Brymen BM789 - Page 1
Forum section: electronics / testgear

author: groovesonshunt
author_rank: Contributor
timestamp: January 16, 2023, 06:20:51 pm
content: 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?

author: J-R
author_rank: Super Contributor
timestamp: January 16, 2023, 10:21:05 pm
content: 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.

author: Fungus
author_rank: Super Contributor
timestamp: January 17, 2023, 03:06:12 am
content: Quote from: groovesonshunt on January 16, 2023, 06:20:51 pmAllmeters do that.

author: Neutrion
author_rank: Frequent Contributor
timestamp: January 26, 2023, 02:33:16 pm
content: Also nothing on mine.

author: BillyO
author_rank: Super Contributor
timestamp: January 26, 2023, 03:39:35 pm
content: 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.

author: Fungus
author_rank: Super Contributor
timestamp: January 26, 2023, 03:46:55 pm
content: Quote from: groovesonshunt on January 16, 2023, 06:20:51 pmI thinkallmultimeters do that.AFAICT the stand is there for the viewing angle, not for using it one-handed.

author: Pfriemler
author_rank: Regular Contributor
timestamp: April 25, 2023, 04:44:04 pm
content: Quote from: groovesonshunt on January 16, 2023, 06:20:51 pmI 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.

author: J-R
author_rank: Super Contributor
timestamp: April 25, 2023, 07:20:40 pm
content: Can you post some photos of the areas in which this is not very accurate?

author: Pfriemler
author_rank: Regular Contributor
timestamp: April 26, 2023, 02:14:43 pm
content: 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 voltsMy Brymen BM789 reads2,4999 (+0,01%), 5,002 (+0,02%) in the 6V range and2,500 (+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 ...

author: J-R
author_rank: Super Contributor
timestamp: April 27, 2023, 06:43:23 am
content: 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.

author: Pfriemler
author_rank: Regular Contributor
timestamp: April 27, 2023, 10:47:29 am
content: 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 :-)

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: April 27, 2023, 07:13:55 pm
content: 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.

author: Hydrawerk
author_rank: Super Contributor
timestamp: April 29, 2023, 06:21:09 pm
content: It seems that Brymen BM789 is rebranded as Metrel MD 9055.https://www.metrel.si/en/shop/DMM/digital-multimeters/md-9055.htmlThe picture on website and in the datasheet was probably manipulated... The actual product has 60 000 countsnot duallcd.

author: Hydrawerk
author_rank: Super Contributor
timestamp: April 29, 2023, 06:23:08 pm
content: Actual photos of Metrel MD9055 show the real LCD! It is not a dual readout lcd.

author: Hydrawerk
author_rank: Super Contributor
timestamp: August 05, 2023, 11:44:18 pm
content: 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.

author: Fungus
author_rank: Super Contributor
timestamp: August 05, 2023, 11:49:12 pm
content: Quote from: Hydrawerk on August 05, 2023, 11:44:18 pmNo.(well, there's some other Brymens...and the blue EEVBLOG meter which is a Brymen)Keysight and Fluke are too expensive for me.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.

author: Hydrawerk
author_rank: Super Contributor
timestamp: August 06, 2023, 12:08:18 am
content: Quote from: Fungus on August 05, 2023, 11:49:12 pmOr 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... )

author: EEVblog
author_rank: Unknown
timestamp: August 06, 2023, 02:13:55 am
content: Quote from: Fungus on August 05, 2023, 11:49:12 pm

author: sonpul
author_rank: Regular Contributor
timestamp: August 06, 2023, 07:59:21 am
content: Quote from: Hydrawerk on August 05, 2023, 11:44:18 pmNo. I have not seen another such DMM. Even BM869s I will say No.

author: J-R
author_rank: Super Contributor
timestamp: August 06, 2023, 10:06:03 am
content: Quote from: Hydrawerk on August 05, 2023, 11:44:18 pmThe 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.

author: Fungus
author_rank: Super Contributor
timestamp: August 06, 2023, 11:26:24 am
content: Quote from: Hydrawerk on August 06, 2023, 12:08:18 amIsn't that what I said?Quote from: Hydrawerk on August 06, 2023, 12:08:18 amAre 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.

author: Fungus
author_rank: Super Contributor
timestamp: August 06, 2023, 11:48:54 am
content: Quote from: sonpul on August 06, 2023, 07:59:21 amBM869s 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/#msg4349518To their credit: Brymen was extremely responsive to early testing here on EEVBLOG.

author: EEVblog
author_rank: Unknown
timestamp: August 07, 2023, 12:57:14 am
content: Quote from: Fungus on August 06, 2023, 11:48:54 amThat'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.

author: Fungus
author_rank: Super Contributor
timestamp: August 07, 2023, 01:35:35 am
content: Quote from: EEVblog on August 06, 2023, 02:13:55 amIf 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.

author: floobydust
author_rank: Super Contributor
timestamp: August 07, 2023, 02:09:39 am
content: 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?

author: EEVblog
author_rank: Unknown
timestamp: August 07, 2023, 02:58:22 am
content: Quote from: Fungus on August 07, 2023, 01:35:35 amIt'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 accuracyetc.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.

author: Fungus
author_rank: Super Contributor
timestamp: August 07, 2023, 05:59:21 am
content: Quote from: floobydust on August 07, 2023, 02:09:39 amI'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.

author: EEVblog
author_rank: Unknown
timestamp: August 07, 2023, 06:22:35 am
content: Quote from: Fungus on August 07, 2023, 05:59:21 amCorrect. 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.

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: August 07, 2023, 02:01:10 pm
content: 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.

author: sonpul
author_rank: Regular Contributor
timestamp: August 07, 2023, 02:08:06 pm
content: 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.

author: multiJ
author_rank: Contributor
timestamp: August 08, 2023, 12:47:52 pm
content: 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

author: skander36
author_rank: Frequent Contributor
timestamp: August 08, 2023, 01:06:59 pm
content: Quote from: EEVblog on August 07, 2023, 06:22:35 amless those who make 121GW, although there has been no update lately.

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2023, 01:16:31 pm
content: Quote from: multiJ on August 08, 2023, 12:47:52 pmAlso 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 08, 2023, 01:24:33 pm
content: Quote from: multiJ on August 08, 2023, 12:47:52 pmBM869s 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

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2023, 01:27:24 pm
content: Quote from: joeqsmith on August 08, 2023, 01:24:33 pm"Much"?

author: joeqsmith
author_rank: Super Contributor
timestamp: August 08, 2023, 02:35:57 pm
content: Quote from: Fungus on August 08, 2023, 01:27:24 pmMuch 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.

author: BillyO
author_rank: Super Contributor
timestamp: August 09, 2023, 04:05:11 am
content: 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.

author: EEVblog
author_rank: Unknown
timestamp: August 09, 2023, 05:02:53 am
content: Quote from: multiJ on August 08, 2023, 12:47:52 pmHere you go.

author: EEVblog
author_rank: Unknown
timestamp: August 09, 2023, 05:04:00 am
content: and Fluke 87

author: EEVblog
author_rank: Unknown
timestamp: August 09, 2023, 05:05:05 am
content: And

author: AVGresponding
author_rank: Super Contributor
timestamp: August 09, 2023, 05:16:12 am
content: Quote from: BillyO on August 09, 2023, 04:05:11 amPolycarbonate is much more brittle than polyethylene, which is also highly resistant to acids and solvents.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 09, 2023, 11:35:08 am
content: Quote from: EEVblog on August 09, 2023, 05:02:53 amSomething is missing from the EEVBLOG lineup.

author: EEVblog
author_rank: Unknown
timestamp: August 09, 2023, 12:09:53 pm
content: Quote from: joeqsmith on August 09, 2023, 11:35:08 amThey won't let me sell the 869.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 09, 2023, 12:17:15 pm
content: Quote from: EEVblog on August 09, 2023, 12:09:53 pmThe 869s looks fine in red. Where's the 121?

author: armandine2
author_rank: Frequent Contributor
timestamp: August 09, 2023, 12:23:26 pm
content: Quote from: Fungus on August 08, 2023, 01:16:31 pmor don't have so many to sell?

