Allen-Bradley Micro820 User Manual

164 Rockwell Automation Publication 2080-UM005B-EN-E - March 2015
Appendix D IPID Function Block
IMPORTANT
User Program Scan Time is Important
The autotuning method needs to cause the output of the control loop to
oscillate. In order to identify the oscillation period, the IPID must be
called frequently enough to be able to sample the oscillation adequately.
The scan time of the user program must be less than half the oscillation
period. In essence the Shannon, or Nyquist-Shannon, or the sampling
theorem must be adhered to.
In addition, it is important that the function block is executed at a
relatively constant time interval.

Allen-Bradley Micro820 Specifications

General

Processor	32-bit
Power Supply	24V DC
Programming Software	Connected Components Workbench
Series	Micro800
Mounting	DIN Rail
Memory	Embedded
Expansion	Yes
Controller Type	Programmable Logic Controller (PLC)
Communication	Ethernet/IP
Programming Language	Ladder Diagram, Function Block Diagram, Structured Text
I/O	Embedded