SbRIO Hangs after a random Time !!

Question

Dear All
I hope my message finds u well
I am working on a project based on a sbRIO 9641 with an SD C series NI 9802 Module used to securely log data to it
the point is that the sbRIO is used to control a Temperature/Humidity chamber by it's Industrial DO which is connected to relays and contactors operating certain HVAC components (e.g. compressors , heaters , boilers..etc)
the problem is that after a random time (sometimes 10 minutes , 1 hour , 5 hours ) my Host VI seems to feel nothing from the RT VI and the Temperature and humidity readings sent from the RT VI to the host seems to become constant , the DO hangs and the whole target acts as it is freezed !
I kept searching for posts related to RT hangs and found some issues related to File IO with timed loops , so I'd like to clarify that all the loops are While loops , and I am logging a Datalog file to the SD card.
Also I'd like to add that the Library holding the shared variables is at the host , if this may make any problem
I monitored the CPU usage and memory of the target using the System manager, and seems everything is normal (sometimes CPU reaches 75% )
I'ts been a while trying to find our a solution or a clue for this problem , I hope anybody can help since this is very critical 
Thanks in advance
Eng. Mohammed Ashraf
Certified LabVIEW Associated Developer
InnoVision Systems Founder, RF Test Development Engineer
www.ivsystems-eg.com

Answer 1

Hey Mohammed,
        First off, the Library holding the shared variables should be located on the host as you have it. Next, when you say that the DO hangs what do you mean? Does it simply stop outputting all together or does it output a constant value? And is it possible that your VI and target are losing communication? If you check the Distributed System Manager (DSM), found by selecting Tools >> Distributed System Manager, are the network published variables that you're using to send values from the target to the host still changing? The DSM will display the current value of the variables. This will tell us if the variables are updating and simply not being displayed by the host, if they're staying constant, or if they're not updating because the host has lost communication. Also, once the DO "hangs" can you still communicate with the device in Measurement and Automation Explorer? These steps will help us narrow down the possible causes of this behavior. Have a good evening!
--Ryan S.