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2023, 02:00:41 pm
content: Quote from: armandine2 on August 09, 2023, 12:23:26 pmThe Brymen web site shows the 850 series as "professional flagship" and theirnewestmeter is an industrial shape.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 09, 2023, 02:03:27 pm
content: 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.

author: BillyO
author_rank: Super Contributor
timestamp: August 09, 2023, 02:16:43 pm
content: Quote from: AVGresponding on August 09, 2023, 05:16:12 amLOL!Calling polycarbonate brittle is like calling copper highly resistive.Things made with PE:sandwich bagsfreezer bagsvapor barrierfood containersFluke metersThings made with PC:Bullet proof face shieldsmotocross goggle lensesmotorcycle helmetsexplosion proof cabinetsBrymen meters

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2023, 02:41:49 pm
content: Quote from: BillyO on August 09, 2023, 02:16:43 pmCopperisresistive compared to silver.

author: BillyO
author_rank: Super Contributor
timestamp: August 09, 2023, 02:52:13 pm
content: Quote from: Fungus on August 09, 2023, 02:41:49 pmMy point exactly.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 09, 2023, 03:04:52 pm
content: 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.)

author: AVGresponding
author_rank: Super Contributor
timestamp: August 09, 2023, 04:43:38 pm
content: Quote from: BillyO on August 09, 2023, 02:16:43 pmQuote from: Doctorandus_P on August 09, 2023, 03:04:52 pmI 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.

author: mwb1100
author_rank: Frequent Contributor
timestamp: August 09, 2023, 05:59:56 pm
content: Quote from: Doctorandus_P on August 09, 2023, 02:03:27 pmThe Fluke 87v has that feature (but not every Fluke model does - I'm pretty sure the same is true for Brymen)

author: sonpul
author_rank: Regular Contributor
timestamp: August 09, 2023, 07:05:05 pm
content: Brymen copied the AutoHold feature from Fluke and the BM78x are the only ones with it.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 09, 2023, 07:06:29 pm
content: Quote from: mwb1100 on August 09, 2023, 05:59:56 pmBrymen 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, BM231https://brymen.eu/wp-content/uploads/biall/102173/102173.KARTA_EN..2016-09-30.1.pdfBM257, BM255, BM252, BM251https://brymen.eu/wp-content/uploads/biall/102085/102085.KARTA_EN..2022-05-17.2.pdfBM789, BM785https://brymen.eu/wp-content/uploads/biall/102222/102222.KARTA_EN..2020-10-26.1.pdfBM807, BM806, BM805https://brymen.eu/wp-content/uploads/biall/102027/102027.KARTA_EN..2015-07-21.1.pdfBM867s, BM869shttps://brymen.eu/wp-content/uploads/biall/102092/102092.INSTRUKCJA_EN..2014-11-04.1.pdfBM878, BM877, BM876https://brymen.eu/wp-content/uploads/biall/102133/102133.KARTA_EN..2015-07-09.1.pdfBM905s, BM906s, BM907Shttps://brymen.eu/wp-content/uploads/biall/102114/102114.INSTRUKCJA_EN..2014-11-04.1.pdfI did not check pocket meters and clamp meters. They don't have it of course because they do not have an Amp input.

author: EEVblog
author_rank: Unknown
timestamp: August 09, 2023, 09:29:47 pm
content: Quote from: Doctorandus_P on August 09, 2023, 02:03:27 pmFor the few people that haven't seen it:

author: Martin72
author_rank: Super Contributor
timestamp: August 09, 2023, 09:48:39 pm
content: QuoteWell, 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...

author: Fungus
author_rank: Super Contributor
timestamp: August 09, 2023, 11:17:56 pm
content: Quote from: Doctorandus_P on August 09, 2023, 02:03:27 pmI wouldn't buy a "serious" meter without it.Quote from: mwb1100 on August 09, 2023, 05:59:56 pmAll Brymens have it AFAIK.(apart from their pocket meter)

author: EEVblog
author_rank: Unknown
timestamp: August 09, 2023, 11:21:41 pm
content: Quote from: joeqsmith on August 09, 2023, 12:17:15 pmHere 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.

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: August 10, 2023, 12:20:58 am
content: 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 batteriesFluke 179: 405g, 43mmBremen 756: 419g, 51mmFluke 87v: 508g, 52mmBremen 869s: 627g, 64.5mmI 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.

author: BillyO
author_rank: Super Contributor
timestamp: August 10, 2023, 02:39:50 am
content: Quote from: AVGresponding on August 09, 2023, 04:43:38 pmLots 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.

author: EEVblog
author_rank: Unknown
timestamp: August 10, 2023, 03:10:40 am
content: Quote from: NoisyBoy on August 10, 2023, 12:20:58 amI 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.

author: multiJ
author_rank: Contributor
timestamp: August 10, 2023, 04:48:21 am
content: Quote from: Martin72 on August 09, 2023, 09:48:39 pmAre 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

author: J-R
author_rank: Super Contributor
timestamp: August 10, 2023, 05:47:57 am
content: 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/Fortunately the calibration/adjustment procedure for the BM869 is well known and easy to perform:https://www.jackenhack.com/calibrating-brymen-bm-series-multimeter/If you calibrate/adjust the 500,000 count modes, you won't be disappointed.

author: AVGresponding
author_rank: Super Contributor
timestamp: August 10, 2023, 08:55:15 am
content: Quote from: EEVblog on August 10, 2023, 03:10:40 amBecause 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.

author: EEVblog
author_rank: Unknown
timestamp: August 10, 2023, 09:35:05 am
content: Quote from: AVGresponding on August 10, 2023, 08:55:15 amThere is the Kane 555:http://cn.kanetest.co.kr/shop.php?goPage=GoodDetail&g_code=20220330171318692&cat_no=2Basically 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.htmlSmaller in all dimentions, weighs less at 570gOr one of the Gossens maybe, but IIRC they won't be any smaller.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 10, 2023, 10:54:56 am
content: Quote from: EEVblog on August 10, 2023, 09:35:05 amFrom what I remember, the zener mode made it difficult to protect the meter from transients. Maybe the 555 is more robust.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 10, 2023, 11:23:08 am
content: Quote from: J-R on August 10, 2023, 05:47:57 amI 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.

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 10, 2023, 11:25:39 am
content: Quote from: EEVblog on August 10, 2023, 03:10:40 amI 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.

author: EEVblog
author_rank: Unknown
timestamp: August 10, 2023, 11:59:52 am
content: Quote from: BeBuLamar on August 10, 2023, 11:25:39 amWell, itwaswhen it was first introduced35 years ago

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 10, 2023, 12:38:28 pm
content: Quote from: EEVblog on August 10, 2023, 11:59:52 amAlthough it's capable of 20,000 count meter it's basically a 6,000 meter.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 10, 2023, 02:23:16 pm
content: 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.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).

author: AVGresponding
author_rank: Super Contributor
timestamp: August 10, 2023, 05:00:52 pm
content: Quote from: EEVblog on August 10, 2023, 09:35:05 amI 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 arealldead, I'm not really in the market for a new work meter...Quote from: BillyO on August 10, 2023, 02:39:50 amI'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?

author: J-R
author_rank: Super Contributor
timestamp: August 10, 2023, 06:36:07 pm
content: For checking DCV accuracy on the BM869 it would be best to test at 5V and using 500,000 count mode.

author: Martin72
author_rank: Super Contributor
timestamp: August 10, 2023, 08:48:40 pm
content: Hi,Quote from: multiJ on August 10, 2023, 04:48:21 amMaybe 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.QuoteWelectron 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-CalibrationI think this service is good, as a private person you usually can't get it so easily.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 10, 2023, 09:04:22 pm
content: Quote from: J-R on August 10, 2023, 06:36:07 pmAgain, 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.

author: J-R
author_rank: Super Contributor
timestamp: August 10, 2023, 10:29:46 pm
content: Quote from: joeqsmith on August 10, 2023, 09:04:22 pmFair 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.

author: AVGresponding
author_rank: Super Contributor
timestamp: August 10, 2023, 10:34:54 pm
content: Quote from: J-R on August 10, 2023, 06:36:07 pmfwiw (not much) my 869S, which has had ahardlife, agrees with my (relatively recently) calibrated Fluke 8840A to within around a millivolt or so, with a 5 volt source applied.

