Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller FLEXIBLE CONTROL STRATEGIES - Manual (Page 58)

2.7.36 CONTROL 3
The Control 3 (CON 3) module combines the operations of Deviation/Alarm Calculation (D/C) and
Proportional Integral Derivative (PID) modules. The D/C functionality of the CON 3 module calcu-
lates the deviation (DV) value from the setpoint (SP) and the process variable (PV). Before the cal-
culation is performed, the setpoint value is conditioned not to exceed the T1 rate of change limit. If
the calculated deviation falls within the Control Zone (CZ) value, the deviation is forced to 0.0. If
the DV value exceeds parameter values that were entered for alarm limits PL1 and PL2, and the
Alarm Deadband (ADB), then Process Alarms PA1 and PA2 are activated as determined by the
Control Alarm Mode (AIX) parameter selection. The DV output from the D/C functionality is routed
internally as the DV input to the PID functionality, which means it can not be accessed as a wirelist
datapoint as would be the case if both modules were separate. The PID functionality computes the
Control Output (CO) signal based on the DV input from the D/C, other input variables, and parame-
ter entries (see Section 2.7.15 or 2.7.26 for PID formulas).
When the Auto/Manual Switch 3 (AMS 3) module is in auto mode, the CON 3 CO output is forced
to equal the Auto Value (CO) out from the AMS 3 module.
The tables that follow list the input variables and the parameters. An illustration of the Control 3
module follows the tables.
Inputs
WIRELIST SYMBOL DATA
TYPE
ASSIGNED VALUE
B230 PV3 C
B231 SP3 C
B232 FF3 C
Output Datapoints: C227, C229, C231, L182, L183
Parameters Parameters
SYMBOL DATAPOINT ASSIGNED VALUE SYMBOL DATAPOINT ASSIGNED VALUE
T1-3 C225 OL3 C218
CZ3 C222 IR3 C223
PL1-3 C211 PB3 C214
PL2-3 C212 TR3 C215
ADB3 C213 TD3 C216
AIX3 B350 MR3 C219
OH3 C217 RSW3 L178
Section 2. FCS Modules
CON-3
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