Data acquisition with Agilent 34970A in LV8.2 using VISA

[Guybrush Threepwod]

Hello,

I am trying to acquire temperature measurement through a 4-W RTD with Agilent 34970A.
I want to get this measurements into LV8.2. I have installed the LV-drivers that comes with
the Aqilent DAQ-unit, but I can't get any of the examples to work. I have installes the NI-VISA
4.0 drivers and I find the VISA resource name ('ASRL8::INSTR') in my controller.

My Agilent 34970A is connected to my computer with an RS-232 through a USB2COM device (MosChip).
I've tried to run the VIs in the example, but no data appears...help 😕

mvh
Arild (.no)

[Dennis_Knutson]

Do you get any error messages or error codes? If so, what are they? Have you tried using Hyperterminal to talk to the instrument? You should be able to do that and send a *IDN? query. If that doesn't work, you should double check the com settings (baud rate, partity, etc.) and make sure you have the correct type of serial cable. The instrument requires a null modem cable with pins 2-3, 4-6, and 7-8 crossed.

[Guybrush Threepwod]

Thank you for Your answer!

I use a nullmodem cable, and I get response on the *IDN? query.

I use the HP34970A sample read thermocouple temp.vi.

First i go the errormessage 205 on the Agilent instrument.

225: Settings conflict: DMM disabled or missing
This command is valid only when the internal DMM is installed and
enabled. Use the INSTrument:DMM? command to determine the state of
the internal DMM.

Should the internal DMM of the instrument be turned on?

I tried to turn it on and i got error 305: Not able to perform requested operation
The requested operation is not valid for the specified channel. You may
have tried to a configure a channel for current measurements (valid
only on channels 21 and 22 on the 34901A module). Or you may have
tried to configure scaling on a module that does not connect to the
internal DMM.

I am trying (at first) to read temperature throug a 4W RTD, and I configure channel
101 (who correctly pairs with n+10=111).

I use 19200 baud, 8-bit, no parity for the COM settings.

-A

[Dennis_Knutson]

And what was the result when you issued the INST:DMM? query? If you didn't do that, then you should go to MAX (Measurement & Automation Explorer) and do that. If it returns "0", then issue the command INST:DMM ON. If the DMM is installed, then when you repeat the first query, it should now return "1". If it still reutrns "0", then issue the INST:DMM:INSTalled? query. If this returns a "0", then that means that your instrument does not have a DMM. The 34970 may be ordered without a DMM. If I remember correctly, it's option 01 to get the instrument without a DMM. You can look at the back of the instrument to see what options you have.

[Guybrush Threepwod]

Suddenly it worked! Don't know what I did wrong actually. Thanks a lot for the help!

[Akello]

I know this is an old thread but I was just dealing with this problem and your suggestion cleared it up in a jiff.

Just wanted to say thank you.

Yusif Nurizade