GE D90 Plus Instruction Manual page 268

GROUPED PROTECTION ELEMENTS
258
Source
Range: LINE (SRC 1), BKR 1 (SRC 2), BKR 2 (SRC 3)
Default: LINE (SRC 1)
This setting selects the signal source for the negative-sequence time overcurrent
protection element.
Pickup
Range: 0.000 to 30.000 pu in steps of 0.001
Default: 1.000 pu
This setting specifies the neutral time overcurrent pickup level in per-unit values.
Curve
Range: IEEE Mod Inv, IEEE Very Inv, IEEE Ext Inv, IEC Curve A, IEC Curve B, IEC Curve C, IEC
Short Inv, IAC Ext Inv, IAC Very Inv, IAC Inverse, IAC Short Inv, I2t, Definite Time, FlexCurve A,
FlexCurve B, FlexCurve C, FlexCurve D
Default: IEEE Mod Inv
This setting selects the inverse time overcurrent curve style.
TD Multiplier
Range: 0.00 to 600.00 in steps of 0.01
Default: 1.00
This setting specifies a multiple of the base curve shape specified by the
Programming this value to zero results in an instantaneous response to all current levels
above pickup.
Reset
Range: Instantaneous, Timed
Default: Instantaneous
The "Instantaneous" reset method is intended for applications with other relays, such as
most static relays, which set the energy capacity directly to zero when the current falls
below the reset threshold. The "Timed" reset method can be used where the relay must
coordinate with electromechanical relays.
Block
Range: any FlexLogic operand or shared operand
Default: Off
Assertion of the operand assigned to this setting blocks operation of the negative-
sequence time overcurrent element.
Events
Range: Enabled, Disabled
Plus
Default: varies with UR
This setting enables and disables the logging of negative-sequence time overcurrent
events in the sequence of events recorder.
The figure shows the logic for the negative-sequence time overcurrent 1 element. The logic
is identical for all negative-sequence time overcurrent elements.
-series model; see the EnerVista UR
PLUS
D90 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 7: PROTECTION
setting.
Curve
Plus
Setup software