (https://www.youtube.com/watch?v=dAvWWfRkBRo)
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As a metrologist for many years, and have tested/calibrated thousands of meters etc., most calibration labs will test (read "calibrate") the meter using a Fluke 5520 or similar and if it meets spec there will be no further "tweaking" or customer expected calibration. You will receive a data sheet with the actual test results. This is true for a standard cal or 17025 accredited. BTW, my experience purchasing from TME has been super...quicker ship/receive than domestic USA and at a better price.
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Mine is as stable as it an be (one count). Bought in 2021, IIRC.
6 or 9 digit SN? What firmware revision? Thanks.
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Looks like I purchased the two 121GWs from Dave around 11/3/2019. Dave did offer to send me the latest hardware in exchange for these but I figured it had been a few years since I looked at the prototype and to proceed. It's possible that their is a difference in the hardware causing the wandering I am seeing. I can try and add shielding and see if it helps tame it. Way off topic.
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I reviewed the Fluke 289 about a year ago, you can see the stability in my testing:
https://www.youtube.com/watch?v=vr5iVsPCYJk (https://www.youtube.com/watch?v=vr5iVsPCYJk)
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From my testing, Brymen has proven to be right there with the name brands. Not only some of the most electrically and mechanically robust products on the market but also are withstanding the test of time.
As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
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FWIW, I measured 500mV DC with my 121GW (9 digit SN, running FW 2.04) and the reading was stable.
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As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
But we don't have any data for Flukes to compare against.
I've certainly seen plenty of people here showing off about how they just sent their Fluke back and got a new one in exchange.
(but I can buy three Brymens for the same money with 99.9% chance of it lasting longer than me)
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From my testing, Brymen has proven to be right there with the name brands. Not only some of the most electrically and mechanically robust products on the market but also are withstanding the test of time.
As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
No brand has a zero long term failure rate.
But we don't have any data for Flukes to compare against.
I've certainly seen plenty of people here showing off about how they just sent their Fluke back and got a new one in exchange.
(but I can buy three Brymens for the same money with 99.9% chance of it lasting longer than me)
My fluke also stopped working after 1,5 years. It was replaced under warranty no questions asked and has been fine ever since (this was in '09 I believe, the meter is from '07, so almost 15 years ago), so I have lots of confidence in that meter, but I have equal confidence in my Brymen.
For the 300% (if not more) price difference if considered same specs same functionality between Brymen and Fluke, I believe you don't get a better meter.
You only get a lot more mumbojumbo that is only interesting for corporate clients that buy these meters in bulk quantity of 100+
If you're not that kind of client (basically if you have to pay your meters with your own money instead of your shareholders money), imho there's no reason to buy a meter from Fluke nowadays.
2nd hand is a different story (but 2nd hand is a lottery, also pricewise), but with 2nd hand you can also buy some other guy's problems. Certainly if bought unseen and not have been able to open up the meter to inspect it in person. Is this important? Yes as the famous fluke limited lifetime warranty (10 years) or the 1 year warranty on their cheaper lines is not transferrable. So if you buy a used fluke no matter how new, you're out of warranty. This goes for pretty much all brands warranties though
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Mine is as stable as it an be (one count). Bought in 2021, IIRC.
6 or 9 digit SN? What firmware revision? Thanks.
9 digit SN (starting with 210), firmware 2.05. Bought on Amazon US.
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I reviewed the Fluke 289 about a year ago, you can see the stability in my testing:
That stability finding would look good in a report ;)
My meter came with the FlukeView Forms CD software - which worked , or at least uploaded to win7, with the IR version II cable - no joy as yet with win10 [edited, now ok]
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From my testing, Brymen has proven to be right there with the name brands. Not only some of the most electrically and mechanically robust products on the market but also are withstanding the test of time.
As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
Has anyone dug into why their custom silicon suffers these failures? Firmware corruption (I feel if it were this there'd be a lot more cases)? Ionic contamination of the die? Contamination or damage of the die during manufacture? Charge carrier migration or accumulation? It might be nice to have a failed one decapped/X-rayed, to see if there's anything obvious.
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As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
But we don't have any data for Flukes to compare against.
Sure, I'm just saying that problems are certainly there. So don't necessarily expect your Brymen to last 20 years. One of the failure modes seem to be related to some sort of processor die rot.
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Has anyone dug into why their custom silicon suffers these failures? Firmware corruption (I feel if it were this there'd be a lot more cases)? Ionic contamination of the die? Contamination or damage of the die during manufacture? Charge carrier migration or accumulation? It might be nice to have a failed one decapped/X-rayed, to see if there's anything obvious.
We don't know.
BTW, the Brymen processor is not custom, it's a known brand. I'm under NDA so I can't tell you which one.
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As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
No brand has a zero long term failure rate.
Correct.
