G06 deviation/alarm calculation - 2 – Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller CUSTOMIZATION GUIDE User Manual
Page 36

G06
DEVIATION/ALARM CALCULATION - 2
INPUTS
NAME
SYMBOL
DATAPOINT
SETPOINT
SP2
C173
PROCESS VARIABLE
PV2
C172
PARAMETERS
SETPOINT SLEW RATE
T12
C189
CONTROL ZONE
CZ2
C186
ALARM INDEX
AIX2
B345
ALARM LIMIT 1
PL12
C175
ALARM LIMIT 2
PL22
C176
ALARM DEADBAND
ADB2
C177
OUTPUTS
DEVIATION
DV2
C193
ALARM A
PA12
L158
ALARM B
PA22
L159
Description:
This subroutine calculates and loads the deviation value based on setpoint (SP) and
process variable (PV). Before the calculation is performed the setpoint value is
conditioned so as not to exceed the rate of change limit specified by T1. If the
calculated deviation falls within the CZ value, then deviation is forced to 0.0. This
module also determines if alarm conditions exist based on AIX, PL1, PL2 and ADB.
Results of the alarm tests are loaded to PA1 and PA2. Refer to Section 4.1.6 of
Instruction Bulletin 53MC5000 for an explanation of AIX values.
MODULAR CONTROLLER CUSTOMIZATION GUIDE
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