Author Topic: If Brymen BM869s is cheaper and as good, why people would still buy Fluke?  (Read 117206 times)

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Offline Lightages

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Some factual reasons why someone may prefer a more expensive Fluke 87V:
Low burden voltage
Hi Z mode
High diode test voltage
Frequency trigger on +/- slope
Smoothing option on display
Backlight on/off switch with intensity control
Bargraph zoom mode
Peak Hold 250uS
Standard hold and auto Hold
Battery life 400 hours
High voltage warning on display
IP30 rating with 1 meter drop test
Long warranty period
Easy after sales service

All valid points in favor of the 87V, except the burden voltage of most of the Brymens is very good too. Another; "Easy after sales service" depends on where you are. The same could be said for Brymen, depending on where you are.

It would really be nice if people would present a balanced view instead of just promoting what they want to promote. There are reasons to consider many brands such as Fluke, Keysight, Gossen, Brymen, Amprobe, etc. All have their benefits and drawbacks. Some brands are just not worth considering at all for most people either for high price or for poor quality.
 

Offline Lightages

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A "better resale value" is pretty vague. If I buy something for $100 and sell it for $50, is that a worse resale value or better than buying something for $200 and selling it for $100? What do you mean? Please be more specific. Are you talking in percent difference adjusted for inflation or just the simple difference between buy and sell price?
 

Offline Wytnucls

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Burden voltage 1.8mV/mA on 60mA range, Brymen 3.3mV/mA on 50mA range, not bad but still nearly twice as much.
If you live in Taiwan, I suppose after sales service might be good.
 

Offline joeqsmith

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What if my 869S fails out of warranty ?

Simple, i'll buy another one (or something else, if available), still saving money against a single Fluke 87V and taking advantage with :

- double thermocouple reading
- double display
- additional resolution digit
- pc interface

all things that i care for .


That double thermocouple is very nice!   

I like that the Brymen stores the settings.  I really like the ability to measure 1G resistors.  I wish I could measure a couple of UX FOBs in series but I have a power supply and know how to use it.    I don't worry about the Brymen getting damaged.  It's proven it can take a fair amount of punishment.   Mine survived with a 6KV transient.  The 87Vs I have looked at, not so much.  The last one failed with a 1.5KV transient.   Imagine having to remove the PCB to change a fuse.   The frequency counter for the 87V I looked at last was only good for about 1.5MHz and my Brymen is not much better at 10 or so but really, I have counters and never use the feature anyway.  Sort of like the crest mode.  I have a scope and use it.   

My Brymen gets used more than any meter I have now and still has the factory supplied battery.  When will it die??!!

Down side after having it for several months now.   Kick stand is too narrow for height of meter and I don't like how it is latched.   The LCD cover could have been made of a more scratch resistant material.   The continuity test on the Brymen is not fast enough to play Van Halen's Eruption.   
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline Lightages

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Burden voltage 1.8mV/mA on 60mA range, Brymen 3.3mV/mA on 50mA range, not bad but still nearly twice as much.
If you live in Taiwan, I suppose after sales service might be good.

Are you trying to get me to list all the benefits of the BM869S again? Nah, I don't want to repeat myself again. Like I have said, every time, over and over and over, each can choose his own preferences. I just wish people to not be sheeple and do what someone else tells them is best without looking at the facts from a non fan boy point of view. I think I have even recommended a few Uni-Ts many times, Amprobes, Flukes, and maybe some others.....

The fact is, each manufacturer and model from those manufacturers have their benefits and drawbacks. Choose what meets your needs, and don't pick one brand because the hordes say so. Education and honesty get you the best decision, not religion for a brand.
 

Offline joeqsmith

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Burden voltage 1.8mV/mA on 60mA range, Brymen 3.3mV/mA on 50mA range, not bad but still nearly twice as much.
If you live in Taiwan, I suppose after sales service might be good.

Are you trying to get me to list all the benefits of the BM869S again? Nah, I don't want to repeat myself again. Like I have said, every time, over and over and over, each can choose his own preferences. I just wish people to not be sheeple and do what someone else tells them is best without looking at the facts from a non fan boy point of view. I think I have even recommended a few Uni-Ts many times, Amprobes, Flukes, and maybe some others.....

The fact is, each manufacturer and model from those manufacturers have their benefits and drawbacks. Choose what meets your needs, and don't pick one brand because the hordes say so. Education and honesty get you the best decision, not religion for a brand.