Just to clarify, "long term" means "didn't fail out of the box". i.e. customer was using it fine and then "something happened". Failures range from just a few months to a few years.
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I have split the 121GW RF thing to another thread:
https://www.eevblog.com/forum/testgear/121gw-rf-issue/ (https://www.eevblog.com/forum/testgear/121gw-rf-issue/)
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As someone who sells a lot of Brymen's, I can attest that they have a noticeable non-zero long term failure rate. It's not high, but it's certainly not zero.
Could you tell us if the failure rate is similar in both models (BM786 and BM235)?
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Yes as the famous fluke limited lifetime warranty (10 years) or the 1 year warranty on their cheaper lines is not transferrable. So if you buy a used fluke no matter how new, you're out of warranty. This goes for pretty much all brands warranties though
A couple of nits to pick here. Fluke's warranty on the industrial line of meters is not 10 years, it is 7 years after the cessation of production or 10 years after purchase, whichever is longer. So if they discontinue the 289 tomorrow, mine (purchased 2010) will have a 20 year warranty. In the US, AFAIK they don't ask for proof of purchase when you send something in, so as long as there isn't something odd about it or someone else already registered it, they just register it in your name and fix it. They also send it back with a new calibration certficate with data if you ask for it.
Also, the warranty on their non-industrial line (11x series, for example) is 3 years, service by replacement only. You probably will get asked for proof of purchase for those models, which makes sense since unlike the industrial line, the warranty could be over even on a current production model.
In the US, if you buy Brymen-branded meters (as opposed to Greenlee) you effectively get no warranty at all. All of these differences may not be enough to justify the huge price differential between the two brands for a lot of users, but the two products are not equivalent as to service and warranty, at least in the US. YMMV and I think the situation is probably almost reversed in the EU.
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rands for a lot of users, but the two products are not equivalent as to service and warranty, at least in the US. YMMV and I think the situation is probably almost reversed in the EU.
My bad, I thought the standard fluke warranty was 1 year, but it is 3 years. But both warranties have written that it's not transferrable. Fluke might not make a problem with that on certain meters, but then you are at the mercy of Fluke and not in your right. Here in Europe, they specifically state in the warranty parameters that the original bill of sale is required to proove you're the original owner.
The LCD has 10 year warranty.
The funny thing is, in the EU the price difference between fluke and Brymen is huge, as fluke products are crazy expensive here. Where you get effectively 2 year warranty on a brymen meter.
So a very basic fluke 115 with 3 years warranty is in the EU considerably more expensive (almost 15%, and you get pvc leads instead of gold plated silicone leads) than the flagship bm869S with 2 year warranty (EU legislation is a bit more complex but the common consensus is that for private persons, the warranty on electronics and household equipment is legally 2 years).
If you go for the higher end fluke meters with similar functionality and specs, the difference is 3 or even 4 fold.
So in the US, fluke might have indeed a better business case regarding warranty and their lower? pricepoint (I'm not 100% up to date on US prices). In the US, you have 1 year warranty on brymen meters afaik, where your point of sale will handle that (so if you bought it in europe, you'll probably have to send it back there). that might be a hassle, no personal experience though.
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https://www.fluke.com/en-us/support/warranties (https://www.fluke.com/en-us/support/warranties)
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Has anyone dug into why their custom silicon suffers these failures? Firmware corruption (I feel if it were this there'd be a lot more cases)? Ionic contamination of the die? Contamination or damage of the die during manufacture? Charge carrier migration or accumulation? It might be nice to have a failed one decapped/X-rayed, to see if there's anything obvious.
We don't know.
BTW, the Brymen processor is not custom, it's a known brand. I'm under NDA so I can't tell you which one.
That just makes me want to see one decapped even more, to search for clues! ;D
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I bought the Bm789, it is quite good. Some photos coming later maybe.
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Some information on BM789.
I am happy with this DMM. There is no competitive product in this price range.
Capacitance is 9999 counts only and not 60 000. You cannot select manual range.
Beeper is more quiet than on BM829s.
Auto V LoZ has no manual range.
Buttons are rather small.
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What's that enormous low resolution meter?
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What's that enormous low resolution meter?
That is a Brymen BM829s bought in 2016. No calibration was done since it was manufactured.
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Brymen BM829s is basically a BM869s with 10000 counts instead of 50000/500000.
I believe it has the exact same set of features. The accuracy specs are a bit relaxed as well (but still 0.08% DCV spec). The cost is significantly less.
Update: there are some minor differences in the feature set of the BM829s:
- 15kHz vs 100kHz bandwidth
- no VFD/low pass filter mode
- no 4-20%mA current loop mode
- adds "AutoCheck"/Lo-Z mode
- adds NVC
Worst of all: the backlight is 30 seconds vs 4 1/2 minutes for BM869s (current shipments)
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Brymens come in a lot of colo(u)rs. I've seen red, blue and green. Are there others?
