RSLogix 5000: PIDE - Function Block Enhanced PID.

PIDE - Function Block Enhanced PID

This technote demonstrates the use of the PIDE function block instruction.
It uses two modes of automatic operation: program setpoint and operator setpoint.
To toggle between program setpoint and operator setpoint simply toggle the ProgOperReq bit in the PIDE instruction which is accomplished with the PROG_MODE_1 bit in the Main Routine.
When in program mode it gets the setpoint from the SPProg word in the PIDE instruction.
When in Operator mode it gets the setpoint from the SPOper word in the PIDE instruction
To toggle between automatic and manual mode simply set the ProgramManualReq bit and clear the ProgAutoReq bit in the PIDE instruction which is accomplished by toggling the AUTO_1 bit in the Main Routine.
The CVEU will track the value at CVProg when in manual mode
This Project has 3 tasks:

1. Main Task:
   The Main Task allows the user to set bits and put the PIDE in Program mode, Operator mode , Manual mode and to use Independent or dependent gains.
2. PID_Functions:
   The PID_FUNCTIONS task is a scheduled task that executes every 100 mS.   It contains the PIDE function block instruction and it has a task called Proc_lag which contains function block instructions that lag the PV from the CV to simulate a process variable.  
3. SETPOINT_GENERATOR:
   The SETPOINT_GENERATOR scheduled task executes every 10 seconds.  It simply changes the program setpoint every 10 seconds with the FAL instruction.  The setpoints are contained in the tag ARRAY1 which are 10, 15, 20, 30, 40, 60,80, 70, 50, and 30. 

The .ACD file is Called PIDS_FUN_BLK_DEMO and is attached below

This .ACD file was created using RSLogix 5000 ver 8.02 and a 1756-L1 firmware ver. 8.20.   It requires no I/O modules.

File Attachments

• PID_FUN_BLK_DEMO.ACD (105.88 KB)

Source : http://rockwellautomation.custhelp.com/app/answers/detail/a_id/20410