capturing pop off pressure of a relief valve

[Inexperienced]

I am new to Labview and would like some help getting started. I have an application that will pressurize a relief valve up to 500 psi. It is supposed to pop around 454 psi. We would like to capture the actual pop off pressure and reseal pressure. Mathmatically this should be the point at which the slope of the pressure curve changes. I would also like to make the program an executable so the user just clicks an icon on the desktop and it starts up automatically. I have attached the VI I have built so far. The following is how we expect it to execute. My boss is on me to get this done. Any help or suggestions anyone can give me would be greatly appreciated. I am using Labview 7.1 with a PCI 6259 card.

Relief Valve Test Assembly Operating Sequence

1. Click on Icon on Desktop to start VI.
2. Click on Start button to start sequence.
3. Ask for user name and save to file.
4. Check safety switch inputs are made and constantly monitor them
5. While safety switches are made energize high-pressure valve to increase pressure slowly to test fixture.
6. Average slope over 5 to 10 test points
7. Capture value at which average slope changes above 300 psi if new slope is maintained for 500ms. This is
the pop off pressure.
8. Flow rate sensor (to be added later) will capture the average flow rate at this point
9. Close high-pressure valve.
10. Capture value where average slope is near zero for 500ms. This is the reseal pressure.
11. Open exhaust valve for 1000ms
12. When operator clicks “SAVE PRESSURE POINTS” the two captured values are appended to the file that the user
name was saved in and the date and time are added. This file is maintained for all tests until file size
exceeds 10 kb.
13. When the operator clicks “SAVE ALL DATA” all the collected test points for the test are saved to a new file
with the operator name, date, and time.
14. If the operator clicks on “START” the sequence returns to step 3 to start all over again.

[AlanArmstead]

Hello,
You might want to take a look at some of the templates built into LabVIEW. Go to File>>New, then navigate to VI From Template>>Frameworks>>Design Patterns. You might want to check out the User Interface Event Handler if you want your program to act more event driven, based on button clicks or other user actions. Also, you might look at the Standard State Machine if you want your program to be more of a state machine architecture.
-Alan A.