author: BeBuLamar
author_rank: Super Contributor
timestamp: August 10, 2023, 10:51:15 pm
content: 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.

author: Fungus
author_rank: Super Contributor
timestamp: August 10, 2023, 11:24:17 pm
content: Quote from: Martin72 on August 10, 2023, 08:48:40 pmSeems that way.Mine is about 5 years old now and either hasn't drifted at all or has drifted atexactlythe same rate as my other meters and voltage reverences (which would be too big a coincidence to believe...)

author: J-R
author_rank: Super Contributor
timestamp: August 10, 2023, 11:30:38 pm
content: 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.

author: J-R
author_rank: Super Contributor
timestamp: August 10, 2023, 11:41:37 pm
content: Quote from: AVGresponding on August 10, 2023, 10:34:54 pmThat 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 10, 2023, 11:47:32 pm
content: Quote from: J-R on August 10, 2023, 10:29:46 pmI 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.

author: Veteran68
author_rank: Frequent Contributor
timestamp: August 11, 2023, 01:13:57 pm
content: Quote from: BeBuLamar on August 10, 2023, 10:51:15 pmOther 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.

author: Electro Fan
author_rank: Super Contributor
timestamp: August 11, 2023, 02:33:13 pm
content: Quote from: Veteran68 on August 11, 2023, 01:13:57 pm+1 on 789 from Europe

author: mwb1100
author_rank: Frequent Contributor
timestamp: August 11, 2023, 04:16:13 pm
content: Quote from: Veteran68 on August 11, 2023, 01:13:57 pmWhen 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).

author: Martin72
author_rank: Super Contributor
timestamp: August 11, 2023, 08:48:30 pm
content: Try "marcoreps5" for the coupon code (5%).Edit: Pic.

author: Hydrawerk
author_rank: Super Contributor
timestamp: August 27, 2023, 04:13:11 pm
content: 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

author: joeqsmith
author_rank: Super Contributor
timestamp: August 27, 2023, 05:20:43 pm
content: Quote from: joeqsmith on August 10, 2023, 11:47:32 pmBut 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.Still my favorite meter.

author: mwb1100
author_rank: Frequent Contributor
timestamp: August 27, 2023, 08:00:20 pm
content: Quote from: Hydrawerk on August 27, 2023, 04:13:11 pmOne 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):QuoteInstead get the BM786 or BM789 for under 200 EUR (often far less). Great meters - especially for the price.

author: J-R
author_rank: Super Contributor
timestamp: August 27, 2023, 11:01:14 pm
content: - 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 28, 2023, 12:00:57 am
content: QuoteThe 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 28, 2023, 10:34:39 am
content: Quote from: J-R on August 27, 2023, 11:01:14 pmI 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 28, 2023, 11:51:47 am
content: https://voltagestandard.com/01%25-voltage-referencesQuoteMy 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=1691065892806Just 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.

author: EEVblog
author_rank: Unknown
timestamp: August 28, 2023, 10:23:18 pm
content: Quote from: mwb1100 on August 27, 2023, 08:00:20 pmThe BM786 is exclusive to me.

author: J-R
author_rank: Super Contributor
timestamp: August 29, 2023, 05:07:36 am
content: 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:5.00009V5.00012V5.00013V(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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 29, 2023, 08:43:14 am
content: QuoteIt 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.QuoteHard 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.

author: J-R
author_rank: Super Contributor
timestamp: August 30, 2023, 09:30:06 am
content: 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-referenceActually 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 30, 2023, 12:32:41 pm
content: Quote from: J-R on August 30, 2023, 09:30:06 amAs 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.

author: NoisyBoy
author_rank: Frequent Contributor
timestamp: August 30, 2023, 04:38:38 pm
content: 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 30, 2023, 10:37:48 pm
content: Quote from: NoisyBoy on August 30, 2023, 04:38:38 pmIn my house, in a spare room. It's not a business.QuoteMy 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.

author: J-R
author_rank: Super Contributor
timestamp: August 31, 2023, 05:06:49 am
content: 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 31, 2023, 01:40:54 pm
content: Quote from: J-R on August 31, 2023, 05:06:49 amIt 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.

author: Veteran68
author_rank: Frequent Contributor
timestamp: August 31, 2023, 02:04:30 pm
content: Quote from: joeqsmith on August 31, 2023, 01:40:54 pmWhen 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 31, 2023, 03:46:19 pm
content: 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.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.

author: GuidoK
author_rank: Regular Contributor
timestamp: September 01, 2023, 11:51:07 pm
content: Quote from: AVGresponding on August 09, 2023, 04:43:38 pmYou 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.

author: GuidoK
author_rank: Regular Contributor
timestamp: September 02, 2023, 12:12:44 am
content: Quote from: Martin72 on August 10, 2023, 08:48:40 pmI 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 accurateAll 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.

author: GuidoK
author_rank: Regular Contributor
timestamp: September 02, 2023, 12:26:35 am
content: Quote from: EEVblog on August 07, 2023, 12:57:14 amThe 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 02:10:05 am
content: QuoteGood 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 +120uVAgain, 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 02:26:56 am
content: 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.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.

author: AVGresponding
author_rank: Super Contributor
timestamp: September 02, 2023, 05:28:43 am
content: Quote from: GuidoK on September 01, 2023, 11:51:07 pmIf 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.

author: GuidoK
author_rank: Regular Contributor
timestamp: September 02, 2023, 07:06:45 am
content: Quote from: AVGresponding on September 02, 2023, 05:28:43 amHow 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.

author: AVGresponding
author_rank: Super Contributor
timestamp: September 02, 2023, 11:25:40 am
content: Quote from: GuidoK on September 02, 2023, 07:06:45 amThat'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.

author: GuidoK
author_rank: Regular Contributor
timestamp: September 02, 2023, 12:37:31 pm
content: 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?

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 01:45:38 pm
content: 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??

author: GuidoK
author_rank: Regular Contributor
timestamp: September 02, 2023, 03:31:36 pm
content: Quote from: joeqsmith on September 02, 2023, 01:45:38 pmWow 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 lineAnd 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!

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 04:25:35 pm
content: 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.

author: AVGresponding
author_rank: Super Contributor
timestamp: September 02, 2023, 04:41:34 pm
content: Quote from: GuidoK on September 02, 2023, 12:37:31 pmYes, 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).

author: GuidoK
author_rank: Regular Contributor
timestamp: September 02, 2023, 06:33:41 pm
content: Quote from: joeqsmith on September 02, 2023, 04:25:35 pmYes 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...

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 06:36:55 pm
content: 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).

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 07:02:12 pm
content: Quote from: GuidoK on September 02, 2023, 06:33:41 pmThe 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.

author: dseyst
author_rank: Contributor
timestamp: September 02, 2023, 08:13:21 pm
content: 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.

author: dseyst
author_rank: Contributor
timestamp: September 02, 2023, 08:48:31 pm
content: My mistake, my 121gw is running firmware 2.05.

