Bender LINETRAXX VMD461, Руководство пользователя

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Menu
56 VMD461_D00314_01_M_XXEN/10.2018
Vector shift detection (78) (menu 3.5)
Vector shift detection is triggered by a sudden phase displacement (vector
shift).
A phase displacement may occur when a mechanical generator is used for
public grid infeed and the load is changing suddenly (as can be the case with
islanding).
In addition to the risk of islanding synchronisation to the rest of the system
can be lost during the interruption so that the generator and parts of the drive
may become electrically and mechanically overloaded during reconnection.
Function (menu 3.5.1) Enable/Disable vector shift detection and indicate
which phases should be monitored (L1 / L2 / L3 / all
/ off). If all phases are selected, the vector shift must
occur on all three phases simultaneously.
Otherwise the device will not trip.
If the device is set to single-phase connection
(3.1.2 System type: 1 AC) and vector shift detection
is enabled, L1 will always be automatically selected
as the phase to be monitored (independent of the
current parameter setting).
Resp. value (Menu 3.5.2) Specify a limit value at which tripping is to be
executed (in ° )
t
(start-up)
(menu 3.5.3) Time during which vector shift detection is
suppressed. This time begins as soon as the
VMD461 has connected the electrical installation.
t
(start-up)
has to ensure that there is no tripping due
to voltage fluctuations during the switch-on
period.
t
(on)
(menu 3.5.4 ) Switch-on delay after the vector shift detection has
resulted in a shutdown. You can choose between
a precise value and "off". In case of "off", the normal
switch-on delay from menu 3.8.3 is used.