Hello,
We are experiencing an issue with the measurement accuracy of the RPi expansion board
Eight 24-Bit Analog Inputs DAQ 8-Layer (SM-I-022), which is brand new, recently purchased. The board is powered by 12 V, and for testing we are measuring a voltage of 5 V.
Power Supply 12V:
Voltage 5V applied to inputs 7 and 8:
1.)
Testing input 7
Before connecting input 7, we read a value of
-0.000066. After connecting a 5 V input (+ and GND), we read a value of
3.686978 (difference
1.3130 V relative to 5 V).
2.)
Testing input 8
Before connecting input 8, we read a value of
0.000006. After connecting a 5 V input, we read a value of
3.690599 (difference
1.609407 V relative to 5 V).
Here is a snippet from the console:
The gain for both channels is set to 0. After running the calibration of input 7 at 5 V, the reading remains the same. I have updated the board’s firmware, but the results are still the same. This issue occurs on all inputs.
Could you advise what might be causing this issue?
Thank you,
Jan
