G05 deviation/alarm calculation - 1 – Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller CUSTOMIZATION GUIDE User Manual
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G05
DEVIATION/ALARM CALCULATION - 1
INPUTS
NAME
SYMBOL
DATAPOINT
SETPOINT
SP1
C137
PROCESS VARIABLE
PV1
C136
PARAMETERS
SETPOINT SLEW RATE
T11
C153
CONTROL ZONE
CZ1
C150
ALARM INDEX
AIX1
B340
ALARM LIMIT 1
PL11
C139
ALARM LIMIT 2
PL21
C140
ALARM DEADBAND
ADB1
C141
OUTPUTS
DEVIATION
DV1
C157
ALARM A
PA11
L134
ALARM B
PA21
L135
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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