TB 4300, Connected to PXIe 4300, Measurement issues

[cdialessandro]

Hi all,

I am trying to measure voltages using the cards mentioned above. This card has 8 channels and I am connecting them to a battery pack all connected in series. The issue I am having is that the first and last channels, channel 0 and 7 are reading low (approx 2V whereas they should be measuring 4.05 V). The other channels are all reading properly. I am sure that this must be a grounding issue but after many attempts of re configuring the grounding cables in different ways, the results are the same.

When using only 4 channels, ie channel 0 to 3, everything measure properly, it is only when I have all 8 channels attached that problems occur.

Any help is appreciated.

[rsmayer]

Hi,

Do you have any other way of measuring the actual signals being sent to the card? I'm wondering if the battery pack has enough power to supply for the 8 channels? I'm not sure why that would make channel 0 and 7 low though, it seems kind of random. How do you have the grounds hooked up currently?

-Ryan