Siemens SITRANS PCS 7, Function Manual

Page: 783 / 850

The slope of the gradient
PV_Grad0
can be monitored for the following limits:
● Limit (high) for the positive gradient (
GradHUpLim
)
● Limit (high) for the negative gradient (
GradHDnLim
)
● Limit (low) for the absolute gradient (
GradLLim
)
Activation of the individual monitoring functions is carried out at the corresponding "Enable"
parameters, e.g.
GradHUpEn
for activating the high gradient limit for positive gradients
(
GradHUpLim
).
Reaching or violation of your defined limits is indicated at the corresponding "Active" output
parameters, e.g. by means of
GradHUpAct
= 1 for the limit (high) for the positive gradient.
Messages can be output for these alarms. You can activate these as follows:
● Message for alarms (high) for the positive gradient:
GradHUpMsgEn
= 1
● Message for alarms (high) for the negative gradient:
GradHDnMsgEn
= 1
● Message for alarms (low) for the absolute gradient:
GradLMsgEn
= 1
Suppressing messages using the
MsgLock
parameter
This block provides the standard "Suppressing messages using the
MsgLock
parameter"
function that is described in the APL Online Help.
Bypass function
This block provides the standard function Interlocking functions (Page 13).
Selecting a unit of measure
This block provides the standard function Selecting a unit of measure (Page 13). The units for
the 4 to 20 mA signal and the HART variables are configured on the device of the Sitrans LU
via PDM and read by an operator action in the "Parameters" faceplate view with "Read
configuration" or configured by the user himself if HART communication does not exist.
Forming the signal status for blocks
This block provides the standard "Form and output signal status for technological blocks"
function that is described in the APL Online Help.
The worst signal status
ST_Worst
for the block is formed from the process values:
●
PV_In.ST
●
PV.ST
●
SV.ST
Release for maintenance
This block provides the standard "Maintenance enable" function that is described in the APL
Online Help.
SITRANS LU HART
17.1 SitrLuHA
SITRANS Library for PCS 7
Function Manual, 05/2019, A5E35351976-11
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