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 08:49:39 pm
content: Quote from: dseyst on September 02, 2023, 08:13:21 pmInteresting 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.

author: Caliaxy
author_rank: Frequent Contributor
timestamp: September 02, 2023, 09:02:06 pm
content: Quote from: joeqsmith on September 02, 2023, 04:25:35 pmMine is as stable as it an be (one count). Bought in 2021, IIRC.

author: amham
author_rank: Newbie
timestamp: September 02, 2023, 09:14:15 pm
content: 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: September 02, 2023, 11:19:39 pm
content: Quote from: Caliaxy on September 02, 2023, 09:02:06 pm6 or 9 digit SN? What firmware revision? Thanks.***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.

author: TheDefpom
author_rank: Frequent Contributor
timestamp: September 03, 2023, 01:59:25 am
content: I reviewed the Fluke 289 about a year ago, you can see the stability in my testing:

author: EEVblog
author_rank: Unknown
timestamp: September 03, 2023, 11:25:03 am
content: Quote from: joeqsmith on September 02, 2023, 07:02:12 pmAs 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.

author: giosif
author_rank: Frequent Contributor
timestamp: September 03, 2023, 11:38:51 am
content: FWIW, I measured 500mV DC with my 121GW (9 digit SN, running FW 2.04) and the reading was stable.

author: Fungus
author_rank: Super Contributor
timestamp: September 03, 2023, 11:50:09 am
content: Quote from: EEVblog on September 03, 2023, 11:25:03 amBut 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)

author: GuidoK
author_rank: Regular Contributor
timestamp: September 03, 2023, 11:57:09 am
content: Quote from: EEVblog on September 03, 2023, 11:25:03 amNo brand has a zero long term failure rate.Quote from: Fungus on September 03, 2023, 11:50:09 amMy 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

author: Caliaxy
author_rank: Frequent Contributor
timestamp: September 03, 2023, 12:15:08 pm
content: Quote from: joeqsmith on September 02, 2023, 11:19:39 pm9 digit SN (starting with 210), firmware 2.05. Bought on Amazon US.

author: armandine2
author_rank: Frequent Contributor
timestamp: September 03, 2023, 02:50:15 pm
content: Quote from: TheDefpom on September 03, 2023, 01:59:25 amThat stability finding would look good in a reportMy 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]

author: AVGresponding
author_rank: Super Contributor
timestamp: September 03, 2023, 03:09:41 pm
content: Quote from: EEVblog on September 03, 2023, 11:25:03 amHas 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.

author: EEVblog
author_rank: Unknown
timestamp: September 03, 2023, 11:10:56 pm
content: Quote from: Fungus on September 03, 2023, 11:50:09 amSure, 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.

author: EEVblog
author_rank: Unknown
timestamp: September 03, 2023, 11:12:43 pm
content: Quote from: AVGresponding on September 03, 2023, 03:09:41 pmWe 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.

author: EEVblog
author_rank: Unknown
timestamp: September 03, 2023, 11:17:49 pm
content: Quote from: GuidoK on September 03, 2023, 11:57:09 amCorrect.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.

author: EEVblog
author_rank: Unknown
timestamp: September 04, 2023, 05:32:59 am
content: I have split the 121GW RF thing to another thread:https://www.eevblog.com/forum/testgear/121gw-rf-issue/

author: Caliaxy
author_rank: Frequent Contributor
timestamp: September 04, 2023, 03:26:12 pm
content: Quote from: EEVblog on September 03, 2023, 11:25:03 amCould you tell us if the failure rate is similar in both models (BM786 and BM235)?

author: bdunham7
author_rank: Super Contributor
timestamp: September 04, 2023, 03:28:22 pm
content: Quote from: GuidoK on September 03, 2023, 11:57:09 amA 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.

author: GuidoK
author_rank: Regular Contributor
timestamp: September 04, 2023, 06:30:15 pm
content: Quote from: bdunham7 on September 04, 2023, 03:28:22 pmMy 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.

author: Electro Fan
author_rank: Super Contributor
timestamp: September 04, 2023, 08:00:15 pm
content: https://www.fluke.com/en-us/support/warranties

author: AVGresponding
author_rank: Super Contributor
timestamp: September 05, 2023, 04:50:36 am
content: Quote from: EEVblog on September 03, 2023, 11:12:43 pmThat just makes me want to see one decapped even more, to search for clues!

author: Hydrawerk
author_rank: Super Contributor
timestamp: September 16, 2023, 04:54:33 pm
content: I bought the Bm789, it is quite good. Some photos coming later maybe.

author: Hydrawerk
author_rank: Super Contributor
timestamp: September 23, 2023, 11:18:22 pm
content: 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.

author: BillyO
author_rank: Super Contributor
timestamp: September 23, 2023, 11:22:16 pm
content: What's that enormous low resolution meter?

author: Hydrawerk
author_rank: Super Contributor
timestamp: September 23, 2023, 11:33:19 pm
content: Quote from: BillyO on September 23, 2023, 11:22:16 pmThat is a Brymen BM829s bought in 2016. No calibration was done since it was manufactured.

author: mwb1100
author_rank: Frequent Contributor
timestamp: September 23, 2023, 11:53:16 pm
content: 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 NVCWorst of all: the backlight is 30 seconds vs 4 1/2 minutes for BM869s (current shipments)

author: BillyO
author_rank: Super Contributor
timestamp: September 24, 2023, 12:11:52 am
content: 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.

author: Veteran68
author_rank: Frequent Contributor
timestamp: September 24, 2023, 03:25:09 am
content: Quote from: BillyO on September 24, 2023, 12:11:52 amBrymen'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.

author: EEVblog
author_rank: Unknown
timestamp: September 24, 2023, 05:46:36 am
content: Quote from: Veteran68 on September 24, 2023, 03:25:09 amWhich Fluke meter is a Brymen?

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 03:37:49 pm
content: Quote from: EEVblog on September 24, 2023, 05:46:36 amNone 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, IIRCfloobydustposted 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.

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 03:40:03 pm
content: Quote from: Veteran68 on September 24, 2023, 03:25:09 amThere's orange as well.https://www.tempocom.com/products/mm810-multimeter/

author: Veteran68
author_rank: Frequent Contributor
timestamp: September 24, 2023, 03:48:46 pm
content: And as bdunham7pointed out in the "Why do hobbyists buy expensive DMMs" thread, Fluke still shows up under ImportYeti as a Brymen "top customer":

author: joeqsmith
author_rank: Super Contributor
timestamp: September 24, 2023, 04:42:53 pm
content: Not a Fluke but the Amprobe PM55A pocket meter is a Brymen BM27s.

author: J-R
author_rank: Super Contributor
timestamp: September 24, 2023, 05:17:07 pm
content: 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.

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 05:41:40 pm
content: Quote from: J-R on September 24, 2023, 05:17:07 pmThe 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

author: J-R
author_rank: Super Contributor
timestamp: September 24, 2023, 06:15:58 pm
content: 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.

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 06:51:02 pm
content: Quote from: J-R on September 24, 2023, 06:15:58 pmOK, 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.

author: IanB
author_rank: Super Contributor
timestamp: September 24, 2023, 07:13:00 pm
content: Quote from: bdunham7 on September 24, 2023, 06:51:02 pmAs 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.

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 07:34:56 pm
content: Quote from: IanB on September 24, 2023, 07:13:00 pmPerhaps, 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.

author: mwb1100
author_rank: Frequent Contributor
timestamp: September 24, 2023, 07:36:19 pm
content: 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 BM27sI 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?

author: J-R
author_rank: Super Contributor
timestamp: September 24, 2023, 08:25:43 pm
content: 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.

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 08:46:57 pm
content: Quote from: J-R on September 24, 2023, 08:25:43 pmWhat 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?

author: EEVblog
author_rank: Unknown
timestamp: September 24, 2023, 10:58:54 pm
content: Quote from: J-R on September 24, 2023, 08:25:43 pmFluke 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.

author: bdunham7
author_rank: Super Contributor
timestamp: September 24, 2023, 11:27:54 pm
content: Quote from: EEVblog on September 24, 2023, 10:58:54 pmBrymen just handles the printing, boxing and shipping for them?https://www.eevblog.com/forum/repair/dead-brymen-bm869s/msg3606703/#msg3606703QuoteFrom 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.

author: EEVblog
author_rank: Unknown
timestamp: September 25, 2023, 01:25:31 am
content: Quote from: bdunham7 on September 24, 2023, 11:27:54 pmMaybe. But as I said, design looks to be 100% Fluke.And what is a 14+ and 15?

author: bdunham7
author_rank: Super Contributor
timestamp: September 25, 2023, 01:34:54 am
content: Quote from: EEVblog on September 25, 2023, 01:25:31 amAbsolutely 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/

author: Neutrion
author_rank: Frequent Contributor
timestamp: September 27, 2023, 05:47:03 pm
content: Quote from: AVGresponding on September 05, 2023, 04:50:36 amBut 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?

author: EEVblog
author_rank: Unknown
timestamp: September 28, 2023, 12:26:09 am
content: Quote from: Neutrion on September 27, 2023, 05:47:03 pmIIRC Brymen said it was the processor.

