Program a Function Block Diagram
20 Rockwell Automation Publication 1756-PM009G-EN-P - February 2018
This prevents the operator from ever putting the Totalizer into Program
control by setting the OperProgReq input from an operator interface device.
Likewise, constantly setting the ProgProgReq input can "lock" the
instruction into Program control. This is useful for automatic startup
sequences when you want the program to control the action of the instruction
without an operator inadvertently taking control of the instruction. In this
example, the program sets the ProgProgReq input during the startup, and
clears the ProgProgReq input once the startup is complete. Once the
ProgProgReq input is cleared, the instruction remains in Program control
until it receives a request to change. For example, the operator sets the
OperOperReq input from a faceplate to take control of that instruction. This
example shows how to lock an instruction into Program control.