CHAPTER 4: SETPOINTS
PROTECTION
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL
4–219
Phase Reversal (47)
The 889 can detect the phase rotation of the three phase voltages. When all three Phase-
to-Phase Voltages (V
ab
, V
bc
and V
ca
) are greater than 50% of VT, if the phase rotation of the
three phase voltages is not the same as the Phase Rotation setpoint (programmed under
Setpoints/System/Power System), and there is no fuse failure, either an alarm or a trip will
occur within the programmed Pickup Delay time.
NOTE
NOTE:
VT is the secondary voltage programmed under Setpoints > System > Voltage Sensing >
Phase VT Secondary.
Path:
Setpoints > Protection > Group 1(6) > Voltage > Phase Reversal
FUNCTION
Range: Disabled, Trip, Alarm, Latched Alarm, Configurable
Default: Disabled
This setting enables the Phase Reversal functionality.
PICKUP DELAY
Range: 0.00 to 180.00 s in steps of 0.01 s
Default: 1.00 s
This setting specifies the pickup delay of the element.
DROPOUT DELAY
Range: 0.00 to 180.00 s in steps of 0.01 s
Default: 1.00 s
This setting defines the reset delay of the element.
BLOCK
Range: FlexLogic Operand
Default: Off
The Phase Reversal can be blocked by any asserted FlexLogic operand.
OUTPUT RELAY X
For details see
EVENTS
Range: Enabled, Disabled
Default: Enabled
TARGETS
Range: Self-Reset, Latched, Disabled
Default: Self-Reset