author: AVGresponding
author_rank: Super Contributor
timestamp: September 28, 2023, 05:25:26 am
content: Quote from: Neutrion on September 27, 2023, 05:47:03 pmI'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.

author: Neutrion
author_rank: Frequent Contributor
timestamp: September 28, 2023, 10:33:34 am
content: 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!

author: EEVblog
author_rank: Unknown
timestamp: September 29, 2023, 07:06:49 am
content: Quote from: AVGresponding on September 28, 2023, 05:25:26 amThere 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.

author: mwb1100
author_rank: Frequent Contributor
timestamp: September 29, 2023, 08:30:08 am
content: Quote from: Neutrion on September 28, 2023, 10:33:34 amThis 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)

author: Neutrion
author_rank: Frequent Contributor
timestamp: September 29, 2023, 10:14:24 am
content: Quote from: mwb1100 on September 29, 2023, 08:30:08 amThe 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.Quote from: mwb1100 on September 29, 2023, 08:30:08 amThe 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

author: joeqsmith
author_rank: Super Contributor
timestamp: September 29, 2023, 01:52:02 pm
content: Quote from: Neutrion on September 29, 2023, 10:14:24 amI 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.

author: mwb1100
author_rank: Frequent Contributor
timestamp: September 29, 2023, 05:03:28 pm
content: Quote from: Neutrion on September 29, 2023, 10:14:24 amYou'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.Quote from: Neutrion on September 29, 2023, 10:14:24 amI 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!

author: Neutrion
author_rank: Frequent Contributor
timestamp: September 30, 2023, 01:23:05 pm
content: Quote from: joeqsmith on September 29, 2023, 01:52:02 pmIt 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?Quote from: mwb1100 on September 29, 2023, 05:03:28 pmIf 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?

author: mwb1100
author_rank: Frequent Contributor
timestamp: September 30, 2023, 07:38:05 pm
content: Quote from: Neutrion on September 30, 2023, 01:23:05 pmMine (BM786) is also FW 08. I'm sure your observations are correct (also I'm fine with 5/sec update).

author: floobydust
author_rank: Super Contributor
timestamp: October 01, 2023, 07:28:39 pm
content: 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: October 01, 2023, 08:08:06 pm
content: Quote from: Neutrion on September 30, 2023, 01:23:05 pmI think I have ran it a few times. This was from about 8 years ago with the 87V.https://youtu.be/UZPjG892C40?t=95I 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.

author: Neutrion
author_rank: Frequent Contributor
timestamp: October 03, 2023, 02:16:16 pm
content: 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: October 03, 2023, 02:46:24 pm
content: Quote from: Neutrion on October 03, 2023, 02:16:16 pmI 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.Quote from: Neutrion on October 03, 2023, 02:16:16 pmI 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.Quote from: Neutrion on October 03, 2023, 02:16:16 pmThat's where the scope come into play. Well, for me anyway. That old Fluke scope meter has been nice to have.

author: TDA1541AS2
author_rank: Newbie
timestamp: October 06, 2023, 12:55:12 pm
content: 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? 240VACThanks,Daniel

author: joeqsmith
author_rank: Super Contributor
timestamp: October 06, 2023, 01:02:22 pm
content: 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.

author: mastershake
author_rank: Frequent Contributor
timestamp: October 08, 2023, 11:46:54 pm
content: Quote from: floobydust on August 07, 2023, 02:09:39 amcorrect 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.

author: EEVblog
author_rank: Unknown
timestamp: October 09, 2023, 01:13:23 am
content: Quote from: mastershake on October 08, 2023, 11:46:54 pmI think I'd happily offer a "lifetime" warranty for double the price, or even 50% more.

author: TDA1541AS2
author_rank: Newbie
timestamp: October 09, 2023, 01:30:05 pm
content: [Quote from: joeqsmith on October 06, 2023, 01:02:22 pmNot 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.

author: Caliaxy
author_rank: Frequent Contributor
timestamp: October 09, 2023, 02:06:17 pm
content: 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.

author: TDA1541AS2
author_rank: Newbie
timestamp: October 09, 2023, 02:16:54 pm
content: Ok, thank you.That makes sense

author: joeqsmith
author_rank: Super Contributor
timestamp: October 09, 2023, 07:27:57 pm
content: Quote from: TDA1541AS2 on October 09, 2023, 01:30:05 pmQuote from: TDA1541AS2 on October 06, 2023, 12:55:12 pmWhen 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.

author: joeqsmith
author_rank: Super Contributor
timestamp: October 09, 2023, 10:52:54 pm
content: 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.

author: Hydrawerk
author_rank: Super Contributor
timestamp: October 29, 2023, 10:54:49 pm
content: It is time for a partial teardown of BM789. One screw is missing, but I do not care.

author: EEVblog
author_rank: Unknown
timestamp: October 29, 2023, 11:15:22 pm
content: I've given up all hope of them releasing the Bluetooth version.

author: floobydust
author_rank: Super Contributor
timestamp: October 30, 2023, 03:41:47 am
content: How much memory do they have left?

author: Astray
author_rank: Contributor
timestamp: June 23, 2024, 01:02:03 pm
content: Curious, does anyone know if there's an accessory that would allow me to use a BM786 or BM789 similar to a clamping multimeter?I understand there's an Electrical Field detection feature already available but it would be nice if there was a clamp I could attach to the multimeter's inputs to have it estimate the current in a wire, instead of buying a whole new multimeter just for the clamping function.

author: BILLPOD
author_rank: Frequent Contributor
timestamp: June 23, 2024, 01:39:39 pm
content: if there was a clamp I could attach to the multimeter's inputs to have it estimate the current in a wire, instead of buying a whole new multimeter just for the clamping function.AliExpress sells a clamp accessory for their UT117C meter. It is modelUT-CS05A and is supposedly good for 400A of AC current. I have tried it on other meters I have with a mV range and it works for me, although I haven't tried it it on over 8 Amps. Also, for me it wouldn't register anything under 1.5 A. It was only a $20 accessory from Aliexpress.

author: TomKatt
author_rank: Frequent Contributor
timestamp: June 23, 2024, 03:36:18 pm
content: Quote from: Astray on June 23, 2024, 01:02:03 pmThere are many current clamps available for multimeters - I’ve got an Amprobe 237 that measures AC/DC 20A / 200A that works pretty well. It scales amps to mV so you read the voltage that represents the current. Works well and has safety banana plugs that fit into the multimeter. If I need super accurate measurements for lower current I just use the multimeter current feature.On topic, I’ve got a Greenlee DM820A which is a Brymen rebadge - I think the equivalent Brymen model is am 867s. As good as the Flukes the maintenance guys have at my shop. Lucked out on eBay and got it for $50 with carry bag and accessories. Makes a great companion for my BM235 I got here - I love the flashing continuity display on the 235.

author: joeqsmith
author_rank: Super Contributor
timestamp: June 23, 2024, 06:12:59 pm
content: Quote from: Astray on June 23, 2024, 01:02:03 pmWhile you don't provide any specific requirements beyond it having to be a clamp, I bought one of these new when Radio Shack was still around.https://www.ebay.com/p/1022934766

author: joeqsmith
author_rank: Super Contributor
timestamp: June 23, 2024, 07:49:33 pm
content: Showing the Radio Shack clamp attached to the BM789. I bought a Kline tools PN 69409 line splitter for a debunk video I made. I am using the 10X side of the splitter.First I tried it with a simple light bulb. The Kill-A-Watt EZ measures 0.48A. This is a standard filament bulb so PF=1. The BM789 measures 2.172mA. The probe is 1mA = 2A. So 2.172*2/10X = 434.4mANext I tried it with my heat gun. Again, it's a resistive load so the power factor is one. The Kill-A-Watt EZ measures 3.72 Amps. The BM789 measures 17.447mA. Again 17.447 * 2/10 = 3.4894A.I'm not sure how accurate the Kill A Watt, meter or probe are. The probe is +/-0.6A at 50/60Hz for 1-2A. They show no data below 1A. But 600mA of error on a 1A signal seems suspect. We are doing much better than that.+/-(4% + 1A) at 50/60Hz for 2-300A. At the 3.5A, again we are much tighter.

