I would like to measure continuous low voltages (about 0.1 mV) using the pt104.
If I connect (short-circuit) pins V+ and ground (single ended mode), I read a value around -0.02 mV, using picolog recorder.
When measuring a low voltage, the value is 0.02mV under the value given by a multimeter.
The value 0.02 mV is not really constant so that I cannot just add it to get the real result.
I have tried using the differential mode by connecting (short-circuit) pins V- and ground. The error on the value given by the multimeter is then between -0.01 mV and 0.01 mV, with high frequency variations.
What can I do to get the real value?