agilent 34410A

[alexgluc]

Hello,

I'm trying to record AC current measurements from my Agilent 34410A multimeter. I'm running the attached example I've found on the NI website. According to Agilent specifications I should be able to acquire up to 10000 readings/s @ 5½ digits. I want to continuously record data for a certain time, so I've selected the "Multiple Points" option in the drop-down menu of the example. I don't understand why, by the way, I can't get for istance more than 35 samples during 10000ms simulation. How can I increase the number of samples during the same amount of time, taking advantage of the multimeter capability? Is there any other VI program which works better or any possible way to better set up the following attachment?

If this helps: my visa resource is the USB one and the other parameters I'm using are those of the default (baud rate -9600, parity -even, bits -7).

Thank you in advance,

Alex

[NIquist]

You may be able to do better than you are but just because the DMM has a 10,000/s burst mode doesn't mean you can use it as a DAQ.  You'll have to get into the low-level VIs and configure the DMM very specifically to do what you want (The 34401 Instrument VIs come with LabVIEW in the Instrument IO > Instr Driver palette).  Plus, you'll be limited to your communication protocols speed so at 9600 BITS/s you'll get 1200 BYTES/s.  Depending on how many bytes it takes the DMM to transfer a 5 1/2 digit value you'll be limited further.  By the time you're down to what you can realistically expect you'll probably wish you just bought a cheap DAQ card.

[NIquist]

Here's an idea that might be a good way to determine the speed possibilities without too much trouble:

[From Agilent manual]

In the "talk only" mode, the Agilent 34401A automatically sends readings directly to the GP-IB or RS-232 port. To enable the "talk only" mode, first set the HP-IB address to "31" using the front-panel I/O Menu. Then, select either the GP-IB or RS-232 interface (also in the I/O Menu). For proper operation, make sure that your printer is configured for the "listen always" mode.

Set it for talk-only, then read the RS-232 port at high speed with LabVIEW.  You can play with the front panel controls and change the DMMs parameters trying to get the most bandwidth as you monitor results at your PC.  Don't forget to play with the VISA settings as well as that may be your primary bottleneck.  Good luck and let us know how it goes (that DMM is very popular so others may benefit from your experimentation).

[Oriol_G_L]

Hola, tengo el mismo problema

Intento configurar el Labview en "Listen Always" mode pero no encuentro la manera

Alguen puede decirme como?

Salutacionen y gracias.

Oriol

[funkytuqe]

I recently went through this same problem while trying to continuously sample the 34410A at it's Maximum 10k/sec.  I have found that it is entirely possible but you have to use the lower level VI's in the device driver.   Start with your initial setup of the instrument with the setup VI's first, make sure you set the proper NPLC for max reading speed.   The trick is in the low level Configure Multipoint VI, you can set up the desired sample interval there plus input the internal buffer allocation in the sample count (I just set it to the max 50k samples) .  However, the problem with that VI is that you can not set up the infinite trigger option (only 1-50000 counts, which ultimately ends the triggers and stops the meter), so after the Configure multipoint VI create a VISA write and send the ":TRIGger: SEQuence:COUNt INF" command. After that, use the initiate measurement VI to start the sampling, then place the fetch measurement VI in a continuous loop to send the readings to your PC.   I have had good success with this approach over GPIB, USB and Ethernet but I have not used the RS232.  I can event get the full 50k/sec using the 34411A.