Putting together a chromatic collection might be a good way to reduce my kid's inheritance. :-DD
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Brymens come in a lot of colo(u)rs. I've seen red, blue and green. Are there others?
Putting together a chromatic collection might be a good way to reduce my kid's inheritance. :-DD
Brymen's own branded meters are red.
Greenlee-branded Brymens are green.
Dave's eevBlog variants are blue.
FLIR's are black.
Evidently Fluke has also rebranded Brymens under both Fluke and Amprobe brands, so I assume they would adopt their standard holster/case colors (yellow and red) but I've not seen one to be sure.
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Evidently Fluke has also rebranded Brymens under both Fluke and Amprobe brands
Which Fluke meter is a Brymen?
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Which Fluke meter is a Brymen?
None are just rebadges where they put a different color holster or case on them, but at least some clamp meters are manufactured by Brymen. The Fluke 373 is one example, although they don't exactly advertise it. It doesn't match up with any Brymen model, but a while back, IIRC floobydust posted some bills of lading from Panjiva or some similar website showing that Brymen was importing "373 Clamp Meter, qty xxx" to Fluke Electronics. Also, TEquipment shows the country of origin to be Taiwan.
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Brymens come in a lot of colo(u)rs. I've seen red, blue and green. Are there others?
Putting together a chromatic collection might be a good way to reduce my kid's inheritance. :-DD
Brymen's own branded meters are red.
Greenlee-branded Brymens are green.
Dave's eevBlog variants are blue.
FLIR's are black.
Evidently Fluke has also rebranded Brymens under both Fluke and Amprobe brands, so I assume they would adopt their standard holster/case colors (yellow and red) but I've not seen one to be sure.
There's orange as well.
https://www.tempocom.com/products/mm810-multimeter/ (https://www.tempocom.com/products/mm810-multimeter/)
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And as bdunham7 pointed out in the "Why do hobbyists buy expensive DMMs" thread (https://www.eevblog.com/forum/beginners/why-do-hobbyists-purchase-the-most-expensive-handheld-dmms/msg5074045/#msg5074045), Fluke still shows up under ImportYeti as a Brymen "top customer":
(https://www.morrisonline.us/images/Screenshot_2023.09.24_11h42m45s_1_Brymen%20Technology%20-%20ImportYeti%20Search%20-%20Google%20Chrome.png)
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Not a Fluke but the Amprobe PM55A pocket meter is a Brymen BM27s.
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As I pointed out in previously, there is no direct proof that Brymen makes any Fluke meters. The far more likely explanation for the documents presented is the fact that Brymen DOES make a few Amprobe clamp meters and both Amprobe and Fluke are owned by Fortive. Also there is Beha-Amprobe which is a wholly owned subsidiary of Fluke and many of the addresses overlap.
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As I pointed out in previously, there is no direct proof that Brymen makes any Fluke meters.
The evidence that Brymen makes the Fluke 373 Clamp Meter is (or was) about as direct as you are going to get. Unfortunately you can't see the bill of lading anymore without an expensive subscription. I may have saved a copy but don't have access at the moment. AFAIK nobody OEMs any of the regular Fluke handheld meters though. Yet.
Edit: Here's a post with an excerpt:
https://www.eevblog.com/forum/repair/dead-brymen-bm869s/msg3606703/#msg3606703 (https://www.eevblog.com/forum/repair/dead-brymen-bm869s/msg3606703/#msg3606703)
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The evidence wasn't direct at all. I looked at the bill of lading myself. There are so many other possible explanations for what was printed on it, the conclusion that Brymen manufactured the Fluke 373 is pretty far down the list.
If you check photos on eBay, you can see that the Fluke 373 meters have "Assembled in China" on the back, not Taiwan.
I honestly don't care if Brymen does make the Fluke 373, but I really think it's important for the health of the forums to be accurate when stating something as fact.
From what makes sense from a manufacturing perspective, it's a bit of a stretch in my mind for Brymen to make something that doesn't line up at all with their existing products. It costs money for tooling and to change gears on the assembly line, so they are going to stick with rebrands.
Fluke also has plenty of manufacturing capabilities, and we know they make some of their products in China, especially the lower-end DMMs.
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The evidence wasn't direct at all. I looked at the bill of lading myself. There are so many other possible explanations for what was printed on it, the conclusion that Brymen manufactured the Fluke 373 is pretty far down the list.
If you check photos on eBay, you can see that the Fluke 373 meters have "Assembled in China" on the back, not Taiwan.
OK, name one reasonable alternative explanation as to why Brymen would ship cartons of a product referred to as "Fluke 373 Digital Multimeters" to Fluke USA and the manual would say "Printed in Taiwan".
