VisiLogic versions older than 4.00 contained a PID function. This function has been replaced by the PID FB, which offers Auto-tune plus other advanced operations.
If you open a project which implemented PID using the older PID, you will receive the following error message:
"This project contains X number of outdated PID loops. Using outdated PID limits you to 4 PID loops. For more information, please click on the Help button below."
Although older projects will function, it is recommended that you update these projects, replacing the PID function with the PID FB. Please note that V120-12 continues to support the older PID function, continues to support up to 18 PID loops, but does not support the PID FB.