author: J-R
author_rank: Super Contributor
timestamp: June 24, 2024, 12:27:41 am
content: Quote from: Astray on June 23, 2024, 01:02:03 pmTo start, you could consider various accessory clamps from Fluke and AEMC (Chauvin Arnoux), such as the Fluke Y8100 and 80i series, and AEMC SL2xx series (and Fluke and AEMC in general).Also, there is some overlap in this area between DMMs and oscilloscopes. Converting from BNC to banana jacks (or vice versa) is trivial.However, despite having the PDI CA60 and some others, for portable DMM use I can't say it's worth it. For the money and size/weight of the current clamp accessory, you could simply buy an entire clamp DMM and carry that in addition (or instead). For the compact form factor, there is the famous Uni-T UT-210 series, the Brymen 03x series and many others. Which to choose will come down to features and range/accuracy requirements.

author: TomKatt
author_rank: Frequent Contributor
timestamp: June 24, 2024, 12:47:12 am
content: Quote from: J-R on June 24, 2024, 12:27:41 amThat’s an excellent point - while these products do exist, it’s more cost efficient to just purchase a clamp meter. Plus, they eliminate any conversion calculations by displaying the actual current.

author: Astray
author_rank: Contributor
timestamp: July 02, 2024, 12:33:47 am
content: Thank you guys for the info about the clamp!Also I made a discovery concerning the BM786 and BM789 and made another post about it that might be of interest to some.

author: sonpul
author_rank: Regular Contributor
timestamp: July 09, 2024, 01:02:03 pm
content: Greetings to all. Question.What is this pictogram(((D)))and why is it there?

author: BillyO
author_rank: Super Contributor
timestamp: July 09, 2024, 02:20:57 pm
content: It's not mentioned in the manual and I can't get it to come on, but I do see it there when I first turn it on. What did you do to get it to come on?

author: sonpul
author_rank: Regular Contributor
timestamp: July 09, 2024, 03:03:04 pm
content: SetVAC VFD ; ~Hz ; RECAn icon(((D)))will appear. You can leave Hz, leave VFD measurement, leave REC while remaining on VAC. The icon will remain displayed until you turn the selector.

author: TomKatt
author_rank: Frequent Contributor
timestamp: July 09, 2024, 03:40:10 pm
content: Data (logging) ?

author: sonpul
author_rank: Regular Contributor
timestamp: July 09, 2024, 03:56:27 pm
content: Via bluetooth? Which was planned, but never appeared. It looks more like a sound symbol, a signal symbol.

author: BillyO
author_rank: Super Contributor
timestamp: July 09, 2024, 07:24:52 pm
content: Quote from: sonpul on July 09, 2024, 03:03:04 pmThat works. Hmm, most likely something only partially implemented.

author: EEVblog
author_rank: Unknown
timestamp: July 10, 2024, 07:22:06 am
content: Quote from: sonpul on July 09, 2024, 03:56:27 pmYes, bluetooth was planned and they promised it but it never happened

author: YulyPH
author_rank: Newbie
timestamp: August 05, 2024, 06:25:10 pm
content: Had my brand new BM789 (from welectron with dakks calibration) for a week and I just want to share some info.Firmware version is 13 so I guess they are still making improvements.BM869s seems like a mistake as BM789 is better for AC voltage (more accurate voltage up to 100kHz - both meters go higher than that) and the readings are way faster (BM869s needs a few seconds to stabilize).BM869s has the edge only in AC current but BM789 is not that far off, even if the datasheet lists only 3kHz it goes almost as high as BM869s.I strongly recommend lubing the rotary switch as it's quite bad feeling out of the box. Super lube works perfectly.Now for the those that like to compare backlight duration.Every DMM that I owned switched the backlight throw a transistor so you could replace it with a resistor to limit the current and have the battery last longer with always on backlight.Why do Brymen meters have backlights as bright as a flashlight ? If I want a flashlight I don't use a DMM.The BM789 is a bit special as the backlight is connected directly to the battery so it's not going throw the rotary switch.The only way to have always on backlight is to get a voltage to the base of the transistor that is switched from the rotary switch (luckily there is a 3.5V track next to the transistor base track).The mod can be done without removing the screen (just the plastic that holds the screen and backlight board then remove the backlight board with care) and is doable on the front or the back of the meter (I recommend cutting the transistor base trace and attach it to the 3.5V rail).Anyway, around 60mA with default 150R resistors (R57, R58 and R84) and 17mA with 500R resistors (the result is more than enough backlight).Even with good environment lighting the backlight makes the screen more readable.Maybe one day Brymen will copy Uni-t(UT622 LCR meter with color screen and backlight adjustable from keys is just perfect or maybe UNI-T UT181 but I don't own one to be sure the screen is good).

author: joeqsmith
author_rank: Super Contributor
timestamp: August 05, 2024, 07:50:16 pm
content: Quote from: YulyPH on August 05, 2024, 06:25:10 pmBM869s supports logging, dual display, and while a few claim the 500k count is a gimmick, I have used it to hunt problems.I suggest buying the tools that fit your personal needs. The only mistake is not doing your homework.

author: YulyPH
author_rank: Newbie
timestamp: August 05, 2024, 10:07:26 pm
content: Quote from: joeqsmith on August 05, 2024, 07:50:16 pmYour right, and here we are talking about portable DMM's that are general purpose meters.The 500k count is considered a gimmick because it's useless without measurement precision and stability.The BM789 has the extra digit for frequency in contrast to BM869s extra digit for DC voltage.BM869s and BM789 are above budget toy meters but at the same time they are not lab grade (maybe entry level).As long as you don't need data logging the BM789 seems the better one as a general purpose meter.And this was the answer that I was searching for that no one seemed to give.Even ChatGPT says that BM869s has better accuracy with more features and the BM789 is the budget optionBoth calibrated and purchased a week apart from each other on DC they agree and for AC voltage the BM789 is way better.Had to get them both to reach this conclusion.

author: joeqsmith
author_rank: Super Contributor
timestamp: August 05, 2024, 10:16:54 pm
content: Quote from: YulyPH on August 05, 2024, 10:07:26 pmI was once told there was never a reason to measure anything beyond 60Hz. In many cases, I am looking for a relative change only. Obviously your use case is different. Not to suggest your statement is wrong but that we all have different requirements.

author: J-R
author_rank: Super Contributor
timestamp: August 06, 2024, 06:30:04 am
content: The 500,000 count mode on the BM869s can win out over the BM789, for example 7V. You lose a digit on both going up a range, but you can bring it back on the BM869s and it's going to be a usable digit.The dual display on the BM869s is hard to beat, but on the flip side the BM789 has AutoV/LoZ and NCV detection. Brymen just wants you to own both...

author: joeqsmith
author_rank: Super Contributor
timestamp: August 06, 2024, 12:16:43 pm
content: Not being an electrician, I seldom use ACA, ACV, NCV or LowZ modes. If I am looking at AC, it is normally some odd ball wave shape and I want the AC+DC with the split display. Actually, I like meters that can show even more than two parameters on one screen just to save time. Most likely I am using a scope. Having that split display for temperature has proven to be very useful.Someone else had posted about the stability of the 500k mode and I had made a short video showing a few high res meters with a somewhat constant voltage applied. It no doubt moves and has a few counts of noise but it has been good enough to spot some trends.

author: sonpul
author_rank: Regular Contributor
timestamp: August 06, 2024, 02:57:19 pm
content: YulyPHThank you.I am pleased with both the brightness and duration of the BM789 backlight.But I always wanted to have a mode so that the backlight would turn on itself immediately and turn itself off after 15 minutes.Any ideas on how to implement this?QuoteI have always said that the BM789 was created very well. What would you notice about the long backlight time, AutoHold, easy-to-read display and much morejoeqsmithBut in AC+DC mode, the main display shows the RMS calculation using the formulaAnd that's exactly what the BM789 displays.BM869s should display the same thing. Calculation of RMS using the formula.What do you want to see on the second display?What do you even see on the second display ?AC or DC or can you switch between AC and DC on the second display?