The bill of lading was from 2012. If you look you can find some that say "Assembled in China", some that say "Assembled in Taiwan" and a lot that don't say anything. Those markings are on a battery door that is fully removable and fits at least 4 different models. Perhaps some games are being played. Perhaps Brymen assembled some of them in China--many Taiwan companies have operations in mainland China and they surely aren't going to label their stuff there "Taiwan". Perhaps things are different now or perhaps someone is trying to avoid the issue of whether Taiwan is part of China or not, IDK.
But as far as only doing simple rebadges, we know that isn't true. Amprobe and FLIR have products that clearly have significant differences in cases and other things, yet it is pretty clear that they are Brymen derived. Fluke is a big customer and I'm sure Brymen (or any other OEM) wouldn't have a problem with a custom order.
Here is a label from the box of a 2021-model. Short of a clandestine visit to Taipei, IDK what else I can do.
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Here is a label from the box of a 2021-model. Short of a clandestine visit to Taipei, IDK what else I can do.
As far as it actually matters (which is not much), you could disassemble the meter and look at the markings on the PCB, as well as look at the general design and layout of the internal components and any markings on the inside of the case. If an OEM is involved, then they may leave some of their signatures behind during manufacture.
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As far as it actually matters (which is not much), you could disassemble the meter and look at the markings on the PCB, as well as look at the general design and layout of the internal components and any markings on the inside of the case. If an OEM is involved, then they may leave some of their signatures behind during manufacture.
Perhaps, but there are different levels of OEMing. One one hand you may have a company that says to another "we like your product, put our name on it and change the holster to green and we'll retail it". On the other, you may have one that says "here are the design files, can you make it for us exactly as we specify?". So Brymen and Greenlee have one relationship, Apple and Foxconn have another. What Brymen and Fluke have, IDK. I can't find financial information for Brymen, so I've no idea how big a player they actually are, nor who has invested in them.
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I don't know if anyone cares, but here are my notes on some of Brymen's OEM models for Greenlee and Amprobe. Take with a grain of salt - there are likely errors. In fact, if anyone has corrections or additions I'd welcome them. Of course one of the big differences between Greenlee and Brymen (aside from Green vs Red) is the warranty: Greenlee is lifetime, Brymen is typically 1 year (maybe some are 3 years?) and from what I hear is difficult/impossible to get handled if you're in the US.
- Greenlee DM-200A = Brymen BM251 (Greenlee has backlight)
- Greenlee DM-210A = Brymen BM252 (Greenlee has backlight)
- Greenlee DM-510A = Brymen BM257 (Greenlee is still 8A as of Jul 2023, so it's not a BM257s)
- Greenlee DM-820 = Brymen BM859 (note: *not* BM859s)
- Greenlee DM-810A = Brymen BM822s
- Greenlee DM-820A = Brymen BM827s
- Greenlee DM-830A = Brymen BM829s
- Greenlee DML-430A= Brymen BM525s
- Greenlee DM-860 = Brymen BM859s (Extech MM570A)
- Greenlee DM-860A = Brymen BM869s
- Amprobe AM-270 = Brymen BM817a (also identical to BM817s except for fuses and protection rating according to datasheet/manuals)
- Amprobe AM-140-A = BM857a (*very* minor difference in manual range capacitance) and BM857s (except A limited to 15A on AM-140-A, 20A on BM857s), also Extech MM560A. Maybe BM857.
- Amprobe AM-160-A = BM859CFa (*very* minor difference in manual range capacitance) also BM859s. Also Extech MM570A and Greenlee DM860 (not Greenlee DM860A). Maybe BM859.
- Amprobe PM55A = Brymen BM27s
I should also add that the Flir DM64 and DM65 are OEM equivalents of the Brymen DM235 (it seems that the DM64 and DM65 are themselves identical except that the DM65 is packaged with slip-on alligator clips!). Flir's US website is still selling the DM64 for $50 (only shipping to the USA as far as I know). Since the last time I looked at Flir's website the number of multimeters has been reduced significantly. Don't know if that's a temporary thing or the company shifting focus?
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My point of pointing out the Fluke 373 "Assembled in China" was that those weren't made in Taiwan, which was previously presented as proof that they were made by Brymen. Just showing a box label is also not such proof.
So far we've had blatantly obvious proof that Brymen makes such and such products for another company, but proof for Brymen making things for Fluke is not at the same level.
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My point of pointing out the Fluke 373 "Assembled in China" was that those weren't made in Taiwan, which was previously presented as proof that they were made by Brymen. Just showing a box label is also not such proof.
What level of proof you choose to accept is up to you. However, as a geopolitical but topically relevant question, if Brymen assembled the product at their plant in Taipei but shipped some or all of them to Shenzhen (for example)either to be sold in mainland China or to be repackaged and further exported, how would you expect them to be labeled?
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My point of pointing out the Fluke 373 "Assembled in China" was that those weren't made in Taiwan, which was previously presented as proof that they were made by Brymen. Just showing a box label is also not such proof.
