Siemens SIPROTEC 4 7VK61, Руководство пользователя

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[ls-versag-zeitabl-2stuf-versag-oz-020802, 1, en_GB]
Figure 2-47 Time sequence example for normal clearance of a fault, and with circuit breaker failure, using
two-stage breaker failure protection
Single-stage circuit breaker failure protection
With single-stage operation, the adjacent circuit breakers (i.e. the circuit breakers of the busbar zone and, if
applicable, the circuit breaker at the remote end) are tripped after a delay time
T2
(address 3906) should the
fault not have been cleared within this time.
The times
T1-1pole
(address 3904) and
T1-3pole
(address 3905) are then set to ∞ since they are not
needed.
You can also use the first stage alone if you wish to use different delay times after 1-pole and 3-pole tripping
of the feeder protection. In this case set
T1-1pole
(address 3904) and
T1-3pole
(address 3905) separately,
but address 3903
1p-RETRIP (T1)
to
NO
, to avoid a 1-pole trip command to the busbar. Set
T2
(address3906) to ∞ or equal to
T1-3pole
(address 3905). Be sure that the correct trip commands are
assigned to the desired trip relay(s).
The delay time is determined from the maximum operating time of the feeder circuit breaker, the reset time of
the current detectors of the circuit breaker failure protection, plus a safety margin which allows for any toler-
ance of the delay timers.
Figure 2-48 illustrates the timing of a typical circuit breaker failure scenario The
dropout time for sinusoidal currents is ≤ 15 ms. If current transformer saturation is anticipated, the time
should be set to 25 ms.
[ls-versag-zeitabl-1stuf-versag-oz-020802, 1, en_GB]
Figure 2-48 Time sequence example for normal clearance of a fault, and with circuit breaker failure, using
single-stage breaker failure protection
Functions
2.6 Circuit breaker failure protection (optional)
SIPROTEC 4, 7VK61, Manual 127
C53000-G1176-C159-5, Edition 05.2018