This is a very typical application for the Tstat10. There is a detailed description on how to build custom tables for inputs… found it:
After the input is configured you can create a setpoint in the variables, use the same engineering units for both: Pa or whatever it is you are using for pressure.
Then fill in both items into one of the PID controllers. Set the P term to perhaps 10% of full scale. Leave the I term and D term blank for now. After everything is set up you can come back and add some I term. You shouldnt need D term. There’s details on setting up PIDs in the T3000 help system. Hit F1 to bring up the help system.
Configure your output for the fan to 0-100%.
Once that’s done you write a short program.
FAN101 = PID1
You can include interlocks with the fan enable relay, schedule and so on once you have the basics going.
Add a trend log for all the ins, outs, vars in the system.
Create a graphic for the system for your user interface.
And that’s about it.