So far we've had blatantly obvious proof that Brymen makes such and such products for another company, but proof for Brymen making things for Fluke is not at the same level.
Fluke making their own products in China is not new. It started with the infamous Fluke 19 backin the late 90's as an experiment in the asia-pacific market. And now Fluke make a bunch of lower end and also Asia-specific products in China. I believe it is their own plant, or at least under contract to them. These are all designed by Fluke.
I also have seen zero evidence that Bryman make anything for Fluke.
And AFAIK Brymen do not make anything in China, they are all made in Taiwan.
But yes, some Amprobes are Brymen designs.
I think what's most likely here is that Fluke have independent Chinese and Tawainese assembly houses. After all, if you are designing the meter yourself as Fluke do, then there is no reason to get an established DMM design house to make it for you, can you can use any assembly house. The benefit of going to Brymen is that they have a ready designed and tested product for you.
But maybe Brymen do make it because they already have a relationship through Amprobe?
But a 373 teardown is here. Fluke branded PCB, and looks very Flukey to me. The input ceramic resistor appears to be a Fluke. So appears to be a complete Fluke in-house design.
https://www.youtube.com/watch?v=d1cU42Ns0lk (https://www.youtube.com/watch?v=d1cU42Ns0lk)
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I also have seen zero evidence that Bryman make anything for Fluke.
Brymen just handles the printing, boxing and shipping for them?
https://www.eevblog.com/forum/repair/dead-brymen-bm869s/msg3606703/#msg3606703 (https://www.eevblog.com/forum/repair/dead-brymen-bm869s/msg3606703/#msg3606703)
And AFAIK Brymen do not make anything in China, they are all made in Taiwan.
I think what's most likely here is that Fluke have independent Chinese and Tawainese assembly houses. After all, if you are designing the meter yourself as Fluke do, then there is no reason to get an established DMM design house to make it for you, can you can use any assembly house. The benefit of going to Brymen is that they have a ready designed and tested product for you.
From the website brymen.eu:
"With headquarters located in Taiwan, BRYMEN has subsidiaries in China, America, Japan, Korea and Malaysia; its products are sold to more than 80 countries worldwide."
IDK what that means, but perhaps we don't know all the details behind the Fluke/Brymen interaction. Perhaps they have branched out a bit into custom assembly. Using Brymen would have at least a small advantage in that they are already familiar with the build, testing and quality control of test equipment. AFAIK, Brymen is a privately owned company and finding internal information is impossible, at least for me. Maybe you can go visit them and go rogue on special mission. :)
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I also have seen zero evidence that Bryman make anything for Fluke.
Brymen just handles the printing, boxing and shipping for them?
Maybe. But as I said, design looks to be 100% Fluke.
And what is a 14+ and 15?
(https://www.eevblog.com/forum/repair/dead-brymen-bm869s/?action=dlattach;attach=1235943;image)
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Maybe. But as I said, design looks to be 100% Fluke.
And what is a 14+ and 15?
Absolutely 100% Fluke design and I'd be pretty shocked if it weren't. This works for both parties--if Brymen is contract-locked to someone like Greenlee for Brymen models, presumably that wouldn't apply to a Fluke-designed and exclusive model.
The 14+ and other designations are Amprobe Current Clamp models that don't match any current Brymen models that I could see.
https://www.amprobe.com/product/acd-14-plus/ (https://www.amprobe.com/product/acd-14-plus/)
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Has anyone dug into why their custom silicon suffers these failures? Firmware corruption (I feel if it were this there'd be a lot more cases)? Ionic contamination of the die? Contamination or damage of the die during manufacture? Charge carrier migration or accumulation? It might be nice to have a failed one decapped/X-rayed, to see if there's anything obvious.
We don't know.
BTW, the Brymen processor is not custom, it's a known brand. I'm under NDA so I can't tell you which one.
That just makes me want to see one decapped even more, to search for clues! ;D
But was it the main processor which was failing or the frontend? As far as guessing went, the frontend was supposedly the _Hycon HY3131 or some close modification of it.
I was also mentionig it a few months ago, that it would be unique to see some troubleshooting within a microchip if Dave could arrange it with some labs.
Any clue or guess what chip technology (nm size) these Hycon chips use?
And although off here but is there any statistics anywhere aviable about reliability of microcontrollers? Regarding to manufacturers, nod sizes, etc?
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Has anyone dug into why their custom silicon suffers these failures? Firmware corruption (I feel if it were this there'd be a lot more cases)? Ionic contamination of the die? Contamination or damage of the die during manufacture? Charge carrier migration or accumulation? It might be nice to have a failed one decapped/X-rayed, to see if there's anything obvious.
We don't know.
BTW, the Brymen processor is not custom, it's a known brand. I'm under NDA so I can't tell you which one.
That just makes me want to see one decapped even more, to search for clues! ;D
But was it the main processor which was failing or the frontend?
IIRC Brymen said it was the processor.
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Has anyone dug into why their custom silicon suffers these failures? Firmware corruption (I feel if it were this there'd be a lot more cases)? Ionic contamination of the die? Contamination or damage of the die during manufacture? Charge carrier migration or accumulation? It might be nice to have a failed one decapped/X-rayed, to see if there's anything obvious.
We don't know.
BTW, the Brymen processor is not custom, it's a known brand. I'm under NDA so I can't tell you which one.
That just makes me want to see one decapped even more, to search for clues! ;D
But was it the main processor which was failing or the frontend? As far as guessing went, the frontend was supposedly the _Hycon HY3131 or some close modification of it.
I was also mentionig it a few months ago, that it would be unique to see some troubleshooting within a microchip if Dave could arrange it with some labs.
Any clue or guess what chip technology (nm size) these Hycon chips use?
And although off here but is there any statistics anywhere aviable about reliability of microcontrollers? Regarding to manufacturers, nod sizes, etc?
I'd imagine Dave's NDA would prevent that; Brymen would probably consider such activities a violation of the spirit of it, even if not the exact words.
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Maybe it is not covering the BM235. However, it has another processor....
By the way, new interesting feature of the BM789: In any dc only measuring mode, be it current or voltage, if I turn on the record mode, the display update rate jums up to 9-10/second.
Do other Brymens do this? Yet another Fluke 87V busting feature! :)
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I'd imagine Dave's NDA would prevent that; Brymen would probably consider such activities a violation of the spirit of it, even if not the exact words.
There was a specific NDA for getting the programmer. So I'm not allowed to say processor or programmer is used.
But I don't have a schematic or any other design info.
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By the way, new interesting feature of the BM789: In any dc only measuring mode, be it current or voltage, if I turn on the record mode, the display update rate jums up to 9-10/second.
Do other Brymens do this? Yet another Fluke 87V busting feature! :)
This is documented in the manual.
The following Brymen meters have 20/second update in REC (aka MAX/MIN) mode (not a comprehensive list):
- BM257s
- BM525s
- BM817s (Amprobe AM-270)
The 20/second display update isn't really useful as far as the display goes - if the numbers are changing fast, they're just a blur - better to look at the bargraph. Of course, the important thing is it helps ensure that the meter will catch very short MAX & MIN durations.
Some that do not have faster update in REC mode:
- BM235
- BM857s (Amprobe AM-140-A)
As far as busting the 87V, I'd say "not so fast"! The 87V's default MIN/MAX record rate is 100ms (10/second), just like the BM789. It's just that it doesn't update the digital display any faster (the min/max is taken from the bargraph reading).
Also, the Fluke 87V and many of the Brymens support a "Peak" or "Crest" mode where the min/max is captured for very short transients (0.25ms for the 87V and 0.25ms-5ms for the Brymens depending on the model). In this mode the display doesn't update continuously - it shows the MAX or MIN value (whichever you select)
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The following Brymen meters have 20/second update in REC (aka MAX/MIN) mode (not a comprehensive list):
- BM257s
- BM525s
- BM817s (Amprobe AM-270)
The 20/second display update isn't really useful as far as the display goes - if the numbers are changing fast, they're just a blur - better to look at the bargraph. Of course, the important thing is it helps ensure that the meter will catch very short MAX & MIN durations.
The 10/s update on the BM789's display is not a blur, but "well" readable, so it could be useful sometimes when the baragraphs resolution is not enough.
As far as busting the 87V, I'd say "not so fast"! The 87V's default MIN/MAX record rate is 100ms (10/second), just like the BM789. It's just that it doesn't update the digital display any faster (the min/max is taken from the bargraph reading).
Also, the Fluke 87V and many of the Brymens support a "Peak" or "Crest" mode where the min/max is captured for very short transients (0.25ms for the 87V and 0.25ms-5ms for the Brymens depending on the model). In this mode the display doesn't update continuously - it shows the MAX or MIN value (whichever you select)
The BM789's manual doesnt say anything about the different display update rate, but in REC mode it says the signal duration must be DC 300ms AC 460ms and there is the nominal update rate mentioned, I suppose for the measurement. Because it is 10 for AC but the display stays at 5/sec.
Crest mode says 0,35 ms signal duration. But it goes a bit lower.
JoeQSmith did once a test of the crest modes of some meters, unfotunately the BM789 was not there yet.
It would be a nice test to see how the meters behave with singe glitches, and different signal heights, especially in Amps mode.
But anyway in display update the BM789 beats the Fluke, also in normal mode and in baragraph wiev ;D
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JoeQSmith did once a test of the crest modes of some meters, unfotunately the BM789 was not there yet.
