Siemens SITRANS PCS 7, Руководство по эксплуатации функций

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You can define a hysteresis (
L1/2/3_Hyst
) and a response time (
L1/2/3_RespT
) for the
limits, for example to suppress signal flatter. You can also modify the limits, the hysteresis and
the response time via the faceplate.
Gradient monitoring
The gradient
PV_Grad0
is calculated by means of a delay function configurable
using
LagTime
. During calculation of the gradient, jumps in the input value
PV_In
are
smoothed.
The peak values of the gradient are output in the output parameters
PV_GradNP0
(negative
gradient) and
PV_GradPP0
(positive gradient). These are reset when the operator enters the
corresponding command for resetting.
The slope of the gradient
PV_Grad
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 HART via
PDM and read by an operator action in the "Parameters" faceplate view with "Read
configuration" or configured by the user himself if SITRANS P communication does not exist.
SITRANS P
10.1 SitransP
SITRANS Library for PCS 7
Function Manual, 05/2019, A5E35351976-11
369