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How to increase sample rate of Keithley 2000 multimeter

Hi,
  
   I am using Keithley 2000 meters and labview to measure and record my experimental data. They worked fine for general DAQ, however, one of my recent research projects requires fast sample rate, e.g. greater than 500 S/s. The maximum sample rate I can have now is about 4 S/s at 6.5 resolution using my current VI based on the modification of the original driver. The website claims it can collect up to 2000S/s at 4.5 digits. I tried to set the resolution at 4.5, but still I could not increase my sampling rate. I have attached a simplified VI where I have only one type of measurement. In my actual experiment, it may require up to 6 input signal, e.g.,Volt, current, or resistance, simultaneously . 
 
    P.S. I am using GPIB to USB cable for data communication. Sub VIs are included in the attachments as well.
 
   Thanks.
 
Andrew
 

 

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Hi Zhu,

 

the Keithley DMMs allow faster sampling when using their internal data buffer! There are special commands to configure that buffer and to fetch data from it.

It's all described in the K2000 manual, you only need to read it…

 

When it comes to aquiring 6 signals in different units (V, A, Ohm) the K2000 needs to switch inputs (do you have a multiplexer card built in?) and signal amplifier too. Both actions need their time (which is specified in the manual) and both actions will reduce your maximum sampling rate!

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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@AndrewZhu wrote:In my actual experiment, it may require up to 6 input signal, e.g.,Volt, current, or resistance, simultaneously .

I would recommend going to a DAQ card then.  You will need to do some circuitry to get all of those types of measurements, but it shouldn't be anything major.  And then you can sample a lot faster than the Keithley 2000 and have the data logged straight to disk as a TDMS file.


GCentral
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