I wish to program my mass flow controller through labview

[manish]

I wish to control relative humidity of air by controlling the flow of dry air which is mixed with a fixed flow of high humidity air. I wish to make this application using labview which would read the current relative humidity of air, compare it with my required humidity, and send command to mass flow controller to control the amount of dry air which when mixed with humid air would result in required humidity.

[Russ@Davis]

You should be able to meet this objective -- however, your going to need to be a little more specific with what you have (hardware) and what the issue is.

[Jeremy_C]

Manish,

Russ is correct. You should be able to accomplish this in LabVIEW. What you described sounds like a simple control loop. Below is an example of a basic PID control loop that acquires some data, analyzes it, then outputs an appropriate value depending upon the input. This is a good starting point for your application.

PID example