Micromod RetroPAK: SLC Configuration Manual - Manual (Page 107)

Pre-configured Dual Loop PID Control
GENERAL DESCRIPTION
The advanced PID controller function code implements a proportional integral derivative
controller.
This control strategy has two independent loop compounds (SINGLE LOOP
CONTROL 1 and SINGLE LOOP CONTROL 2) each with PID loops with local
setpoint, I/O and other function blocks.
UTILIZATION
Both the loop compounds have the function code compound FC156 – PID. This is PID
with Local SP and uses a PID block, PAD (Process Alarm Display) blocks and a variety
of other blocks to perform a full-pledged PID with PV and Local Setpoint. The PID is
advanced with feed-forward control, bump-less transfers and other features.
Load the loop compound at the top level (where the IF, DIF, SE and ST blocks are
located) of the function block diagram.
The built-in input 1 (AIN1) and built-in output 1 (AOUT1) are used in the first loop and
built-in input 2 (AIN2) and built-in output 2 (AOUT2) are used in the second loop.
Figure P2.1.
Dual loop
PID with Local SP
P2- 1