Why does LabVIEW skip over commands in programming structures

Hello everyone!
Is there a certain way you program to make labview execute ALL commands within a loop before going into another loop? For example, I have a while loop that stops if either the stop button is pushed or if the set point input is greater than 8. If both of these are false, then the code entered a case structure where it controls the output from a plant model. However, labview will enter the case structure without checking if both conditions are met. I've attached the VI and in the next message will post the VIs from the plant. I want it to do the below code,
IF (Set Point > 8 OR Set Point < 0) THEN
SET_Point OK= False
ELSe
SET_Point OK = True
END IF
IF (SET_Point OK = FALSE OR Stop Button pushed) THEN
! STOP VI
ELSE
! Enter PID Control Loop
END IF
But labview likes to just jump around and skip parts for some reason. So when it for example, skips the OR check it uses the default value of true for the next case structure. It's driving me crazy. Can anyone please tell me why its doing this??
Thanks.
Solved!
Go to Solution.
Attachments:
General Auto PID Simulator.vi ‏83 KB
Global 1.vi ‏5 KB

Ah! I can't believe I made that dumb of a mistake. And thanks for the advice altenbach. My overcomplicated diagram probably lead me to making that error.
I have another question though. How come when I use the Write to measurement file VI it will start the process variable at like 40 inches but when I don't use it, it'll start it at 0 and do as its supposed to? I've attached my updated VI with the write to measurement file VI in it. You'll see that if you delete it then it'll do as its supposed to. I don't understand why though..
Attachments:
General Auto PID Simulator.vi ‏118 KB
Global 1.vi ‏5 KB
problem with PV initialization.JPG ‏132 KB

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dav2010 wrote:
I was building a case structure with an array of strings. So, I copied the strings from the array on the FRONT PANEL directly into the SELECTOR LABEL. My 3 strings have the form; to me, these are 5- character strings with spaces, or 7 characters if you count the spaces as string characters
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