268
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED PROTECTION ELEMENTS
CHAPTER 7: PROTECTION
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 neutral overvoltage protection element.
Pickup
Range: 0.000 to 1.250 pu in steps of 0.001
Default: 0.300 pu
This setting specifies the neutral overvoltage pickup level in per-unit values.
Curve
Range: Definite Time, FlexCurve A, FlexCurve B, FlexCurve C
Default: Definite Time
This setting selects whether the neutral overvoltage element provides a time-delayed
operating characteristic versus the applied voltage (FlexCurves™ A, B, or C) or is used as
a definite time element.
Pickup Delay
Range: 0.00 to 600.00 seconds in steps of 0.01
Default: 1.00 seconds
This setting specifies the minimum operating time of the neutral overvoltage element.
This setting applies only if the
Curve
setting is “Definite Time”.
Reset Delay
Range: 0.00 to 600.00 seconds in steps of 0.01
Default: 1.00 seconds
This setting specifies the minimum reset time of the neutral overvoltage element.
Block
Range: any FlexLogic™ operand or shared operand
Default: Off
Assertion of the operand assigned to this setting blocks the neutral overvoltage
element.
Events
Range: Enabled, Disabled
Default: Disabled
This setting enables and disables the logging of neutral overvoltage events in the
sequence of events recorder.
The logic for the neutral overvoltage 1 element is shown below. The logic is similar for all
neutral overvoltage elements.
Figure 229: Neutral overvoltage scheme logic
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