I need to load a file with pressure setpoints that will be sent out to a load cell

[Lab Student]

I have provided the user a way to select their pressure profile saved on the computer. The profile consists of pressure setpoints that they want to achieve on the load cell (i.e. a step function of pressure setpoints like 15psi for 20 seconds and then 35 psi for 20 seconds.....up to 150 psi). The pressure will be controlled by turning on or off a valve that allows gas to flow. I need to have a feedback loop that tells whether the pressure is at the setpoint and if not turn on the valve until it reaches that point. How do I load the file with the setpoints after the user has selected it?

[dan bookwalter]

what is the format of your file ?? can you attach a copy of your data file ?

Dan

[Lab Student]

Dan, thanks. Actually, the file consists of analog voltages between 0-5 volts. At this point I'm not sure how to construct the file or even how to send the voltage setpoints as I think about it. Basically, a transducer reads the pressure in terms between 0-5 volts and I need to be able to give it a setpoint from the file of say 1 volt monitor and make sure it stays there and if not send the a analog signal to a device that says open. Does that help any?

[dan bookwalter]

Take a look at the read from spreadsheet and write to spreadsheet.vi they should work for you... give it a try and if you still need some help i'll see what i can wire up for you... what version of LabVIEW are you using...

Dan

[Lab Student]

Dan, again thanks. Version 7.1 I'll take a look at the prescribed VIs and let you know. Thanks