ABB RELION RET670, Applications Manual

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1 2
A B
EnergizingCheck
Line voltage Bus voltage
ANSI10000078-4-en.vsd
VLiveBusEnerg > 50 - 120 % of GblBaseSelBus
VLiveLineEnerg > 50 - 120 % of GblBaseSelLine
VDeadBusEnerg < 10 - 80 % of GblBaseSelBus
VDeadLineEnerg < 10 - 80 % of GblBaseSelLine
VMaxEnerg < 50 - 180 % of GblBaseSelBus and/or
GblBaseSelLine
ANSI10000078 V4 EN-US
Figure 306: Principle for the energizing check function
The energizing operation can operate in the dead line live bus (DLLB) direction, dead
bus live line (DBLL) direction, or in both directions over the circuit breaker.
Energizing from different directions can be different for automatic reclosing and
manual closing of the circuit breaker. For manual closing it is also possible to allow
closing when both sides of the breaker are dead, Dead Bus Dead Line (DBDL).
The equipment is considered energized (Live) if the voltage is above the set value for
VLiveBusEnerg or VLiveLineEnerg of the base voltages GblBaseSelBus and
VGblBaseSelLine , which are defined in the Global Base Value groups, according to the
setting of GblBaseSelBus and GblBaseSelLine ; in a similar way, the equipment is
considered non-energized (Dead) if the voltage is below the set value for
VDeadBusEnerg or VDeadLineEnerg of the respective Global Base Value groups. A
disconnected line can have a considerable potential due to factors such as induction
from a line running in parallel, or feeding via extinguishing capacitors in the circuit
breakers. This voltage can be as high as 50% or more of the base voltage of the line.
Normally, for breakers with single breaking elements (<330 kV) the level is well below
30%.
When the energizing direction corresponds to the settings, the situation has to remain
constant for a certain period of time before the close signal is permitted. The purpose
of the delayed operate time is to ensure that the dead side remains de-energized and
that the condition is not due to temporary interference.
15.1.2.4 Voltage selection
M12321-3 v11
The voltage selection function is used for the connection of appropriate voltages to the
synchronism check, synchronizing and energizing check functions. For example, when
the IED is used in a double bus arrangement, the voltage that should be selected
Section 15
1MRK 504 163-UUS A
Control
682 Transformer protection RET670 2.2 ANSI
Application manual