Author Topic: EEVblog #432 - Brymen Multimeters  (Read 58079 times)

0 Members and 1 Guest are viewing this topic.

Offline Spawn

  • Frequent Contributor
  • **
  • Posts: 528
  • Country: nl
  • ³²µ º'ºººº³²
Re: EEVblog #432 - Brymen Multimeters
« Reply #25 on: March 01, 2013, 12:34:00 am »
Dave, you say in the video the BM857A is rebadged as Extech MM570A but it is actually rebadged as Extech MM560A. The Brymen BM859CFa is one with 2 temperature readings like BM869 and is rebadged as MM570A  :)

Did anyone understood anything from what I wrote? Because, I am getting dizzy with all these numbers...  :o
« Last Edit: March 01, 2013, 12:41:33 am by Spawn »
 

Offline EEVblog

  • Administrator
  • *****
  • Posts: 37661
  • Country: au
    • EEVblog
Re: EEVblog #432 - Brymen Multimeters
« Reply #26 on: March 01, 2013, 01:02:36 am »
Dave, you say in the video the BM857A is rebadged as Extech MM570A but it is actually rebadged as Extech MM560A. The Brymen BM859CFa is one with 2 temperature readings like BM869 and is rebadged as MM570A  :)

Yes, I stand corrected. The BM857A is sold as an Extech MM560A

Dave.
 

Offline rsjsouza

  • Super Contributor
  • ***
  • Posts: 5980
  • Country: us
  • Eternally curious
    • Vbe - vídeo blog eletrônico
Re: EEVblog #432 - Brymen Multimeters
« Reply #27 on: March 01, 2013, 01:02:50 am »
Nope, it does not  ;)
Spawn, I guess Extech goofed up... The Brymen has one millimeter clearance (I hope the picture is clear).

Obviously this clearance may mean nothing depending on the height of the fall (and the compression of the rubber jacket).
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

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

Offline Spawn

  • Frequent Contributor
  • **
  • Posts: 528
  • Country: nl
  • ³²µ º'ºººº³²
Re: EEVblog #432 - Brymen Multimeters
« Reply #28 on: March 01, 2013, 01:25:06 am »
Spawn, I guess Extech goofed up... The Brymen has one millimeter clearance (I hope the picture is clear).

Picture is clear  :-+ and Extech is indeed ...  :--
(I hope my picture is clear too, took it with a cell phone)

 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 7547
  • Country: 00
  • +++ ATH1
Re: EEVblog #432 - Brymen Multimeters
« Reply #29 on: March 01, 2013, 01:34:23 am »
Extech is indeed ...  :--
Well, if you're really desperate, this surely will fix that problem  ;D, c'mon, 1 mm isn't that much !   .... j/k :-DD


Offline nanofrog

  • Super Contributor
  • ***
  • Posts: 5446
  • Country: us
Re: EEVblog #432 - Brymen Multimeters
« Reply #30 on: March 01, 2013, 01:35:10 am »
** I just saw that last post about the IR serial adapter.  I don't think that adapter is compatible with the 857.  That one has a long tab that fits in a slot in the BM25X meters.  The adapter for the 857 is shorter and has two wings that rotate into the housing on the meter.  I bet it would work, but it would take a lot of duct tape.
Can't tell from the pic if the cable has groves on the outside edges (thin ends) or not to fit the "wings" on the back of the BM857 (I have one).  Figured from a systems POV, they'd try to use a single interface cable for all of their models, but can't tell for sure.  :-//

A few things missing on the mini-review; the 85x has two "OFF" positions: one on each side of the rotary switch, which is somewhat convenient.
But if you're not accustomed to 2 OFF positions like me, it won't matter. I always end up turning it counter-clockwise to turn it OFF.  :palm:
 

Offline Spawn

  • Frequent Contributor
  • **
  • Posts: 528
  • Country: nl
  • ³²µ º'ºººº³²
Re: EEVblog #432 - Brymen Multimeters
« Reply #31 on: March 01, 2013, 01:42:57 am »
Well, if you're really desperate, this surely will fix that problem  ;D, c'mon, 1 mm isn't that much !   .... j/k :-DD

picture of a BIG file

LOL, I am not that desprate  ;D

But if you're not accustomed to 2 OFF positions like me, it won't matter. I always end up turning it counter-clockwise to turn it OFF.  :palm:

Same here nanofrog, I never end up at the clockwise position when i turn it off.
 

Offline Postal666

  • Regular Contributor
  • *
  • Posts: 51
  • Country: us
Re: EEVblog #432 - Brymen Multimeters
« Reply #32 on: March 01, 2013, 02:10:08 am »
A DMM fuse change is a once in a lifetime event--

Yeah, I get that.  My guess would be that the 9V "battery at the end of the meter" design limits the options for rear panel access.   :-//

Hell, what do I know? My only DMM is a Radio Shack 22-168a that I bought in HS in the mid 90's.   :palm:
 

Offline zaoka

  • Frequent Contributor
  • **
  • Posts: 376
  • Country: us
Re: EEVblog #432 - Brymen Multimeters
« Reply #33 on: March 01, 2013, 02:24:28 am »
Dave, you have REC and CREST modes for MinMax. Rec is regular MinMax while Crest they use for Peak detection (faster update speed, its like Peak on Fluke 87V).

