Micromod RetroPAK: SLC Configuration Manual - Manual (Page 147)

Pre-configured Dual Loop PID with Remote SP
GENERAL DESCRIPTION
The advanced PID controller function code implements a proportional integral derivative
controller.
This control strategy has two independent loop compounds (SINGLE LOOP 1
REMOTE SP PID and SINGLE LOOP 2 REMOTE SP PID) each with PID loops
with remote setpoint, I/O and other function blocks.
UTILIZATION
Both the loop compounds have the function code compound FC156 – PID with Remote
SP. This is PID with Remote 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 Remote
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. The
built-in input 2 (AIN2) is used as the remote setpoint input for the first loop.
A module input (VCIM1) and the built-in output 2 (AOUT1) are used in the second loop.
A module input (VCIM2) is used as the remote setpoint input for the second loop..
Figure P4.1.
Dual PID with
Remote SP
EXPLANATION
Configuration with this compound requires understanding of the compound and how the
PID block is configured in the MOD 30ML/Modcell controllers. Following is the
P4- 1