Hang on there!!  You sir made me a Brymen Fan Boy!!!  I never heard of them until you talked about shipping the one.   So that's on you!  :-DD

And as much as I am not a Fluke follower and still would not consider one of their high end meters, I have to say that looking at how robust their low cost meters are,  the worst of the them is still above all of the meters I have looked at.  If they ever make a high end meter I want, I will buy it.   
How electrically robust is your meter?? https://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline Wytnucls

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The point of the thread is not about which meter is better, but why someone could choose to buy the more expensive Fluke over the Brymen, for a specific item he needs that the Brymen is lacking.
We know that the Brymen is equal or superior in most other areas.
 

Online wraper

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Better resale value  :-+
Or just Buy one Brymen, After 10 years buy another without selling the first one. Same money spent, 2 meters instead of one. One of them is new. With fluke, you would be able to change one used fluke for another used fluke.
« Last Edit: March 03, 2016, 01:27:11 am by wraper »
 

Offline mos6502

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Better resale value  :-+
Or just Buy one Brymen, After 10 years buy another without selling the first one. Same money spent, 2 meters instead of one. One of them is new. With fluke, you would be able to change one used fluke for another used fluke.

The problem with that logic is, I can get a used Fluke 87V for less than a new BM869s:

http://www.ebay.de/itm/Fluke-87-V-True-RMS-Digital-Multimeter-/141917745559

(Just an example. I have nothing to do with that auction. But used Fluke 87Vs go for around 250€ on eBay.de. Many of them in like new condition).
for(;;);
 

Offline Wytnucls

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I don't own a Fluke 87V, but according to the instruction manual, there is no need to remove the PCB to replace the fuses. The front cover comes off, after 3 screws are removed.

1. Turn the rotary switch to OFF and remove the test
leads from the terminals.
2. Remove the battery door by using a standard-blade
screwdriver to turn the battery door screws one quarter
turn counterclockwise.
3. Remove the three Phillips-head screws from the
case bottom and turn the case over.
4. Gently push up the input terminal-end of the top case
from inside of the battery compartment to separate
the two halves of the case.
5. Remove the fuse by gently prying one end loose,
then sliding the fuse out of its bracket.
 

Offline jwm_

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Heh. this thread has convinced me to get a used 87V for $200. Of course, i already have many meters, bryman, fluke and otherwise. I think this can replace my u1272a (I also have a u1273a that is my goto meter, but keep the 72a for the LCD when i need to work outdoors but feels silly having two almost identical meters)

Although in general i work on a bench, while installing solar panels I did drop my fluke 117 off a two story building onto concrete with no ill effects other than a very scuffed jacket, so, I am fairly convinced of their reliability (though pretty sure there was a strong luck factor there). Will bring my brymen up next time i am on a roof in case I accidentally get to make the same impromptu test and report back.

Online wraper

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Better resale value  :-+
Or just Buy one Brymen, After 10 years buy another without selling the first one. Same money spent, 2 meters instead of one. One of them is new. With fluke, you would be able to change one used fluke for another used fluke.

The problem with that logic is, I can get a used Fluke 87V for less than a new BM869s:

http://www.ebay.de/itm/Fluke-87-V-True-RMS-Digital-Multimeter-/141917745559

(Just an example. I have nothing to do with that auction. But used Fluke 87Vs go for around 250€ on eBay.de. Many of them in like new condition).
Without knowing if it is not fucked up, if calibration is right. Without any warranty as lifetime warranty is only for original buyer who bought from authorized distributor. And the most of all, you never had a new meter, always using what other people don't need anymore (generally I have nothing against it).
For 240-250 EUR (inc VAT) you can buy a brand new BM869S
 

Offline splin

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And matching resistors? Seriously? Let's say the contact resistance of the probes will introduce an error of 100 milliohms (which would be a very good value). That's 0.1% on a 10k resistor and 1% on a 1k resistor. A handheld multimeter is the wrong tool for the job. You need a bench multimeter or an LCR meter that allows for 4-wire measurements. Unless you don't care about a 0.1-1% error ... but then you might as well buy 0.1% or 1% resistors.

100 milliohms measurement error on a 10k resistor is 0.001%. Seriously.

Now what was your point?
 

Offline Robomeds

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The used vs new is probably a legit decision for us home users but not for many companies.  If I were the purchasing guy for a company there is no way I would be buying used with unknown history.  If we were working with high power I would worry about safety.  If we needed high accuracy I would worry about damage that might result in failing calibration.  If I didn't need to worry about either one I probably won't be considering buying a Fluke 87V.  In that case a Fluke 115 or Brymen 257 based Greenlee would make more sense.  As a hobbyist I'm very concerned about cost but for a company that extra $200 may not mean much depending on the circumstances.  In others it might but buying used is probably something a company will try to avoid. 
 

Offline mos6502

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100 milliohms measurement error on a 10k resistor is 0.001%. Seriously.

You are correct. My bad. So that would be a viable application for the 500.000 count mode. You could also use it find out the amount the meter drifts over time. I.e., measure a (low drift) resistor, note the value, measure again after 1 hour, 1 day, 1 week, 1 month ... to tell you how repeatable the measurements are.
for(;;);
 

Offline 3141592

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I don't know why no one ever mentions other uses for the resolution other than watching a battery discharge, but the 500k counts mode sees regular use on my BM857. For once, it provides µV resolution on the mV range, and it worked great for monitoring the output of Wheatstone bridges for example. I also use the meter fairly often to match resistors, although it's only 50k counts in that mode. I have never had a need for the crest/peak function though. So I guess we can agree that different people want different features from their DMM.

The reason why no one ever mentions other uses is because resolution is not accuracy. The accuracy is specced at 0.02% +-2 digits, the digits referring to the 50.000 count reading.  Example: you're measuring a 5.00000V precision reference. The 869s could be displaying anywhere from 4.99880 to 5.00120. Those extra digits are nothing more than a gimmick.

So? That's why I listed using it for relative measurements, such as matching components or watching change in the output of a Wheatstone bridge, which is a great real world use, because it both needs measurement down to the µV-s, and high resolution, because the few µVs change may ride on an offset that's two orders of magnitude larger. I don't care if it's 1% out compared to a NIST standard, I just want my ADC to be linear. Resolution not being accuracy is exactly why they make you press a button to go between 50k and 500k modes and it's not 500k by default.

And matching resistors? Seriously? Let's say the contact resistance of the probes will introduce an error of 100 milliohms (which would be a very good value). That's 0.1% on a 10k resistor and 1% on a 1k resistor. A handheld multimeter is the wrong tool for the job. You need a bench multimeter or an LCR meter that allows for 4-wire measurements. Unless you don't care about a 0.1-1% error ... but then you might as well buy 0.1% or 1% resistors.
100 milliohm (0.1 Ohm) is about what shorting my probes together gives, most of that is the cabling, I'd guess the contact resistance part of that is way under 10 milliohm if I make good contact. I'm not talking about those cheap 5$ ebay probes though. I would say that that's more than fine for 100 ohms or bigger resistors as 10 milliohm results in a 0.01% error on 100 ohms, 0.001% on 1k, 0.0001% on 10k etc...

Exactly. The whole 500k count mode is a gimmick. They Brymen engineers knew it wouldn't matter if they implemented it properly or not - they could've simply left it off.

Can we agree now, that different people want different features from their DMM, and there are valid uses for the Brymen's high resolution?
« Last Edit: March 03, 2016, 07:49:24 am by 3141592 »
 

Offline Wytnucls

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If one doesn't have an LCR meter, up to a point, matching resistors is possible with the 87 too, as the HiRes mode (20,000 count) is available in the Ohms mode.
'Watching the output of a Wheatstone bridge'. What on earth do you do that for? Can you expand?
 

Offline 3141592

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If one doesn't have an LCR meter, up to a point, matching resistors is possible with the 87 too, as the HiRes mode (20,000 count) is available in the Ohms mode.
Sure, I just mentioned it as an example for an application that actually benefits from higher resolution.

'Watching the output of a Wheatstone bridge'. What on earth do you do that for? Can you expand?
Strain gauge measurements. There are of course application specific instruments for this, but having a meter that's able to do quick checks on the setup was great.

I'm not saying either of these are everyday tasks, just that there are actual real world uses for a higher than normal resolution DMM.
 

Offline Tim F

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If all you want to do is match resistors then you don't need a fancy 20000 count meter anyway. Just build Wien bridge and measure the mV imbalance by swapping in different resistors for one leg of the bridge. As long as your resistor values/ratings allow you to put a decent voltage across the bridge (say 20-30V) without significantly heating up the resistors then 0.01mV res gives you pretty good resistance resolution (<0.00005%). Comparatively, using a Fluke 87V in high res resistance mode only gives 0.005% resolution. The probing setup in the former will probably be the limitation.
« Last Edit: March 03, 2016, 11:28:58 am by Tim F »
 

Offline 3141592

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If all you want to do is match resistors then you don't need a fancy 20000 count meter anyway. Just build Wien bridge and measure the mV imbalance by swapping in different resistors for one leg of the bridge. As long as your resistor values/ratings allow you to put a decent voltage across the bridge (say 20-30V) without significantly heating up the resistors then 0.01mV res gives you pretty good resistance resolution (<0.00005%). Comparatively, using a Fluke 87V in high res resistance mode only gives 0.005% resolution.

Why a Wien bridge? A bridge configuration provides a lot more accuracy sure, but if you work with ordinary resistors that additional matching accuracy will be swamped by tempco differences on just a few Celsius away from the matching temperature. So above a few tens of ppm matching needs it's just an unnecessary complication IMO, below that the tempco mismatches make it meaningless for most applications, because you should use specialty matched pairs anyway.
« Last Edit: March 03, 2016, 11:40:42 am by 3141592 »
 

Offline Wytnucls

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Read this paper about Wheatstone bridge and DMMs.
It implies that a multimeter high resolution is not essential, to determine the resistance of an unknown element, like a pressure sensor.
 

Offline 3141592

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Read this paper about Wheatstone bridge and DMMs.
It implies that a multimeter high resolution is not essential, to determine the resistance of an unknown element, like a pressure sensor.

Was this meant for me? If so, then it differs substantially from my use case, in that they use a decade box to dial in a state of balance and check for this state by looking for a 0V reading on the DMM between the two halfpoints of the bridge. With the balance obtained they read the value of the unknown resistance from the decade used to obtain balance. So they substitute a high resolution decade box instead of a high resolution DMM. The lower resolution DMM is sufficient, only because the error contributed by the decade is bigger. I just skimped it through, so if I missed the point I'm sorry.

Quote
due to the fact that the relative errors in the measurement of Rx are determined, in principal, by the relative errors of the resistances R2, R3 and R4 (see the relationship (7)), it follows, that to measure with high accuracy the resistance Rx, it is sufficient to use the Beha93447 as detector

Note also that they provide a 0.1 ohm resolution. With strain gauges you have to measure a couple of milliohms of change on a base resistance of 350 to 1kohms, that gives you a couple of µVs voltage difference between two states with a 5-10V excitation voltage. Dialing in a resistance to obtain balance is out of the question IMO, so you have to take that minuscule voltage difference and read out the change in resistance.
 

Offline Wytnucls

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I don't quite understand what you are trying to achieve.
Is this application a home set-up or an industrial one?
Don't you think that you are introducing a lot of noise in the system connecting your uncompensated DMM to such a delicate detector?
Is this a documented and approved procedure to log sensor changes?

Regardless, it seems to be such an extreme application, that it is unlikely to influence the average user.
« Last Edit: March 03, 2016, 02:14:33 pm by Wytnucls »
 

Offline 3141592

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I don't quite understand what you are trying to achieve.
Is this application a home set-up or an industrial one?
Don't you think that you are introducing a lot of noise in the system connecting your uncompensated DMM to such a delicate detector?
Is this a documented and approved procedure to log sensor changes?

Regardless, it seems to be such an extreme application, that it is unlikely to influence the average user.

Home set-up for experimenting. The DMM of course isn't used to take proper readouts, it was only used to do quick checks and I also acknowledged this isn't an everyday task, I just mentioned this as an example of where the high resolution was useful for me.
I don't quite understand what you mean by approved procedure, if you mean using the voltage difference between the half points to measure resistance change, then that's a standard way of dealing with strain gauges as far as I know. See page 106 'Unbalanced bridge...' and Figure 17 on page 107 in this document for example:
http://www.omega.com/techref/pdf/StrainGage_Measurement.pdf
 

Online rsjsouza

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I have used the 500k count mode in my BM857 to get current consumption trends in ultralow currents (nA) via Dave's µCurrent.

It is not a gimmick but yet another feature that, under certain scenarios and knowing its intrinsic limitations, can be useful.

OTOH I don't give a flurry animal's rear end about backlight or peak hold on my day-to-day work - yet another feature that, under certain scenarios and knowing its intrinsic limitations, can be useful.
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Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 


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