Measuring the one sensor above and one sensor below

Question

Hi
Cn somebody help me in measuring one sensor above and one sensor below and if thy are almost equal must stop.
I tried doing so, but i dont knw whr it is going wrong. I hv attached the program with this query.
In a large cryogenic storage system,  we need to find the level of cryogenic fluids. For ths we a immersed PCB consisting of multiplexers and sensors into the storage system. We need to find the level by passing current to the PCB & measuring voltage at each sensor. We can conform the liquid level by measuring one sensor above and one sensor below the actual level.
Thanks in Advance.
Regards,
Sujeep. 
Attachments:
liquidlevel1.vi ‏358 KB

Answer 1

sujeep wrote:
Hi
Can somebody help me in measuring one sensor above and one sensor below and if they are almost equal must stop.
I tried doing so, but i don't know where it is going wrong. I have attached the program with this query.
In a large cryogenic storage system,  we need to find the level of cryogenic fluids. For this we a immersed PCB consisting of multiplexers and sensors into the storage system. We need to find the level by passing current to the PCB & measuring voltage at each sensor. We can conform the liquid level by measuring one sensor above and one sensor below the actual level.
Thanks in Advance.
Regards,
Sujeep. 
You should submit a little more detail as to what is going wrong.  Also, what do V1 through V6 represent?  They seem to be read from the same analog input channel.  You should try passing those value through with wires rather than using local variables.  If so, you could eliminate a large number of your sequence frames.
In the 4th frame of your sequence structure, you could have a race condition.  You are reading V4 as a local variable around the same time you are assigning a value to V4 through the DaqMX read.  You don't know whether it is using the latest V4 value or the one from the previous iteration. 
I would also recommend not using the STOP sign VI.  If you have a case where the program should end, you should wire the boolean out of the case structures and to the condition node of the while loop.  It will allow the code to end much more cleanly.  In your situation, the DaxMX close will never execute because the only way the program ends is through the STOP sign which is the equivalent of hitting the ABORT button.