Allen-Bradley LOGIX 5000 Reference Manual page 194

Chapter 1 Process Control Instructions
194
CVROCNegAlarm REAL
SP REAL
SPPercent REAL
SPHAlarm BOOL
SPLAlarm BOOL
PVPercent REAL
E REAL
EPercent REAL
InitPrimary BOOL
WindupHOut BOOL
WindupLOut BOOL
Ratio REAL
RatioHAlarm BOOL
RatioLAlarm BOOL
ProgOper BOOL
CasRat BOOL
Auto BOOL
Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
CV rate of change alarm indicator. TRUE
when the calculated rate of change for CV
exceeds CVROCNegLimit.
Current setpoint value. The value of SP is
used to control CV when in the Auto, the
CascadeRatio, or the PV Tracking mode,
scaled in PV units.
The value of SP expressed in percent of
span of PV.
SPPercent = ((SP − PVEUMin ) * 100) /
PVSpan
where
PVSpan = PVEUMax − PVEUMin
SP high alarm indicator. TRUE when the SP
≥ SPHLimit.
SP low alarm indicator. TRUE when the SP
≤ SPLLimit.
PV expressed in percent of span.
PVPercent = (( PV − PVEUMin ) * 100) /
PVSpan
PV Span calculation: PVSpan =
( PVEUMax − PVEUMin )
Process error. Difference between SP and
PV, scaled in PV units.
The error expressed as a percent of span.
Initialize primary loop command. TRUE
when not in CasRat mode or when
CVInitializing is TRUE. This signal normally
would be used by the CVInitReq input of a
primary loop.
Windup high indicator. TRUE when either a
SP high or CV high/low limit has been
reached. This signal will typically be used
by the WindupHIn input to limit the
windup of the CV output on a primary loop.
Windup low indicator. TRUE when either a
SP or CV high/low limit has been reached.
This signal will typically be used by the
WindupLIn input to limit the windup of the
CV output on a primary loop.
Current ratio multiplier, no units.
Ratio high alarm indicator. TRUE when
Ratio > RatioHLimit.
Ratio low alarm indicator. TRUE when Ratio
< RatioLLimit.
Program/Operator control indicator. TRUE
when in Program control. FALSE when in
Operator control.
CascadeRatio mode indicator. TRUE when
in the CascadeRatio mode.
Auto mode indicator. TRUE when in the
Auto mode.