Definite Time Directional High-Set Elements 67-2, 67N-2, 67-3, 67N-3 - Siemens SIPROTEC 4 Manual

Functions
2.3 Directional Overcurrent Protection 67, 67N
Directional Time
Overcurrent Protec-
tion Elements
67N-3
67N-TOC

Definite Time Directional High-set Elements 67-2, 67N-2, 67-3, 67N-3

2.3.2
For each element an individual pickup value 67-2 PICKUP, 67-3 PICKUP or 67N-2 PICKUP, 67N-3
PICKUP is set which can be measured as Fundamental or True RMS. Each phase current and the ground
current is compared with the common pickup value for each element 67-2 PICKUP, 67-3 PICKUP or
67N-2 PICKUP, 67N-3 PICKUP, and it is signaled when the value is exceeded provided that the fault direc-
tion is the same as the parameterized direction. After the associated delay times 67-2 DELAY, 67-3 DELAY
or 67N-2 DELAY, 67N-3 DELAY have expired, the tripping commands are initiated which are equally avail-
able separately for each element. The dropout value is approximately 95% of the pickup value for currents >
0.3 Ι .
Nom
Pickup can be stabilized by setting dropout times 1518 67 T DROP-OUT or 1618 67N T DROP-OUT. This
time is started and maintains the pickup condition if the current falls below the threshold. Therefore, the func-
tion does not drop out instantaneously. The trip delay times 50-2 DELAY, 67-3 DELAY or 50N-2 DELAY,
67N-3 DELAY continue during that time. After the dropout delay time has elapsed, the pickup is reported
OFF and the trip delay time is reset unless the threshold 50-2 PICKUP, 67-3 PICKUP or 50N-2 PICKUP,
67N-3 PICKUP has been exceeded again. If the threshold is exceeded again during the dropout delay time,
the time is canceled. The trip delay time 50-2 DELAY, 67-3 DELAY or 50N-2 DELAY, 67N-3 DELAY
continues. If the threshold value is exceeded after this time has elapsed, the trip command is issued immedi-
ately. If the threshold value is not exceeded at this time, there is no reaction. If the threshold value is
exceeded again after expiry of the trip command delay time, while the dropout delay time is still running, trip-
ping is initiated immediately.
Each of these elements can be directional or non-directional (non-directional from V4.7 on).
These elements can be blocked by the automatic reclosing function (79 AR).
The following figure gives an example of the logic diagram for the high-set elements 67-2 of the phase
currents. The high-set element 67-3 is structured identically.
84
Connection to Auto-
matic Reclosing
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Manual CLOSE Dynamic Cold
Load Pickup
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E50417-G1140-C343-A8, Edition 12.2017
Inrush Restraint
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SIPROTEC 4, 7SJ80, Manual