PXIe 4300 with TB-4300B reads low.

[Roese]

I am using a PXIe 4300 card with the TB4300B terminal block. I am trying to read voltage around 250V on two channels and voltages aroun 5.6V on three channels.  The 250V measurements are pretty close, however the channels where I'm expecting measurements of 5.6V, I'm only reading 4.0V to 4.5V.  I've verified the 5.6V with an external DMM, and they measure correctly (5.6V).  On the TB 4300B, I've connected the AI- and the COM for each channel.  Is there a problem with measuring high voltages and low voltages on the same card?  Any suggestions would be appreciated.

[Kimchi-Taco]

Have you tried a self-test and calibration?

[Roese]

Yes.  I think my problem is acutally the input impedance is too low on the TB 4300B for my measurements

[Kimchi-Taco]

Can you try to measure the 5.6V separately without the 200V so you can see if that has any affect on it?