I am using a NI DAQ-Pad 6016 to measure analog voltages on all 8 differential channels. Every once in a while I will only use one or two channels. But when I do that I always get a 5V signal on the unused channels. Can anyone explain why that is?
It is simple enough, however, to ground channels that would otherwise
be floating by simply shorting the positive and negative terminals of
the channel.
That's written in the document I was supposed to read and I have already done this. Why do I still get the 5V signal?
Shorting the positive and negative terminals together will only make them the same value. This value is still floating in reference to GND. I would tie them directly to GND since you are seeing this behavior.