It would be a nice test to see how the meters behave with singe glitches, and different signal heights, especially in Amps mode.
...
I could repeat it with what ever meters I have. I think I had used a constant height and varied the pulse width. Because the meters all work differently, it's a manual process. Adding different signal amplitudes and modes would add a bit of time. Currently my office is a big mess with several projects going on. Maybe once things settle down we can set it up.
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The 10/s update on the BM789's display is not a blur, but "well" readable, so it could be useful sometimes when the baragraphs resolution is not enough.
You're right that the 10/second update isn't too bad. I found the meters with 20/second update were just a blur when things were changing.
The BM789's manual doesnt say anything about the different display update rate, but in REC mode it says the signal duration must be DC 300ms AC 460ms and there is the nominal update rate mentioned, I suppose for the measurement. Because it is 10 for AC but the display stays at 5/sec.
I only verified that the nominal update rate of 10/second in the table for DCV seemed to match up with what I saw and I then assumed that the REC update rates in that table for other modes would match the display updates in REC mode. But I didn't actually test anything other than DCV (in particular the 10/second the table also shows for ACV). Just goes to show that you have to verify everything!
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JoeQSmith did once a test of the crest modes of some meters, unfotunately the BM789 was not there yet.
It would be a nice test to see how the meters behave with singe glitches, and different signal heights, especially in Amps mode.
...
I could repeat it with what ever meters I have. I think I had used a constant height and varied the pulse width. Because the meters all work differently, it's a manual process. Adding different signal amplitudes and modes would add a bit of time. Currently my office is a big mess with several projects going on. Maybe once things settle down we can set it up.
It would be great! Especially to know the blind time of the meters, or if the update rate is really only a few per seconds, so whether glitches close to eachoder pass through without getting catched.
So the waveform update per second basically. :)
I tried to find the mentioned video of yours without luck, can yan you tell which one it was?
I only verified that the nominal update rate of 10/second in the table for DCV seemed to match up with what I saw and I then assumed that the REC update rates in that table for other modes would match the display updates in REC mode. But I didn't actually test anything other than DCV (in particular the 10/second the table also shows for ACV). Just goes to show that you have to verify everything!
If you have an another FW than 08 you could test whether it may gives you 10/sec with AC as well. But I don't think it will. Maybe with a faster changing higher than 50Hz sine wave?
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If you have an another FW than 08 you could test whether it may gives you 10/sec with AC as well. But I don't think it will. Maybe with a faster changing higher than 50Hz sine wave?
Mine (BM786) is also FW 08. I'm sure your observations are correct (also I'm fine with 5/sec update).
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Weeks ago, I contacted Emerson/Greenlee about doing Brymen product service/repair and received no response.
The website can only give you an RMA # from a picklist of valid Greenlee products- so you can't enter anything alien.
Until I hear otherwise, it's a myth you can get Brymen anything in North America - sales and service or calibration.
My theory is they are locked out of the region due to contract with Brymen as an OEM.
1,117kg or 66 cartons is a lot of multimeters per the HTS code, on the container ship One Theseus. It ain't test leads lol.
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JoeQSmith did once a test of the crest modes of some meters, unfotunately the BM789 was not there yet.
It would be a nice test to see how the meters behave with singe glitches, and different signal heights, especially in Amps mode.
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I could repeat it with what ever meters I have. I think I had used a constant height and varied the pulse width. Because the meters all work differently, it's a manual process. Adding different signal amplitudes and modes would add a bit of time. Currently my office is a big mess with several projects going on. Maybe once things settle down we can set it up.
It would be great! Especially to know the blind time of the meters, or if the update rate is really only a few per seconds, so whether glitches close to eachoder pass through without getting catched.
So the waveform update per second basically. :)
I tried to find the mentioned video of yours without luck, can yan you tell which one it was?
I think I have ran it a few times. This was from about 8 years ago with the 87V.
https://youtu.be/UZPjG892C40?t=95
I was firing a one-shot and reducing the duration. The meters have to be reset so I am not sure what you are asking for with the blind time. Personally, I wouldn't have much use for feature. If I am looking at short pulses, I am most likely wanting more detail than what the meters can provide.
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Yes, this was it. Was it really one single pulse, so the scope was just stoped after it? As it seems on the right side of the screen as if another pulse was coming.
You mean by reset, to reset the screen I suppose?
What I meant that if the update rate 10 per sec doesn't mean screen updating, than it could mean that with two short impulses after each other with the second one bigger (so manual screen updating would not be necessary) if it is within 1/10 second of eachother, the second one could pass unnoticed.
I am interested in how rare single glitches might could go unnoticed under certain circumstances.
Or with tricky waveforms.
Like a VFD puts out a single burst of a PWM waveform with only a few squarewaves, which might won't get properly recognized. Or any of the waveforms you tested the RMS funcions with. This is where min/max, crest etc would be used with the meter, especially with higher voltages before getting a scope.
