GE 845 Instruction Manual page 401

CHAPTER 4: SETPOINTS
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845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
and the selected Trip seal-in time expires. This setpoint provides flexibility to operate the
Trip output relay by selecting an operand from the list of FlexLogic operands, contact
inputs, virtual inputs, or remote inputs. For example the operand "Trip Bus 1 Op" can be
selected to activate this output according to the trip conditions configured under the
Trip Bus 1 menu.
REMOTE OPEN BKR2
Range: Any FlexLogic operand
Default: Off
REMOTE OPEN BKR3
Range: Any FlexLogic operand
Default: Off
REMOTE CLOSE BKR1
Range: Any FlexLogic operand
Default: Off
The setting specifies the input which when asserted initiates a Close command to the
output relay selected to close Breaker 1. This setpoint provides the flexibility to operate
the output relay by selecting an operand from the list of FlexLogic operands, contact
inputs, virtual inputs, or remote inputs.
REMOTE CLOSE BKR2
Range: Any FlexLogic operand
Default: Off
REMOTE CLOSE BKR3
Range: Any FlexLogic operand
Default: Off
The 845 relay allows local or remote breaker control to be performed even if no breaker
contact (52a or 52b) has been configured on the relay to detect the status of the breakers.
To avoid controlling the breakers when their status is unknown, it is strongly
recommended, that at least one contact, i.e. breaker 52a, or 52b is connected to the relay
for each breaker status detection.
EVENTS
Range: Disabled, Enabled
Default: Enabled
TARGETS
Range: Disabled, Self-reset, Latched
Default: Self-reset
In Self-reset mode, the targets remain active until the function drops out. In Latched
mode, the target is set until deactivated by a Reset command.
Breaker Selection
The front panel provides three pushbuttons to be used for local breaker control:
Pushbutton F1 is used for breaker selection, and PB1 and PB2, for breaker open, and
breaker close commands respectively.
By default the relay is in "Remote Mode", and the pushbuttons are inactive for breaker
control. The pushbuttons become active only when the relay is set in "Local Mode" (the LED
"Local Mode" is lit).
The selection of the breakers is performed using the transformer Single Line Diagram
screen (SLD) from below.
Depending on the 845 relay order code, the following SLD screens will be available for
selection:
1. 845 relay for a two winding transformer without voltage (2-NN order code option)
CONTROL
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