Metrix MX554 bench multimeter - a 17 year old time capsule

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Hi

I stuck a low bid on Ebay for this multimeter, chiefly because I was intrigued to take a look at it. I ended up paying £26 for it, with a fiver delivery - so tell me whether I got my money's worth at the end!

The seller described it as brand new old stock, dating from 1996 - though it's actually 2 years younger than that. It's a 50,000 count, 0.05% DC Volts accuracy meter. Metrix was originally a competitor to Chauvin Arnoux, but joined forces in 1997, just before this meter was sold.

The Ebay seller goes by 'measurements', but are actually a test equipment hire/calibration firm called Inlec, based in Stokesley, North Yorkshire. The box arrived via DHL, on a Sunday! Not bad for a fiver.

Anyway, on with the show.



An unassuming box.



A4 manual in a variety of languages, fortunately including English.



Drivers for the RS232 connection, on 3.5" floppy. Might need a FDD...



April 1998!



I wonder if I should post this off?



Leads all still coiled up.



Nice, too - sharp point plus banana plug.




Ooh - the film is still on the display.


I love peeling those off...


And here it is - front.



And back



Next post - we crack that sucker open.

(to be continued)

[icon]

Next, a quick look inside. There's a lot of shielding going on. Also a lot of empty space. I wish they'd packed it into a smaller box.



A closer look. There's interesting bits lurking under that shield, which is unfortunately soldered down.



The power supply, plus what look like isolation for the RS232 TX and RX?



A closer look at that bit - can that be optical isolation done in discrete components?



The back of the input board. Someone will be along in a minute to talk about input protection.



Just the back of the display board.



Although it's supposed to be calibrated by RS232, there still seem to be a handful of twiddly bits.




So how does it perform after 17 years in a box? Stay tuned...

(to be continued)

[macboy]

Very nice, and very familiar. It has similar functions and buttons to my B+K 5360 (handheld) which was made by Metrix and sold by them as the MX56. The software for the "ASYCII" is common to these. You can download it from B+K. Take a look at my old post here. It gives a link to "AK5350" software which can be used to calibrate many of these ASYCII meters, probably this one too. And there is a link to the serial protocol so that you can control it and capture data over the serial interface. For my handheld, I built a simple IR-to-serial adapter using a $1 USB-TTL serial dongle, and IR Led, and a phototransistor and a couple resistors. Your job is easier.

Labview Drivers: http://www.bkprecision.com/downloads/software/AK5300.zip (same as your diskette)
Calibration software: http://www.bkprecision.com/downloads/software/AK5350.zip
Serial protocol manual: http://www.snesometel.com.tn/images/PDF/NF-SX-ASYC2.pdf

Those twiddly bits are probably for AC compensation, to get as flat a response as possible at higher frequencies (compensation for parasitic capacitances that cause rolloff).

You definitely got your money's worth.

[Vgkid]

interesting little meter, gotta love the French.

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Finally, what's it like on the bench, and how does it perform?

First, it's a bit bigger in Real Life than I had guessed from the Ebay listing. Here it is with a Fluke 8050 perched atop, for scale.



It's hard to capture the contrast of the LCD - it's better than either of these two photos would suggest. The digits are 20mm high, but it's crying out for a backlight.







The selector is OK, but it's not going to keep Fluke awake at nigh worrying. Buttons would have been nicer, but I assume this is a repackaged handheld meter.




There's a comprehensive range of functions, including esoterica like positive-going and negative-going duty cycle - which agrees with my FG!



And then there's the accuracy. How's it fared after 17 years on a shelf? Well according to my Ebay voltage standard, it's within spec - 0.04%. The interesting thing is how consistent it is - almost exactly 0.04% across 4 voltages. The graph below shows all of the meters I had to hand (I was trying to establish whether the voltage standard could be believed). They all vary to some extent - except the Metrix! Not sure what I can read into that.





I've had a play with some 1% tolerance caps, compared it for resistance with other meters (I don't have any precision resistors for an absolute standard) and fed it some waveforms for frequency and AC RMS - all seems within spec. The only thing I can find that's not up to par is the continuity tester, which is hands down the worst I've ever used. Slow and scratchy.

Anyway, I hope that's of interest - and did I get 30-quids-worth?

Regards
John

[retiredcaps]

Anyway, I hope that's of interest - and did I get 30-quids-worth?

Thanks for the pictures, commentary and test results.  I think you got your money's worth! 

[EEVblog]

Never seen one of those before, that display is huge!

[tautech]

Next post - we crack that sucker open.

Noooo, you'll void the warranty. 

[xrunner]

Very cool! Thanks for the pics. Now I want one!

[Lightages]

Looks like you got a good buy to me! It is probably pretty rare too.

[icon]

Thanks for those links - very useful. I think I'll get a suitable serial cable and have a play. Looks like a 25 pin female to 9 pin female (for my old laptop I keep for occasions such as these) null modem cable would be required?

I can't find any info via google from anyone who's actually tried calibrating one - have you?

Cheers
John

Very nice, and very familiar. It has similar functions and buttons to my B+K 5360 (handheld) which was made by Metrix and sold by them as the MX56. The software for the "ASYCII" is common to these. You can download it from B+K. Take a look at my old post here. It gives a link to "AK5350" software which can be used to calibrate many of these ASYCII meters, probably this one too. And there is a link to the serial protocol so that you can control it and capture data over the serial interface. For my handheld, I built a simple IR-to-serial adapter using a $1 USB-TTL serial dongle, and IR Led, and a phototransistor and a couple resistors. Your job is easier.

Labview Drivers: http://www.bkprecision.com/downloads/software/AK5300.zip (same as your diskette)
Calibration software: http://www.bkprecision.com/downloads/software/AK5350.zip
Serial protocol manual: http://www.snesometel.com.tn/images/PDF/NF-SX-ASYC2.pdf

[macboy]

Thanks for those links - very useful. I think I'll get a suitable serial cable and have a play. Looks like a 25 pin female to 9 pin female (for my old laptop I keep for occasions such as these) null modem cable would be required?

I can't find any info via google from anyone who's actually tried calibrating one - have you?

I played with the calibration software, and it works, but I never did save the calibration data back to the meter. You can specify ahead of time which functions and ranges to adjust and what value to use (default is 49000 scaled to the range, so 4.9000 V for 5 VDC range). There is also a verification procedure which only verifies against specs without adjustment, which is actually all that routine "calibration" really entails.

I also created a little HTML application (basically a web page that Windoze runs with full application permissions) that implements a remote interface.

Let me know if the software and command set work for your meter, I am confident that they will. I am curious which instrument this reports itself as (see status word, 5.2.2.2).

edit:
Just found this multi-lingual manual online:
http://docs-europe.electrocomponents.com/webdocs/01c4/0900766b801c48fb.pdf
It has the serial protocol documented, which matches the one in the other document I linked (although this spec is a subset of the other one which covers all ASYCII meters).

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Hi

Thanks for the reply. Unfortunately, I can't get the software to install on my XP machine - I get a 'Shadow - an error has occurred in your application' message. I've started a thread in General in case someone has encountered this or knows how to get round it.

The pdf you linked to is the same as the manual that came with the meter.

Hopefully I can find a way of getting this running!

John

[macboy]

Hi

Thanks for the reply. Unfortunately, I can't get the software to install on my XP machine - I get a 'Shadow - an error has occurred in your application' message. I've started a thread in General in case someone has encountered this or knows how to get round it.

The pdf you linked to is the same as the manual that came with the meter.

Hopefully I can find a way of getting this running!

John

It is an old 16-bit application. Try installing using compatibility mode set for Win95 or Win3.1. I have it running on two or three different XP machines.

[icon]

Hi

Thanks for the reply. Unfortunately, I can't get the software to install on my XP machine - I get a 'Shadow - an error has occurred in your application' message. I've started a thread in General in case someone has encountered this or knows how to get round it.

The pdf you linked to is the same as the manual that came with the meter.

Hopefully I can find a way of getting this running!

John

It is an old 16-bit application. Try installing using compatibility mode set for Win95 or Win3.1. I have it running on two or three different XP machines.

Yes, I've tried both Win95 and Win98 compatibility modes - no joy. Something odd about my XP machine, perhaps.

J

[coromonadalix]

Reviving this thread        wow  I was desperately searching for a teardown and software ....  contacted BK support, received nah dah,   still waiting for Chauvin Arnoux (Metrix)  answers ..


Scored the MX556 clone on ebay,  an BK Precision 5490, there is BK 5460 and BK 5470 models ...

thanks for the calibration software link, and pictures, saved copies of it ...

Will check the cals very soon

[macboy]

You will want to check out this other thread
https://www.eevblog.com/forum/testgear/metrix-mx56c-bk-precision-5390-multimeter-teardown/msg1319963/#msg1319963
There I recently posted about the full version of SX-DMM, the data logging and graphing software, that I found is now freely downloadable on the Chauvin Arnoux support site.
I'm not clear, did you buy a 5390 handheld? I'd love to have one, been watching eBay literally for years and have never seen one come up.

[coromonadalix]

thks  just saw this one too

I was checking for at least 50k count bench meter at a really cheap price, since i almost ruined myself with 2 gossen m28s and their usb / rs232 acessories recently  loll

I bought this one from ebay :  https://ibb.co/d3HSaw      BK Precision 5490 model,  50000 count bench meter

I admit i was stupid not checking correctly the calibration procedures ...

I started to freak out when i contacted BK Precision for support, they told me they had anything left for it since 2002, no papers, no procedures ... while googling for "50k bench meter"  i saw the metrix equivalent pictures posted / threaded here,  sent an email to Chauvin arnoux (Metrix) since it is an Metrix MX 556,  still no response for an software or an updated one ??

Just have to find a cheap windows 95-98 portable, i have only 64 bit oses at hand   loll

Near me i have a calibration facility,  but they aren't able to calibrate it without the software ... but they can specs it for 75$ to help me know how well it will or may work ??   

I have a calibrated fluke 85 at my job to put against it ...  i have to calibrate my gossens eventually, 120$ each at transcat   outch outch

I hope the linked software AK5350.zip will work ... trying to build an win95 VM right now,  installed the sx-dmm software just to see it work, seems nice

There is an mx57 ex meter for sale right now on ebay, seems in really good shape  loll



@ Macboy   could you send me a download link / file of you html programm to play with ??  thks

[macboy]

Oh I see, it's a bench version of the 5390. Interesting.
I think the latest SX-DMM is compatible with 64 bit modern windows versions. No need to go back to win 95. Ever.
The calibration software is 16 bit Windows app. You'll need a 32 bit version of Windows (e.g. XP) to run it.
I'll see if I can dig up my html app.

[Hydrawerk]

I think that HP / Agilent / Keysight 34401A DMM was introduced back in 1996 or so.

[coromonadalix]

The main chip is an Metrix DM5, and an AD636 for rms conversions, seems to have the internals of the handheld MX 5x Metrix series or the BK Precision 5360 thru 5390 series

Added an Delta ac line filter, changed the db25 male pinout to a female one and changed the rs232 lines accordingly, the test is done simply by pushing the print button ... at 2400 bauds

Now i have an SeaLevel Sealink FTDI opto isolated usb to rs232 adapter connected to it, lucky me it has an db25 connector to it  I simply hacked the vid pid to match normal FTDI hardwares id's, Sealevel software is a pain in the ...

I have received the latest version of the calibration software, it is v2.3 Win 7 compatible, not tested on Win 10    PM me to obtain a link for it. 

It download the calibrations values into the software, if you cancel the calibration it will simply rewrite all of them into the meter cpu  ...

There's lots of space under the lcd on one side,  i will try to find an 5 vdc led backlight to give some display punch ...

The display is big and i love it, the continuity buzzer is fast and you will know if your leads have any surfaces defects (scratchy) ... love the burned fuses warning when i had not locked enough the fuses sockets.

The only drawback is a +/- 2 readings secs speed ...  It's an oldie but a goodie

[coromonadalix]

Calibration software

http://www.chauvin-arnoux.at/sites/default/files/download/sx-asyc2cv23.rar