PCI6704 incorrect Voltage output

[william879]

Dear all,

I am new in labVIEW. I am trying to generate a DC voltage output from our PCI 6704 card by testing with MAX and DMM. There is always a varied offset between input and the actual VOLTAGE output. Current output seems fine.

For example:

Input-------------------Output
  0V ------------------- 0V
  1V--------------------1.012V
  2V--------------------2.02V
  3V---------------------3.04V
               ......
  After the input beyond 5V,
  5V---------------------5.4V
  6V---------------------6.6V

At 10V input,  output is 11V (I know it is not suppose to go beyond 10.1V, but it does)

This thing is driving me crazy, since it is a brand new card. there should not be anything wrong with it.

Is it the problem with my DMM? I will try to get another one to test tomorrow.

Anyone had the similar experience? or know the answer? PLEASE ADVISE!!!!!!!!!!!!!1

William

[hoffiz]

Hi William,

Make sure you are connecting the DMM to the correct PIN, for example if you are using AO 0; you are going to connect the DMM to pins 34 and 68 as seen in the manual for the PCI-6704 (page 12). Second, make sure that when you are measuring the voltage you are not using the ground of that channel for current output just for now while we are testing the card with the DMM.  I would like to know the manufacturer and model of your DMM just make sure it is precise enough to give you a good reading.  Can you try more than one channel and check if you get the same response?  After trying all the suggestion I have already gave you, you might consider calibrating the card. I know it is a brand new card but it is possible that we need to follow this step.