RS-232 for reading analog voltage

[Amanda2482]

Hello,

I am trying to read an analog input of 0-5V from my flow meter, Omega FMA-1605A. I connected the communication wires to the RS-232 port on my USB to RS-232 adapter that is connected to the computerw. But when I try to set up a DAQ read task, it says "No supported devices found."

What can I do to fix this? Should I try using the PXI-6239 card I am using to read analog current signals to read the analog voltage?

Thank you!

Amanda

[Dennis_Knutson]

DAQ has absolutely nothing to do with serial communication. You should be using the VISA functions. There are some shipping examples that you can use for a starting point. I would recommend you first use a terminal emulation program such as hyperterminal, putty, etc. to debug the communication and verify com port settings, commands, and cable type.

p.s. In the future, use the Instrument Control board.

[crossrulz]

If you want to use a DAQmx task, then you have to use an NI DAQ device.  A simple one like this might work for you: USB-6000

[TBirkulosis]

You can use the NI-VISA driver to communicate with the Omega device via RS232. Serial communication works by sending device-specific commands. The commands are likely listed in the Omega device's manual. The PXI-6239 is an analog input module, so you can wire signals into the channels. I'm not familiar with the Omega device, so I don't know is it has analog output channels to input to the analog input channels on the PXI board. Most likely you will be using NI-VISA to send and receive messages with the Omega device.