Agilent 34401A multimeter to PC with Labview driver via RS232

[Yulia]

Thanks for the response! I have Labview 8.2.

Here is the current situation: I downloaded the file hp34401a.zip, unpacked it to the Program Files/National Instruments/Lbview 8.2/instr.lib, after that I went to this folder, opened HP34401A Initialize. VI, put COM1, it didn't give me an error message. After that I opened HP34401A Single Read Example.VI, also no errors, but no measurements as well, when I am trying to close this VIs it gives me messages about saving (please,see attached). 

Should I get rid of this folder with the driver? Where I can find the VIs associated with this DMM?

[Yulia]

If I am disconnecting the instrument (unplugging RS232), these Initializing and Single measurement VIs look the same  way as with cable plugged in.  

[Dennis_Knutson]

Why should anything change? It does not matter how the VIs look statically. It only matters when you actually click on on the run button. NOTHING matters at this point except actually running the VIs.

The current driver for the 34401 is a project style driver and is located here. The examples show up in Help>Find examples. If you did not delete the driver that came with LabVIEW, try using that.

p.s. this all a bit confusing to me when you say you get an error and then a short time later, say you don't.

[Yulia]

By ''...VIs look the same...'', I mean when I press run button, they behave absolutely the same way, no matter, if RS232 with DMM is connected or not, which makes me think there is something really wrong with this thing. 

I was saying about the error, because I had it, when I was running VIs without changing to "COM1", these errors are my fault, sorry for the confusion.

Thanks again!

Yulia.

[ian_fung]

Sorry for interrupting...

Since you are Communicating with Agilent Instruments using RS-232, this might be of helpful in one way or another.

http://www.home.agilent.com/agilent/editorial.jspx?lc=eng&ckey=558637&id=558637&cc=US

[Dennis_Knutson]

Please, just stick with runnig the initialize function. Open the block diagram of it and probe the output of the VISA Read. See what is returned.

[Yulia]

Hi! Thanks! I downloaded this driver, unziped it to the Labview/inst.lib, run Initialize.VI, probed the "errors out", no errors.

But, when I am trying to take a single measurement with Read Single Measurement.VI, there is 0 at the field for the measured value. I am just taking DC voltage from the battery.

Yulia.

[smercurio_fc]

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@Yulia wrote:

Hi! Thanks! I downloaded this driver, unziped it to the Labview/inst.lib, run Initialize.VI, probed the "errors out", no errors.

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Why are you doing this????????????????????

LabVIEW already comes with the driver for the 34401 and this has been stated multiple times!

[Dennis_Knutson]

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@Yulia wrote:

Hi! Thanks! I downloaded this driver, unziped it to the Labview/inst.lib, run Initialize.VI, probed the "errors out", no errors.

But, when I am trying to take a single measurement with Read Single Measurement.VI, there is 0 at the field for the measured value. I am just taking DC voltage from the battery.

Yulia.

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I did not ask you to probe the error out. That would be silly since it is an indicator. What I asked you to do was to probe the output of the VISA Read, as shown below.

This is to covince you (and me) that there is two way communication between LabVIEW and the instrument. Troubleshootin is a stp by step process that it seems you are not to willing to follow. Once you have verified that you can read the id, then you can troubleshoot the reading. I would suggest setting a breakpoint on the read function. Then go to local mode on the 34401. See if there is a reading. Continue execution of the VI.

[Nirmal77]

hi...i am doing project of calibration and verification of 4-20mA systems using LABVIEW.For calibrating i use analog io card with agilent 34401A multimeter.I want to know how instrument drivers for agilent 34401A are used in labview.How we control the electrical quanties with these drivers.If you have any files relating instrument drivers please send to me.