CHAPTER 7: PROTECTION
PLUS
D90
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 166: Phase distance configuration window (example)
The following settings are available for each phase distance zone. There are five phase
distance zones of protection in each setting group.
Function
Range: Enabled, Disabled
Default: Enabled
This setting enables and disables the phase distance protection feature.
Direction
Range: Forward, Reverse, Non-Directional
Default: Forward
All phase distance zones are reversible. The forward direction is defined by the
setting, whereas the reverse direction is shifted 180° from that angle. The non-
directional zone spans between the forward reach impedance defined by the
settings, and the reverse reach impedance defined by
RCA
settings.
Reach RCA
Shape
Range: Mho, Quad
Default: Mho
This setting selects the shape of the phase distance function between the mho and
quadrilateral characteristics. The selection is available on a per-zone basis. The two
characteristics and their possible variations are shown in the following figures.
GROUPED PROTECTION ELEMENTS
RCA
Reach
and
Reverse Reach
Reverse
and
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