Overflow is a condition where the input signal from the device under test exceeds the range or measurements capabilities of a particular instrument.
If you are encountering overflow, I would recommend increasing the range for that measurement to appropriately capture the desired reading.
If you find that overflow on a previous reading/channel is impacting the results recorded on a subsequent channel, I recommend checking the functionality of the channel against a known value (i.e. power supply static voltage source, resistor, etc).
If the channel is operating within specification, this may be an anomalous reaction to the overflow or could be due to a relative measurement configured via other settings of your test.
Can you elaborate on what you find when the values 'become large'?
This will help to better resolve the issue you're encountering. As much detail possible regarding your test, DUTs, settings and readings would be helpful.
