Siemens SIPROTEC 5, Руководство пользователя

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With the
Min. active
parameter, you activate the level trigger in order to monitor the RMS value of the
current and to prevent it from dropping below the set values.
Parameter Value Description
yes
The RMS value of the current is monitored for undercurrent.
no
The RMS value of the current is not monitored for undercurrent.
If the
Min. trigger
does not operate phase-selectively, the set threshold value of the parameter
Min.
(Non-phs sel.)
applies to all phases.
If the
Min. trigger
operates phase-selectively, set the threshold values for the
Min. trigger
separately
for each phase. Then, the parameters
Min. phs A
,
Min. phs B
, and Min. phs C are effective.
The hysteresis is preset at the factory to 1.020 p.u. (equal to 2 %) of the parameter
Min. (Non-phs sel.)
and can be adjusted.
Parameter: +dM/dt dM/dt/+dM/dt hysteresis
•
Default setting
(_:9781:103) +dM/dt active
=
no
•
Default setting
(_:9781:107) +dM/dt (Non-phs sel.)
=
0.300 A
•
Default setting
(_:9781:124) +dM/dt phs A
=
0.300 A
•
Default setting
(_:9781:125) +dM/dt phs B
=
0.300 A
•
Default setting
(_:9781:126) +dM/dt phs C
=
0.300 A
•
Default setting
(_:9781:115) +dM/dt hysteresis
=
0.980 p.u.
•
Default setting
(_:9781:112) Filter time
=
2 periods
With the
+dM/dt active
parameter, you activate the gradient trigger in order to monitor the positive gradi-
ents of the RMS value of the current, using the set filtering time (input in periods).
Parameter Value Description
yes
The positive gradient of the RMS value of the current is monitored.
no
The positive gradient of the RMS value of the current is not monitored.
If the gradient trigger does not operate phase-selectively, the set threshold value of the parameter
+dM/dt
(Non-phs sel.)
applies to all phases.
If the gradient trigger operates phase-selectively, set the threshold values for the gradient trigger separately
for each phase. Then, the parameters
+dM/dt phs A
,
+dM/dt phs B
, and
+dM/dt phs C
are effective.
The hysteresis is preset at the factory to 0.980 p.u. (equal to 2 %) of the parameter
+dM/dt (Non-phs
sel.)
and can be adjusted.
Parameter: -dM/dt active/-dM/dt/-dM/dt hysteresis
•
Default setting
(_:9781:104) -dM/dt active
=
no
•
Default setting
(_:9781:108) -dM/dt (Non-phs sel.)
=
0.300 A
•
Default setting
(_:9781:127) -dM/dt phs A
=
0.300 A
•
Default setting
(_:9781:128) -dM/dt phs B
=
0.300 A
•
Default setting
(_:9781:129) -dM/dt phs C
=
0.300 A
•
Default setting
(_:9781:116) -dM/dt hysteresis
=
0.980 p.u.
•
Default setting
(_:9781:112) Filter time
=
2 periods
With the
-dM/dt active
parameter, you activate the gradient trigger in order to monitor the negative gradi-
ents of the RMS value of the current, using the set filtering time (input in periods).
Parameter Value Description
yes
The negative gradient of the RMS value of the current is monitored.
Fault Recorder
7.5 Trigger Functions 3-Phase
SIPROTEC 5, Fault Recorder, Manual 319
C53000-G5040-C018-5, Edition 11.2017