Allen-Bradley Micro800

Proportional Integral Derivative (PID) instruction Chapter 20
Rockwell Automation Publication 2080-RM001D-EN-E - February 2015 569
This section provides specific details and examples for using the proportional
integral derivative instruction, including the following:
Example: How to create a feedback loop for the manipulated value on page
578
Example: How to implement auto-tuning in a IPIDController function block
on page 569
Example: How to add a UDFB to a PID program on page 579
Using auto-tune with the IPIDController function block
You can use the AutoTune parameter of the IPIDController function block to
implement auto-tuning in the control program.
Auto-tuning requirements and recommendations
Following is a summary of requirements and recommendations for implementing
successful auto-tuning.
• Autotuning must cause the output of the control loop to oscillate, which
means the IPIDController must be called frequently enough to adequately
sample the oscillation.
• The IPIDController instruction block must be executed at a relatively
constant time interval.
• Configure the scan time of the program to be than half of the oscillation
period.
• Consider using a Structured Text Interrupt (STI) instruction block to
control the IPIDController instruction block.
Using the Proportional
Integral Derivative
instruction