author: joeqsmith
author_rank: Super Contributor
timestamp: August 06, 2024, 03:19:51 pm
content: Quote from: sonpul on August 06, 2024, 02:57:19 pmMath isn't in question. Nor is the fact that the 789 supports AC+DC (many don't and I have to calculate by hand).QuoteBM869s will display DC and AC, or AC+DC and AC. I have a few meter that will show AC, DC and AC+DC at the same time.

author: Fungus
author_rank: Super Contributor
timestamp: August 06, 2024, 06:29:42 pm
content: Quote from: YulyPH on August 05, 2024, 06:25:10 pmI use an oscilloscope for anything "AC" that isn't mains voltage.

author: YulyPH
author_rank: Newbie
timestamp: August 07, 2024, 03:54:50 pm
content: Quote from: sonpul on August 06, 2024, 02:57:19 pmIt's hard to read the display with light glare and awkward positions without backlight so I need always on backlight.Implementing a custom pcb for the backlight is a possibility but the compact nature of the meter kinda limits what you can stick inside.Even if you do implement a custom solution there needs to be a reset for the timer (reuse a push button but lose the functionality of the meter for that button) otherwise you need to turn off/on the meter every 15 minutes.The simplest solution is to have always on display with limited current. Even with 500R resistors there isn't much of a difference in backlight.The quality of the display in BM789 is good and exactly the same as BM869s but with bigger digits. The display on BM829s looks kinda bad compared to the other two. All of them lose in top viewing angle.Auto hold is useless on fluctuating mains but I guess any fluctuating voltage source (It jumps all over the place).I do mains work on occasion so the live finder is quite useful as in my country mains wires don't have a fixed position for live/neutral in the sockets or even a specific color for the wires.Love brymen meters for having DC and AC low-z as it is very useful for discharging caps and detecting devices that have a bit of leakage (you don't need custom value resistances).Also the speed of the BM789 is unlike anything I ever had the pleasure (or not) of using.You might think BM869s is slow but it is actually second in speed.BM829s was the fastest I experienced but with the above 2 it takes thinks to another level.Quote from: Fungus on August 06, 2024, 06:29:42 pmI also use a scope for visualizing the waveform even on mains (battery powered scope) but it takes time to boot up the scope and sometimes you may need a quick value to see that it works (smps power supplies for example)Dual display becomes irrelevant with two meters sooo anyone wana trade a BM789 for my BM869s?

author: J-R
author_rank: Super Contributor
timestamp: August 08, 2024, 12:55:13 am
content: A use case can get specific enough to make one DMM an obvious choice over the other. But I'd maintain that the BM869s is better for bench use in general. Dual display and IR interface for starters. Also, the calibration procedure is known, so you can really dial in the 500,000 count modes. NCV, AutoV and Low Z are not typical on the bench, more household/industrial. Anything where the frequency performance matters should go to the scope.When away from the bench, those features really are handy, so the BM789 is easily the winner. Although, some of UEi's DMMs with Bluetooth have been handy.

author: EEVblog
author_rank: Unknown
timestamp: August 08, 2024, 02:00:01 am
content: Quote from: J-R on August 08, 2024, 12:55:13 amThe BM780 series is designed as a direct competitor to the Fluke 170 series. It's almost indentical in shape and look, and includes the more "electrical" features of NVC and LowZ.The BM869 is clearly designed as a high end lab meter.Nothing mysterious here at all, just basic market segmentation.

author: J-R
author_rank: Super Contributor
timestamp: August 08, 2024, 04:17:02 am
content: The feature set between the BM78x and Fluke 17x doesn't align well enough for me to believe that it was "designed as a direct competitor". The BM235 matches better. It seems more likely that marketing wanted a story to tell and to be able to say "Fluke" during presentations.

author: YulyPH
author_rank: Newbie
timestamp: August 08, 2024, 07:00:51 am
content: Bench use, so what exactly does this mean for you ? For me it's troubleshooting, improving stuff, basic experimentation and I guess for many more.I do watch quite a bit of youtube channels and apart from learning channels I really don't see anyone have a need for PC communication/logging.Some even use basic bottom of the barrel meters because they need a quick value then move on with there lives.I you mean lab use then that is another thing entirely and BM869s might be just a starter pack.People here are starting to agree that the scope is better for AC so what is left for dual display meters ?Diode, continuity, and DC don't need dual display, maybe capacitance for ESR but I don't see any DMM have this feature.Don't get me wrong I would like a display with as much info as possible but if it means compromising on other features than I take the single display.Considering low-z a feature for electricians is just wrong.You wouldn't want an electrician to work on your electronics.I have interacted with many electricians and none of them had a meter with low-z or even know what to do with it.Electricians like stick meters with a few leds because a number on a screen is to much and I agree with them, measuring voltage thousands of times a day becomes irrelevant if it's 220 or 230.

author: tautech
author_rank: Super Contributor
timestamp: August 08, 2024, 07:10:37 am
content: Quote from: YulyPH on August 08, 2024, 07:00:51 amFTFY.

author: J-R
author_rank: Super Contributor
timestamp: August 08, 2024, 10:17:17 am
content: You can pick apart any general statement by providing specific use cases. If you don't agree with the generalization, then that's fine. It doesn't invalidate the generalization...The workbench has your best equipment within reach, maybe more than you need. When you're away you have to make do with what's nearby. Put another way, I've got the multitool in my pocket, toolbox in the truck but tool tower in the garage/shop.Low Z has a few uses, but I say typically on the bench it's rare because you have drawers of resistors or a substitution box for creating any specific load you want. Away from the bench a common use is to see if that voltage you're seeing is "real" or just induced via nearby wiring.Sometimes your bench DMM is too far away or you want the display right next to your face when you're deep in a repair. So the BM869s seems pretty well feature packed for that. BUT, no reason a BM789 can't be fine too.And what do you say about my DMM that has a thermal camera built-in? Hit the button, now I can instantly see that loose connection or an overloaded circuit, etc. So Brymen is the loser now...

author: joeqsmith
author_rank: Super Contributor
timestamp: August 08, 2024, 11:19:43 am
content: Quote from: YulyPH on August 08, 2024, 07:00:51 amI already stated I use it for the BM869s thermocouple inputs.My scopes are limited to 8-bits. For most cases, it's not a problem for what I use it for. Here I set mine up to measure AC power by over sampling and fitting the data to remove some of the linearity errors:

author: Fungus
author_rank: Super Contributor
timestamp: August 08, 2024, 11:51:09 am
content: Quote from: YulyPH on August 08, 2024, 07:00:51 amNothing.That's why the BM857s is the best multimeter for bench use - simple, no display clutter, one function per dial position (almost).(and the Fluke 113 for "electricians" ... and you can ownbothfor less than the price of a Fluke 87V)

author: AVGresponding
author_rank: Super Contributor
timestamp: August 08, 2024, 12:33:12 pm
content: Quote from: YulyPH on August 08, 2024, 07:00:51 amClearly you don't know anycompetentelectricians. And you also misunderstand what an electrician might need a DMMfor.Two-probe/Steinel testers arealreadylow-Z, and the reason for this is simple; they eliminate ghost voltages caused by capacitive and inductive coupling, and therefore give a "true" reading of the presence of dangerous voltages. In the UK, if you want to be certified for testing fixed wiring installations to BS2391 (which you need for signing offanyelectrical alteration work that is a part of such an installation), youmustuse a two-probe tester; a DMM isnotacceptable.You'd use an installation tester in the test and verification process, which again, is already low-Z. The two-probe testers are purely for fault finding and verifying a circuit is dead, prior to locking it off, so it can be worked on.Electricians only use DMMs for things like troubleshooting industrial machinery and controls, where you need a bit more flexibilty. Basic domestic/commercial/industrial fixed wiring does not require it.NCV voltsticks are useful when you're trying to find an individual circuit in a trunking with dozens or hundreds of cables; good luck getting a DMM in there. That function on a DMM is useful only for home users/hobbyists imo.

author: EEVblog
author_rank: Unknown
timestamp: August 11, 2024, 10:28:13 pm
content: Quote from: Fungus on August 08, 2024, 11:51:09 amShots fired!I'll take the BM786 thanks.

