beautypg.com

G05 deviation/alarm calculation - 1 – Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller CUSTOMIZATION GUIDE User Manual

Page 35

background image

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

2-28