USB-6251 BNC Wiring Problem with Analog Input / Drifting Voltage

[xcvb1]

Hi everyone,

im trying to measure an analog voltage from a sensor with a USB-6251 BNC DAQ Board.

When measuring the signal in LabVIEW Signal Express the voltage is slowly increasing over time (=voltage drift?), so I think my wiring is probably wrong.

I attached the current wiring. The 5V Sensor is connected to a coupler which is then connected to a 24V power supply. The sensors ground is connected to the ground of the power supply (according to the data sheet), so I chose "Ground Ref. Signal" on the USB-6251 and used "Differential" Measurement.

Is there anything wrong with the wiring? Do I need to connect the grounds of the Power Supply and the DAQ? Both are connected to the same socket.

[n_dakota]

Hello,

Did you manage to solve this problem? According to what you described below, I was not able so far to identify the issue, but maybe you have some more hints in the meantime 🙂