Limitation for Brymen BM257 are:

Capacity only up to 3000uF
Diode range only up to 1.000V
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
Re: EEVblog #432 - Brymen Multimeters
« Reply #34 on: March 01, 2013, 08:09:18 am »
While scanning posts, I remembered that Kiriakos had mentioned that the Sanwa PC7000 used the same PC connector as the Brymen. Perhaps Sanwa is another Brymen re-badge/re-case.

As far as dropping a multmeter face down, everyone seems to forget that the leads will most likely be attached an they will hit before the dial does.
 

Offline Amarbir[Lynx-India]

  • Frequent Contributor
  • **
  • Posts: 431
  • Country: in
  • Indian Dealer
    • Lynx-India - Visit Us For Not So Boring Electronic Instruments
Re: EEVblog #432 - Brymen Multimeters
« Reply #35 on: March 01, 2013, 09:16:34 am »
@ All Indians ,
      I Have figured out how to sell these in india .Lets see what all models we have here would take a weeks time frame to get more info  .
Regards

Amarbir Singh Dhillon [ Lynx-India ] , Chandigarh [ India ] - > www.lynxdealerstore.com , www.lynx-india.com
Indian Distributor For  [ Autoelectric , Sofitech , IDEOfy ,Peak Electronic Design [UK ] , Anatek And Creatronica ]
My Electronics Blog - > www.lynxchandigarh.com
 

Offline Tepe

  • Frequent Contributor
  • **
  • Posts: 572
  • Country: dk
Re: EEVblog #432 - Brymen Multimeters
« Reply #36 on: March 01, 2013, 09:55:25 am »
Elma BM869

Looks like they want 50% more for the Elma name.....
But you get a nice green rubber jacket instead of the red one...  ;D

DKK 2075 + 25% Danish VAT = DKK 2593.75 (~€350) plus shipping from elma.dk.
I paid €224.69 plus shipping from TME for my Brymen BM869 a year ago, so yeah, that green jacket is expensive.
 

Offline T4P

  • Super Contributor
  • ***
  • Posts: 3697
  • Country: sg
    • T4P
Re: EEVblog #432 - Brymen Multimeters
« Reply #37 on: March 01, 2013, 01:40:42 pm »
While scanning posts, I remembered that Kiriakos had mentioned that the Sanwa PC7000 used the same PC connector as the Brymen. Perhaps Sanwa is another Brymen re-badge/re-case.

As far as dropping a multmeter face down, everyone seems to forget that the leads will most likely be attached an they will hit before the dial does.
I wouldn't think so, the sanwa PC7000 is orange backlight and it's rather old now and has a slightly different layout.
Copy maybe? I know mostly Sanwa makes their own stuff

Elma BM869
Urgh, the neon green jacket is awful. It makes the BM86* look very ricer-ish
 

Offline NiHaoMike

  • Super Contributor
  • ***
  • Posts: 8973
  • Country: us
  • "Don't turn it on - Take it apart!"
    • Facebook Page
Re: EEVblog #432 - Brymen Multimeters
« Reply #38 on: March 01, 2013, 04:52:19 pm »
Why can't more meters have built in charging using the current jack like the Agilent ones?
Cryptocurrency has taught me to love math and at the same time be baffled by it.

Cryptocurrency lesson 0: Altcoins and Bitcoin are not the same thing.
 

Offline Tepe

  • Frequent Contributor
  • **
  • Posts: 572
  • Country: dk
Re: EEVblog #432 - Brymen Multimeters
« Reply #39 on: March 01, 2013, 07:42:48 pm »
Urgh, the neon green jacket is awful.
It is, eh, different.

(I am not sure it is neon green. It could just be the lighting.)
 

Offline Clayton

  • Contributor
  • Posts: 13
  • Country: tt
Re: EEVblog #432 - Brymen Multimeters
« Reply #40 on: March 02, 2013, 12:56:08 am »
I've got the same meter as the MB857A except its branded as the AMPROBE AM-270.
Backlight is crappy as shown but cost me US$80.00.
 

Offline Lightages

  • Supporter
  • ****
  • Posts: 4313
  • Country: ca
  • Canadian po
Re: EEVblog #432 - Brymen Multimeters
« Reply #41 on: March 02, 2013, 01:30:12 am »
Actually the AM-270 is a re-cased and re-branded BM815.
 

Offline John_Edward

  • Contributor
  • Posts: 22
  • Country: 00
Re: EEVblog #432 - Brymen Multimeters
« Reply #42 on: March 03, 2013, 01:01:21 pm »
Hey, how does the 500000 count work with the accuracy and voltage ranges ?
The specs say "DC voltage measuring range - 0,01m...500m/5/50/500/1000V" and "DC voltage measuring accuracy - ±(0,02% + 2 digits)"
For example, if I measure a LiPo cell that is exactly 4.2 volts, what does the meter say ?
This is how I see it, but I'm not that sure myself:

Voltage is under 5V, so I get "4.<decimals>".
Accuracy is "±0.02%", so error there is 0.00084V.
The +2 counts means the last digit can be smaller or bigger by 2.
500000 count means the first number can be between 0 and 5 (maybe 0-4?), with total of 6 numbers on the screen.