And of course if the 10/sec would be only screen update, maybe later firmwares got it right for AC as well.
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Yes, this was it. Was it really one single pulse, so the scope was just stoped after it? As it seems on the right side of the screen as if another pulse was coming.
You mean by reset, to reset the screen I suppose?
I just watched it and indeed it is live data. For some reason I was thinking it was a one-shot. So, yes it is not a single pulse. Seems the 869s requires you to reset the meter to start a new measurement but maybe not. Again, I own a scope so this isn't something I would normally have a use for.
What I meant that if the update rate 10 per sec doesn't mean screen updating, than it could mean that with two short impulses after each other with the second one bigger (so manual screen updating would not be necessary) if it is within 1/10 second of eachother, the second one could pass unnoticed.
I would imagine some meters have hardware to do the peak detect but maybe not. I dare say the update rate of the CEM is much slower the pulse we are trying to measure.
I am interested in how rare single glitches might could go unnoticed under certain circumstances.
Or with tricky waveforms.
Like a VFD puts out a single burst of a PWM waveform with only a few squarewaves, which might won't get properly recognized. Or any of the waveforms you tested the RMS funcions with. This is where min/max, crest etc would be used with the meter, especially with higher voltages before getting a scope.
And of course if the 10/sec would be only screen update, maybe later firmwares got it right for AC as well.
That's where the scope come into play. Well, for me anyway. That old Fluke scope meter has been nice to have.
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Hi all,
I just received my new BM789 DMM firmware V12.
In regards to the duty cycle function being within the mV setting, what would the upper voltage limit be for taking duty cycle measurements? Could I safely use it with mains voltages? 240VAC
Thanks,
Daniel
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Guessing AI bot but hey, I'll bite. Are you well educated? Skilled electrician? I wouldn't have my sister working on anything mains even with a proper handheld meter.
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To be clear - there is no North American support for these Brymen multimeters such as repair, calibration, firmware updates? It's gotta be shipped trans-ocean for any of that?
correct if you want support you have to buy it under the greenlee brand instead but the prices are MUCH higher that way sometimes double even.
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To be clear - there is no North American support for these Brymen multimeters such as repair, calibration, firmware updates? It's gotta be shipped trans-ocean for any of that?
correct if you want support you have to buy it under the greenlee brand instead but the prices are MUCH higher that way sometimes double even.
I think I'd happily offer a "lifetime" warranty for double the price, or even 50% more.
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Guessing AI bot but hey, I'll bite. Are you well educated? Skilled electrician? I wouldn't have my sister working on anything mains even with a proper handheld meter.
Not AI bot. (Whatever that is in this warped world)
I'm an electronics engineer with audio interest.
I'm asking the above (re: duty cycle measurements) as I had a cheapo dmm that had the duty cycle available in the normal volts range and able to take the measurement at 240vac levels.
But I guess I wouldn't be able to it with the BM789. (OR can I?)
Not willing to damage my meter or test it without a good understanding.
Also, the Brymen manual has bugger all stated in the specs regarding the operational limits of the mV range.
???
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Duty cycle is only specified in the manual for “5V logic”. I don’t think you’ll damage the meter by applying a higher voltage on the mV range, but you’ll get an “overload” reading.
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Ok, thank you.
That makes sense :-+
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[Guessing AI bot but hey, I'll bite. Are you well educated? Skilled electrician? I wouldn't have my sister working on anything mains even with a proper handheld meter.
Not AI bot. (Whatever that is in this warped world)
I'm an electronics engineer with audio interest.
I'm asking the above (re: duty cycle measurements) as I had a cheapo dmm that had the duty cycle available in the normal volts range and able to take the measurement at 240vac levels.
But I guess I wouldn't be able to it with the BM789. (OR can I?)
Not willing to damage my meter or test it without a good understanding.
Also, the Brymen manual has bugger all stated in the specs regarding the operational limits of the mV range.
???
....Could I safely use it with mains voltages? 240VAC
When you asked the above question, you were not referring to your personal safety but rather the meters ability to withstand it. "... and able to take the measurement at 240vac levels"
From that perspective, I did much worse to this meter than what you are proposing and it held up just fine. That said, let me try it tonight and see if I can get a good measurement.
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Being a EE myself, I can't think of one time where I wanted to measure the duty cycle of the mains but what ever floats your boat. Both meters in parallel, 60Hz sinewaveish, 240V. Of course, you follow my videos, you would know this isn't going to pose a problem for this particular meter. Even some of the cheapest ones I look at with their lack of a surge resistor and tiny 5mm PTCs would handle this just fine.
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It is time for a partial teardown of BM789. One screw is missing, but I do not care.
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I've given up all hope of them releasing the Bluetooth version.
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How much memory do they have left?