BECKWITH ELECTRIC M-4272, Инструкция

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M-4272 Instruction Book
4–44
The Delayed In-Phase Transfer Load Shedding
command is sent at the end of the Fast Transfer
time window if a fast transfer has
not been completed.
The purpose of this load shedding output is to
disconnect some loads so there will be a better
possibility of completing an In-Phase Transfer. There
may be a load that would cause the motor bus to
decay very quickly if a Fast Transfer was not
successful and it would be better to disconnect that
load so the rest of the motor bus would have a
better chance to complete an In-Phase transfer.
Another purpose could be to disconnect a very
sensitive load if a Fast Transfer is not possible.
When an output is selected it will be grayed out in
other output selection dialog boxes.
Common Settings/Load Shedding Outputs
The Load Shedding Outputs feature (Figure 4-38)
allows the user to select one or more outputs
(Figure 4-46) to indicate which output is to be used
for this Load Shedding.
The Load Shedding Function Selection also provides
the ability to select one of 5 choices to be used to
perform this load shedding feature. Typically Load
Shedding occurs after the Fast and In-Phase
Transfers have not been successful.
Figure 4-42 Transfer Completed Output
Selection Dialog Screen
Figure 4-43 Fast Transfer Load Shedding
Output Selection Dialog Screen
For the F27B
#
3, F81
#
1 or F81R
#
1 functions, when
the settings are satisfied the selected load shedding
output is closed. For Residual Voltage Transfer the
Load Shedding Output is closed when the motor
bus voltage drops below the Residual Voltage Limit.
The close command for Residual Voltage Transfer
is sent after the programmed load shedding time
delay. For the Fixed Time Transfer the Load Shedding
Output is closed when the Fixed Time Delay has
timed out. The close command for the Fixed Time
Delay Transfer is sent after the programmed load
shedding time delay.
When an output is selected it will be grayed out in
other output selection dialog boxes.
Common Settings/Incomplete Transfer Outputs
— The Incomplete Transfer Outputs feature (Figure
4-38) allows user to select one or more outputs
(Figure 4-45) to indicate which output is to be used
to indicate when a transfer has been incomplete.
Typically this output would be configured as a
latched output so it would remain closed like a
target to indicate that a transfer has been incomplete.
When an output is selected it will be grayed out in
the other output selection dialog.
Common Function Outputs Save/Cancel — The
Save selection (Figure 4-38) saves the Common
Function Settings Outputs Tab settings either to an
open file or to the target MBTS. Cancel, returns the
user to the previous open screen.