From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.
We appreciate your patience as we improve our online experience.
Reading a flowmeter using an analog input modue is not
recommended or a good idea. It is possible but probably will not work
very well. My first suggestion would be to buy a counter module or a
digital input module. If you absultuely cannot do that then what you
should do is wire your flow meter to output a voltage within the range
of the AI module and connect them together. Then you will have to
constantly monitor the voltage to determine when it goes from "low" to
"high" signaling a pulse from the flow meter. You will also have to
account for all the spikes and noise your signal is bound to produce. I
would imagine that the time saved by purchasing a counter or digital
input module would offset the cost of writing the code to make the AI
module work correctly. Also, digital input modules are generally much
cheaper than analog input modules. I hope this helps and please
feel free to post any additional questions you might have.
Eric A. National Instruments Distributed I/O Product Support Engineer