Acquisition using PCI-6025E yields undesired additional voltage offset

[LabVIEW, Multifunction DAQ and CAN]

I want to acquire the ouput voltage of an Instrumentation Amplifier using PCI 6025E card and LabVIEW

But It reads a value which is much higher than the actual value. (ex. 5.23V for 1.20V)

But I am able to read the voltage with multimeter correctly.

Kindly suggest a solution.

[Tiptop]

Hello!

Here are a few of the common problems that I have seen.

1.) Check that your terminal configuration is set correctly. Differential vs. RSE.
2.) Check a battery and see if it reads correctly. If a battery works, then you probably have a problem with source impedance. The source impedance of your amplifier should be less then 1k ohm.
3.) If a battery will not read correctly, then it is time to start looking at the cabling, and terminal blocks for problems. You may want to check and make sure none of the pins are bent.

Let us know if this does not solve the problem!

Justin

[Tom_W_[DE]]

Hello-

Can you please let us know a bit more about how you're configuring your tasks and connecting the signals?

Are you using a differential connection or grounding one of the pins (i.e. RSE as suggested by TipTop)?

Also, are you creating the tasks/channels programmatically or in MAX? Also, do you see the same behavior in Test Panels in MAX?

Any insight into the connections and how you're measuring them would be helpful in troubleshooting the problem.

Thanks,

[LabVIEW, Multifunction DAQ and CAN]

Thank for ur response and here are the details

i have configured a virtual channel in using MAX and is in differential mode.

I have checked it in Test Panel of virtual channel but to read a voltage with a DC drift.

has it got anyrthing to do with the source impedence?


Please let me know the maximum source impedence to a Channel in differential mode.

I found no impedence matching specifications of PCI-6025E card.


Thank U.

[Tom_W_[DE]]

Hello-

It could be possible that the source impedence is an issue. The low-impedence line value is considered as approximately 1kOhm. Have you had luck in measuring a battery as suggested by Tiptop?

Thanks,