Fast readout Agilent 34411A/34461A

[plesa]

There were discussion about speed of measurement on Agilent 34411A/34461A in 34461A thread.
I made investigation and the 34411A is capable to provide 50k samples per second via ethernet. In the measurement are small gaps. The gap size should be reduced by program optimization, I suppose.
If there is anyone interested in Labview  program, let me know, I will build it and post it. The switching off or on display does not have the speed measurement impact.

[Sparky]

Hi plesa:

I would be interested in seeing a LabView program, but it would be much better to read about how you achieved the high measurement rate and data transfer. 

If you can share details e.g. which SCPI commands and parameters, and how you go about taking the measurements, e.g. how frequently polling the instrument, and how many reading to request at a time, it would be very helpful for those who would like to develop their own computer programs.

Did you have to do anything specific to get high sample rate that is not mentioned as "tips in the footnotes" in the 34411A user's guide??

[plesa]

Hi plesa:

I would be interested in seeing a LabView program, but it would be much better to read about how you achieved the high measurement rate and data transfer. 

If you can share details e.g. which SCPI commands and parameters, and how you go about taking the measurements, e.g. how frequently polling the instrument, and how many reading to request at a time, it would be very helpful for those who would like to develop their own computer programs.

Did you have to do anything specific to get high sample rate that is not mentioned as "tips in the footnotes" in the 34411A user's guide??

There were few issues to achieve the fast reading rate

Following VISA SCPI commands
:CONF:VOLT:DC 1,0.00001
:VOLT:DC:NPLC 0.001
:TRIG:COUN INF;
:SAMP:COUN 10000;
:TRIG:DEL 0
:TRIG:SOUR IMM;
:ZERO:AUTO OFF;
:FORM:DATA REAL,64;
:FORM:BORD NORM;
:INIT;
:DATA:POIN? RDG_STORE
For reading I'm using R? command several times to ensure the buffer in empty
In Labview I canot use directly save data to. csv file  due to the speed limitation, the data are stored by TDMS in Labview and after reading is finished converted and saved to .csv file
In attachment is application working with 34411A ( 52k readings/s and 34461A 1120 readings/s achieved with 0.5 input voltage.
To run the application you will need to install also Labview Runtime Engine.

If there will be demand for proper application I will rewrite it in C#. The Labview is handy fo FFT analysis ( mentioned on http://gpete-neil.blogspot.cz/2012/02/using-dmm-as-dynamic-signal-analyzer.html )

There is already a thread about this: https://www.eevblog.com/forum/testgear/new-agilent-34461a-6-5-digit-bench-multimeter/

Yes, but is is slightly off topic, it is more related to 34411A and not 34461A

[Sparky]

There were few issues to achieve the fast reading rate
<snip>
For reading I'm using R? command several times to ensure the buffer in empty

If there will be demand for proper application I will rewrite it in C#. The Labview is handy fo FFT analysis ( mentioned on http://gpete-neil.blogspot.cz/2012/02/using-dmm-as-dynamic-signal-analyzer.html )

Thanks plesa!  I had a quick test of your program using my 34461A and it worked fine over LAN --- your LabView application showed just over 1kSamples/sec were acquired.  Only thing that didn't work was saving CSV file to C:\ (because no write access) but if I ran the application with "Admin Privileges" it probably would have worked.

Yes, the LFA shown on the blog you posted is very neat!  I will eventually try with my 34461A when I have some time to play!  Your notes will come in handy, and I would like to attempt to write a portable (compiled) MATLAB application for it.  I'm not so familiar with LabView.

Thanks again!