Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller FLEXIBLE CONTROL STRATEGIES - Manual (Page 132)

A.1.6 CS20 - TWO-LOOP CONTROLLER
The two-loop controller provides two standard PID controllers in a single cabinet enclosure.
Loading CS20 initializes the ANI1 engineering span to 100.0 and the display list sequence to incor-
porate a second display group (CON1). The control scheme is shown in block diagram form in Fig-
ure A-6. Also provided is Table A-6, which is a worksheet that shows the CS20 wirelist con-
nections; wirelist datapoints not connected are left at default. Table A-6 is partitioned by FCS mod-
ule type applicable to CS20 (those modules illustrated in Figures 2-1 and 2-2). The datapoint pa-
rameters for each module are shown with their default values.
The following I/O assignments result from loading CS20:
ANI0 Process Variable Loop 1
ANI1 Process Variable Loop 2
ANI2 Remote Setpoint Loop 1
ANI3 Remote Setpoint Loop 2
ANO0 Control Output Loop 1
ANO1 Control Output Loop 2
CCI0 Remote Enable Loop 1
CCI1 Remote Enable Loop 2
CCO0 Process Alarms Loop 1
CCO1 Process Alarms Loop 2
Each loop has its own assigned individual set of parameters for operation control, allowing the
loops to be fully independent. The description that follows is for Loop 1, with Loop 2 referenced
parenthetically.
The input/output configuration for both loops is the same: process variable, remote setpoint, re-
mote setpoint enable, control output, and alarm status. Only the process variable and control out-
put signals are essential for standard loop control purposes; the other signals do not have to be
configured. Process variable, ANI0 (ANI1), is the controlled parameter, and control output, ANO0
(ANO1), is the regulator signal. When a closed contact is present on CCI0 (CCI1), remote setpoint
selection is possible using the R/L push button. While remote setpoint is selected, the control set-
point value is obtained from ANI2 (ANI3). Whenever an alarm condition associated with the control
loop occurs, the CCO0 (CCO1) contact is closed; otherwise, the contact is open.
FCS 53MC5000 Flexible Control Strategies
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