Hello Jerome,
Is this offset on an AI line or AO? If it is on an AI line, do
you see an offset when you connect a signal to the channel? How
are you measuring the channel offset? When nothing is connected
to an AI channel, the line is floating, so the channel could read any
voltage because it is not referenced to anything. This is only
problematic when that offset continues to be applied when a signal is
attached to the line.
If you see an offset after attaching a known voltage, you may have to calibrate your device. Here's the a page with
calibration information or you could send it into
National Instruments for calibration.
Regards,
Micaela N
National Instruments