04-12-2020 05:07 AM
Hi all,
For a project I am using an external power supply for powering 16 sensors, either digital or analog.
This power supply is able to supply a voltage of 5V and 12V, and both have a seperate ground (dont ask me why they have 2 grounds, but here is the external power supply: https://nl.rs-online.com/web/p/embedded-switch-mode-power-supplies-smps/7066195/ ).
I am making a connector board PCB to power all sensors (mostly 5V) in a parallel circuit. The sensor signal from this board go to a NI-USB 6211 DAQ card.
My questions:
- How should I connect the ground of the DAQ card to the PCB?
- Do I need to do this for all AIGND/AOGND/DIGND/DOGND, or is one enough?
- Because there is one sensor that needs a 12V supply, do i need to connect the DAQ to a different GND for this one?
Thanks in advance!
05-27-2020 08:48 AM - edited 05-27-2020 08:52 AM
Hello Bryan_1995,
The connection depends on sensors specifications but try to separate digital sensors "D_GND" and analogue ones "A_GND" so connect them with appropriate terminal of DAQ.
I recommend you to check if the output and GNDs of the power supply are isolated or not. I haven't find info on the seller web page you shared but you can connect with the manufacturer to check the info.
Additionally, I recommend you to put low pass filters in power lines of sensors as digital ones may produce noise and effect on analogue sensor's readings.