Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller FLEXIBLE CONTROL STRATEGIES - Manual (Page 173)

A.1.10 CS41 - FOUR-LOOP CONTROLLER
The four-loop controller provides four independent PID controllers. Loading CS41 initializes the
ANI1–7 engineering spans to 100.0, and the display list is modified to the four-loop sequence. The
control scheme is shown in block diagram form in Figure A–10. Also provided is Table A-10, which
is a worksheet that shows the CS41 wirelist connections; wirelist datapoints not connected are left
at default. Table A-10 is partitioned by FCS module type applicable to CS41 (those modules in Fig-
ures 2-1 through 2-3). The datapoint parameters for each module are shown with their default val-
ues.
The following I/O assignments result from loading CS41:
ANI0 Process Variable Loop 1 CCI0 Remote Setpoint Enable Loop 1
ANI1 Process Variable Loop 2 CCI1 Remote Setpoint Enable Loop 2
ANI2 Remote Setpoint Loop 1 CCI2 Remote Setpoint Enable Loop 3
ANI3 Remote Setpoint Loop 2 CCI3 Remote Setpoint Enable Loop 4
ANI4 Process Variable Loop 3 CCI4 Force Fallback Loop 1
ANI5 Process Variable Loop 4 CCI5 Force Fallback Loop 2
ANI6 Remote Setpoint Loop 3 CCI6 Force Fallback Loop 3
ANI7 Remote Setpoint Loop 4 CCI7 Force Fallback Loop 4
ANO0 ControlOutput Loop 1 CCO0 Process Alarms Loop 1
ANO1 ControlOutput Loop 2 CCO1 Process Alarms Loop 2
ANO2 ControlOutput Loop 3 CCO2 Process Alarms Loop 3
ANO3 ControlOutput Loop 4 CCO3 Process Alarms Loop 4
Each loop contains an individual set of parameters that dictates its operation. This allows the loops
to be fully independent. The description that follows is for Loop 1, with Loops 2, 3, and 4 refer-
enced parenthetically.
The input/output configuration for all loops is the same: process variable, remote setpoint, remote
setpoint enable, control output, force fallback, and process alarms. Only the process variable and
control output signals are essential for standard loop control purposes; the other signals do not
have to be configured. Process variable ANI0 (ANI1, ANI4, ANI5) is the controlled parameter, and
control output ANO0 (ANO1, ANO2, ANO3) is the regulator signal. When a closed contact is pre-
sent on CCI0 (CCI1, CCI2, CCI3), remote setpoint selection is possible using the R/L push buttons.
When an open contact is present on CC14 (CC15, CC16, CC17), the output and setpoint are
forced to fallback values contained in the OTV and STV parameters of the CON modules when the
applicable enabling parameters are set. While remote setpoint is selected, the control setpoint
value is obtained from ANI2 (ANI3, ANI6, ANI7). Whenever an alarm condition associated with the
control loop occurs, the contact CCO0 (CCO1, CCO2, CCO3) is closed; otherwise, the contact is
open.
Appendix A. Control Strategy Wirelists
4110-TXT
A–83