Parameter: Sum of extended PU times
•
Default setting (_:11341:103) Sum of extended PU times = 20 s
With the Sum of extended PU times parameter, you set the threshold value for the integrator. If the
integration reaches Sum of extended PU times, the stage operates if the pickup state is present.
This Sum of extended PU times represents one of the 4 selectivity criteria (pickup threshold, pickup
extension time, reset time, and integrator threshold value) for coordination of the relays on adjacent feeders.
It is comparable to the time grading of the overcurrent protection. The protection in the radial system which is
closest to the intermittent fault and picks up, has the shortest summation time Sum of extended PU
times.
Parameter: Reset time
•
Default setting (_:11341:104) Reset time = 300 s
With the parameter Reset time, you can define the maximum interval between 2 adjacent ground faults. If
the interval is larger than the Reset time, the counter and integrator are reset.
The Reset time parameter must be much higher than the operate value of the Sum of extended PU
times.
Parameter: Operate & flt.rec. blocked
•
Default setting (_:11341:2) Operate & flt.rec. blocked = no
You can block the operate indication, the fault recording, and the fault log with the Operate & flt.rec.
blocked parameter. In this case, a ground-fault log is created instead of the fault log.
EXAMPLE
[TiExaInt, 1, en_US]
Figure 6-113 Example of Selectivity Criteria of the Intermittent Ground-Fault Protection
Settings
Addr.
Parameter C Setting Options Default Setting
Stage 1
_:11341:1 Stage 1:Mode
•
off
•
on
•
test
off
_:11341:2 Stage 1:Operate &
flt.rec. blocked
•
no
•
yes
no
6.13.5
Protection and Automation Functions
6.13 Non-Directional Intermittent Ground-Fault Protection
SIPROTEC 5, Overcurrent Protection, Manual 549
C53000-G5040-C017-8, Edition 07.2017
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