author: J-R
author_rank: Super Contributor
timestamp: August 12, 2024, 02:55:29 am
content: That "simple" argument is objectively bogus and doesn't hold up to scrutiny. The BM857s has a significant number of shared functions and multiple settings per switch position just like the other models:BM857s has 9 function switch positions. 4 are shared functions in the strict sense. 7 have multiple settings.BM859s has 9 function switch positions. 5 are shared functions in the strict sense. 9 have multiple settings.BM867s has 9 function switch positions. 5 are shared functions in the strict sense. 7 have multiple settings.BM869s has 10 function switch positions. 7 are shared functions in the strict sense. 10 have multiple settings.BM786 has 8 function switch positions. 4 are shared functions in the strict sense. 7 have multiple settings.BM789 has 9 function switch positions. 5 are shared functions in the strict sense. 8 have multiple settings.Also, the BM857s/BM859s and BM78x have 8 buttons, while the BM867s/BM869s have 6.Ultimately, due to the mode memory that can't be disabled, all Brymen DMMs can be a pain to use in many cases because you never know what function you'll get when you flick it on, unless your life is so dull that you memorize the last setting or write it down every time you turn it off.The 121GW with the mode memory hack is a joy by comparison. The setting I'm using is remember the mode while it's on, but reset to the white-lettered functions after power-off. Predictable. Dare I say "simple".

author: Fungus
author_rank: Super Contributor
timestamp: August 12, 2024, 05:22:09 am
content: Quote from: J-R on August 12, 2024, 02:55:29 amThe only thing I really toggle on BM857s is Ohms/continuity, and it'sreallyeasy to know when it's in the wrong mode.No need to even look at the screen, just touch the probes together.Quote from: EEVblog on August 11, 2024, 10:28:13 pmThat's a good second choice but it has three functions on a single range (Ohms/continuity/Siemens)...(size is also similar)I feel this is a topic that's never been explored. Which meter needs the least button pushes and mode selections in daily use?

author: Fungus
author_rank: Super Contributor
timestamp: August 12, 2024, 05:26:34 am
content: Another topic:What's more useful?a) A BM869s,orb) A BM857s and a$30 Zeeweiioscilloscope?Edit: I should point out that the Zeeweii has an "auto" mode that scales both horizontal and vertical to match the incoming signal. It's fast at doing it, too. Just probe the DUT and there's the wave on screen complete with measurements, no need to do anything else.

author: multiJ
author_rank: Contributor
timestamp: August 12, 2024, 08:00:16 pm
content: Quote from: Fungus on August 12, 2024, 05:22:09 amFluke 117 and certain meters from Hioki (4252, 4256, 4261, 4282) come to mind, if we are not too far off topic.

author: EEVblog
author_rank: Unknown
timestamp: August 12, 2024, 11:05:30 pm
content: Quote from: multiJ on August 12, 2024, 08:00:16 pmWinner:

author: Fungus
author_rank: Super Contributor
timestamp: August 13, 2024, 12:23:38 am
content: Quote from: multiJ on August 12, 2024, 08:00:16 pmI guess I should have added "and have good accuracy specs and are not missing any major functions that an EE needs, like mA/uA".

author: porter
author_rank: Regular Contributor
timestamp: September 29, 2024, 11:54:40 pm
content: Quote from: mwb1100 on September 24, 2023, 07:36:19 pmI wanted to mention that I ordered the DM64 last year at the sale price while it was still listed on the Flir website. It didn't arrive after a few weeks, but I got a call from them telling me that they are shipping the DM66 for the same price. I'm very happy with the quality.I'm posting this ( a little bit late) because I appreciated the phone call from Flir and shipment of a newer model.

author: rce_pirate
author_rank: Newbie
timestamp: December 03, 2024, 04:18:20 am
content: new post here. the flir dm66 is the brymen 235 repackaged. better plasics though.

author: Sorama
author_rank: Frequent Contributor
timestamp: December 03, 2024, 07:21:02 am
content: I use a Brymen 785 on the bench.This model is not mentioned often on the forum.Maybe it’s not a model sold across the ocean?But I do like it a lot.

author: chebo
author_rank: Contributor
timestamp: December 03, 2024, 07:58:39 am
content: Hi owners!Who could repeat my simple experiment to check the accuracy of the Crest mode?I manually closed and opened the switch shown in the diagram, simulating a voltage drop. The average value for several measurements in the Crest mode was 7.60 V. As a result, the relative error was approximately 4%.Is this a normal error? What will happen to you?

author: joeqsmith
author_rank: Super Contributor
timestamp: December 03, 2024, 01:30:38 pm
content: Quote from: chebo on December 03, 2024, 07:58:39 amI saw your double post about the car battery. Personally, I would use a scope for that application.For the BM789, assuming we meet the 35ms minimum, in this range I would expect it to fall within +/-1V. Yours appears much tighter than that.CREST mode (Instantaneous Peak Hold)Accuracy: Specified accuracy +/- 100 digits for changes > 0.35ms in durationAvailability: Voltage and Current functionsResolution: 6000 countsFor the BM869s:Crest mode (Instantaneous Peak Hold)Resolution: 5000 countsAccuracy: Specified accuracy +/- 100 digitsfor changes > 0.8ms in durationFor the Fluke 189:Specified accuracy ±100 counts up to 5,000 count (fullrange) reading. For higher peak readings (to 20,000counts), specified accuracy ± 2% of reading.250 μs for repetitive peaks; 2.5 ms for single events. Use DC function settings below 20 Hz. 50 mV range not specified.

author: chebo
author_rank: Contributor
timestamp: December 03, 2024, 01:48:42 pm
content: Quote from: joeqsmith on December 03, 2024, 01:30:38 pmYes, it seems so. And that's what Brymen's engineer answered me too: "07.60V" reading falls in "+- 100 digits" tolerance.It was not very clear to me what these +-100 digits meant. But now everything has become clear. If you add this systematic error to the readings, the result coincides with what the oscilloscope showed.

author: coromonadalix
author_rank: Super Contributor
timestamp: December 03, 2024, 02:44:22 pm
content: brymen 785 would be like some fluke 83 85 87 series ... no dual displays, but vs the dual display ones, the price gap is not huge ... ?old Gossens have the auto mode i sometimes use, switch between ohms volts ... practical loll

author: joeqsmith
author_rank: Super Contributor
timestamp: December 03, 2024, 06:27:35 pm
content: Quote from: chebo on December 03, 2024, 01:48:42 pmI had a quick look at the manuals for some of the other higher end meters I have on-hand but don't believe any of them are spec'ed much better.

author: AVGresponding
author_rank: Super Contributor
timestamp: December 04, 2024, 06:18:19 am
content: Quote from: BillyO on August 09, 2023, 02:16:43 pmHere's your bulletproof plastic:https://www.eevblog.com/forum/testgear/brymen-bm786-case-cracking/

author: Jester
author_rank: Frequent Contributor
timestamp: July 02, 2025, 02:28:13 pm
content: I just ordered a BM789.Seems like a good fit for me.My biggest concern (long term reliability) is the more finicky traces around the selector switch and the zebra strip.I see comments about selector switch endurance testing (some other video that I have yet to find), can anyone comment on that aspect?Has anyone done endurance switch testing on this particular meter?Someone suggested superlube is a good idea, it might be welcome comments on that as well , sometimes what seems like a great idea is bad for plastics or even the contacts if there is creep in the long term.Much appreciated.

author: joeqsmith
author_rank: Super Contributor
timestamp: July 02, 2025, 04:52:27 pm
content: Quote from: Jester on July 02, 2025, 02:28:13 pmI would not suggest ever making any modifications to a handheld meter. Shown below, my switch testing and another where someone was suggesting using Vaseline in a DMM.

author: Jester
author_rank: Frequent Contributor
timestamp: July 06, 2025, 08:24:34 pm
content: Well BM789 arrived quickly from Poland (2 days).I have ac/dc calibrators to 1kv.I checked function and accuracy and all looks good.Initial impression is very good.Big thanksto Joe Smith for the evaluation videos. Invaluable for making an informed purchase decision.I tried to view/download the spreadsheet with summary of failure points, but the link is not working for me.I tried again and succeeded.