So TL;DR:
On the BM869, would a spot on 4.2V measure as something between 4.20086 and 4,19914V ?
 

alm

  • Guest
Re: EEVblog #432 - Brymen Multimeters
« Reply #43 on: March 03, 2013, 01:33:05 pm »
I can't find it in the datasheet, but I would expect the accuracy specs to be for 50k counts mode, so the offset uncertainty would be +/- 20d in 500k counts mode. This is typical for handhelds (the Fluke 87V does the same), and +2d sounds very optimistic for a 500k count meter.
 

Offline Wytnucls

  • Super Contributor
  • ***
  • Posts: 3045
  • Country: be
Re: EEVblog #432 - Brymen Multimeters
« Reply #44 on: March 03, 2013, 01:41:59 pm »
Alm got it right. Accuracy is no better in 500,000 count mode. The only benefit is an increase in resolution.
 

Offline John_Edward

  • Contributor
  • Posts: 22
  • Country: 00
Re: EEVblog #432 - Brymen Multimeters
« Reply #45 on: March 03, 2013, 04:38:44 pm »
Hmmh...
Is the accuracy and count difference constant, or do they change ?
So if I have two 4.2V cells, can the other say 4.20104 (+0.02% +20d), and then right after the other says 4,19896V (-0.02% -20d).
Or is it so that with 4.2V, it always shows +0.015% and -9d, at least until the calibration drifts over time ?
 

alm

  • Guest
Re: EEVblog #432 - Brymen Multimeters
« Reply #46 on: March 03, 2013, 04:52:56 pm »
You can usually expect short term stability to be much better than long term stability. So two cells measured as 4.20104 V within five minutes from each other are likely much closer than +/- 0.02% +/- 20d. You can usually also expect a cell that measures 4.20114 V to have a higher voltage than one measured 4.20104 V (ADCs in DMMs are often monotonic).

I wouldn't extend this to assume that the deviation will be constant across its entire ADC range, this will also depend on properties like linearity, which are not necessarily guaranteed.
 

Offline robrenz

  • Super Contributor
  • ***
  • Posts: 3035
  • Country: us
  • Real Machinist, Wannabe EE
Re: EEVblog #432 - Brymen Multimeters
« Reply #47 on: March 03, 2013, 04:57:48 pm »
Hmmh...
Is the accuracy and count difference constant, or do they change ?
So if I have two 4.2V cells, can the other say 4.20104 (+0.02% +20d), and then right after the other says 4,19896V (-0.02% -20d).
Or is it so that with 4.2V, it always shows +0.015% and -9d, at least until the calibration drifts over time ?

That would be answered by the stability and repeatbility of the reading. How many digits of bobble is there and what is the scatter of multiple tests of the same voltage over a short time span.  At high resolutions if you dont have some form of averaging there can be a lot of bobble of the least significant digits.  IMO unless a meter is real junk the error amount and direction will be consistent other than long term drift.

Edit: Sorry Alm, you type faster than me. ;D
« Last Edit: March 03, 2013, 05:01:15 pm by robrenz »
 

Offline IanBTopic starter

  • Super Contributor
  • ***
  • Posts: 11790
  • Country: us
Re: EEVblog #432 - Brymen Multimeters
« Reply #48 on: March 03, 2013, 05:58:00 pm »
Hmmh...
Is the accuracy and count difference constant, or do they change ?
So if I have two 4.2V cells, can the other say 4.20104 (+0.02% +20d), and then right after the other says 4,19896V (-0.02% -20d).
Or is it so that with 4.2V, it always shows +0.015% and -9d, at least until the calibration drifts over time ?

In my experience, most meters read exactly the same from one minute to the next, and from one day to the next. Readings can drift over weeks and months, and will vary with temperature. Once you get down to the sub-mV digits they will also jump around due to ambient electric fields, thermal effects, and the test leads acting like antennas.

For example, here is a picture I took about one year ago:



Here is the same meter reading the same voltage source today:



There has been some change as you can see. I didn't control the temperature, so some difference might be due to the room temperature being different. The rest would be accounted for by drift in the meter or drift in the voltage reference.
 

Offline BravoV

  • Super Contributor
  • ***
  • Posts: 7547
  • Country: 00
  • +++ ATH1
Re: EEVblog #432 - Brymen Multimeters
« Reply #49 on: March 03, 2013, 06:04:02 pm »
When it comes to reading digital measurement results, my way.. (probably a lot of others as well) .. always ignore the least significant digit, then your life will be happier and your nerves will be more relax.   ;D

Also try to train and develop the mental for ignoring the last digit, that will help too.  :-DD


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf