Pages: [1]   Go Down
Author Topic: looking for a multimeter with RS232 interface  (Read 1130 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Edison Member
*
Karma: 11
Posts: 1489
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

yeppa, i am looking for a good multimeter equipped with a RS232 interface with a well documented protocol

True RMS, AC/DC voltage and current needed
nothing special else required, but it should be used remotely from the RS232

any item suggested ?
thanks =)
« Last Edit: April 07, 2013, 03:29:20 pm by lock » Logged

Global Moderator
Boston area, metrowest
Online Online
Brattain Member
*****
Karma: 444
Posts: 23863
Author of "Arduino for Teens". Available for Design & Build services. Now with Unlimited Eagle board sizes!
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

 Various models are easily found in Google:
http://www.rakuten.com/prod/tp4000zc-pc-based-rs232-auto-ranging-digital-multimeter/228104888.html?listingId=198955210
Logged

Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

Offline Offline
Edison Member
*
Karma: 11
Posts: 1489
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Various models are easily found in Google

yes, searching "multimeter with RS232" is producing results from our friend "google", but ... how many of these results are providing "programming manual" or other details about the protocol used by the RS232 interface ?

they are used only to provide you a Windows software which has this knowledge while i need to write my own data logger system (on FreeBSD), so i need details about the protocol, or should i reverse it ?
Logged

Global Moderator
Boston area, metrowest
Online Online
Brattain Member
*****
Karma: 444
Posts: 23863
Author of "Arduino for Teens". Available for Design & Build services. Now with Unlimited Eagle board sizes!
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

You will have to research them to find out, look at manufacturer's website, etc.
Logged

Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

Left Coast, CA (USA)
Offline Offline
Brattain Member
*****
Karma: 332
Posts: 16568
Measurement changes behavior
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Jameco carries one:

http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_117373_-1

And E-bay of course:

http://www.ebay.com/itm/TP4000ZC-PC-RS232-Auto-Range-AC-DC-Voltage-Amp-Res-Cap-Freq-Digital-Multimeter-/160774578693?pt=LH_DefaultDomain_0&hash=item256ee96205

http://www.ebay.com/itm/DMM-Computer-Interface-RS232-Digital-Multimeter-MAS345-/200578990892?pt=LH_DefaultDomain_0&hash=item2eb370832c

http://www.ebay.com/itm/DIGITAL-MULTIMETER-WITH-RS-232-INTERFACE-/290882745208?pt=LH_DefaultDomain_0&hash=item43b9f67378

etc, etc.

Note that on these you will have to use a RS232 to TTL serial converter chip or module before wiring them up to an arduino. None appear to have true RMS capabilities, so you will have to search some more it that is a show stopper.

I have an older Fluke model 45 true RMS bench meter that has RS232 output but have never wired it up to any of my arduino projects, just to the PC once or twice to see that it worked.

Lefty
« Last Edit: April 07, 2013, 05:49:48 pm by retrolefty » Logged

Offline Offline
Edison Member
*
Karma: 11
Posts: 1489
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

thanks you guys, what do you think about "Lafayette DMB-1" ? I don't know Lafayette at all: is it a good product ?

the DMB-1 has the RS232 interface
Logged

Offline Offline
Edison Member
*
Karma: 11
Posts: 1489
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Fluke model 45

this is a very well documented multimeter, the RS232 protocol is pretty documented and explained, unfortunately this multimeter is very expensive and difficult to be found
Logged

Offline Offline
Edison Member
*
Karma: 11
Posts: 1489
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

see this Mastech M9803R

manual
http://web.cecs.pdx.edu/~jmorris/ECE241/ECE241%20Winter%202008/ECE241L%20Labs/Instrum%20Multimeter%20-%20Mastech%20M9803R%20Guide.pdf

shot from his box, with schematic
http://www.rapidonline.com/pdf/85-2295.pdf


you can buy from amzon
http://www.amazon.com/gp/product/B0007ZKESG/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=AMH4W1K8OCGMX#productDetails

review
Quote
(1) Lightweight
(2) Backlighted display
(3) Convenient form factor, and it has a fold out stand, which I find necessary.
(4) Compartments for either AA or 9V batteries are a nice touch, as is the hatch on top to stow the probes and cables.
(5) The display is clear and easy to read, although it provides limited visibility when viewed from above at an angle of perhaps 60 degrees (it offers sufficient lateral visibility).
(6) Carrying handle is, well, handy.
(7) Measures capacitance and frequency in addition to the usual suspects
(8.) Auto-ranging
(9) Faux analog meter
(10) RS-232 port/cable to link with computer (some serial-to-USB adapters may not work with this device; this is typically a driver issue)

On the minus side:

(1) Insubstantial (cheesy) and unusable probes. These could even be a safety hazard around high voltages. I had a professional set on hand that I am using with the M9803R.
(2) No marker on the FUNCTION/RANGE SELECTOR knob, so you can tell which setting it's pointing to. I corrected this by daubing a line of red model paint in the appropriate groove.
(3) The beep, for making continuity checks, for example, is not loud enough!
(4) Tiny little Philips screw to access the battery compartment
(5) No auto shutoff
(6) "Chinglish" Users Manual -- One of my faves: "The Continuity Measurement is always fixed the range." Hey, Honey. I fixed the range! When's supper?

also here it is the source code for the uart RS232 interface
http://sourceforge.net/projects/mmeter-read/



the price seems good, what do you think about ?
Logged

Pages: [1]   Go Up
Jump to: