Device/Sensor acquisition and control

[wew044]

Hi Ni Experts,

I would like to do the following control with LabView:

pressure sensor signal -> computer labview -> signal out -> valve control.

I know that if everything is bare wire, the communication is pretty straight forward. Use an IO module, plug pressure sensor to input, and valve to output and its pretty much set. 

However, what if their connections are different.. say if the pressure sensor has usb-rs485 connection, while the valve has bare wire.

I could plug the pressure sensor directly to the computer, and use an output module to connect to the valve, but then these devices will not be able communicate right? I am very confused about what is correct way of getting devices of different connections to talk to each other, if anyone could shred some light on this I am highly appreciated.

Thanks!

[nanocyte]

Yes, you need some glue to bring everything together. The glue of choice on this board would probably be a CRIO chassis. That could bring in either your 485 signal or your bare wire signal. From there, you need to program application logic that compares your pressure variable to the set point and sets the output.

[wew044]

Thanks for the reply!

If I understand your explanation correctly, it is OK that that the devices are connected to different DAQ modules as long as there is a chassis to combine them into one unit?

I have attached an rough sketch example, if you could take a look that would be great.

Thanks!

[nanocyte · Accepted solution]

Close. For your chassis, lets say we put a NI cRIO-9063 there. The 9871 would just drop in (no Ethernet needed). Now for your valve control that depends on your valve. You might be able to use an industrial output controller like a NI-9472. For your valve reader, you could use a NI 9202 or a 9381. I'm not sure how many channels or what voltage ranges you need to take in though.

Each of those modules drops in the 9063 and that's where you program your application and the logic of how the inputs relate to the outputs and the user interface, etc.