198
D90
PLUS
LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED PROTECTION ELEMENTS
CHAPTER 7: PROTECTION
Figure 174: Ground distance settings configuration
The following settings are available for each ground distance zone. There are five ground
distance zones of protection in each setting group.
Function
Range: Enabled, Disabled
Default: Disabled
This setting enables and disables the phase distance protection feature.
Direction
Range: Forward, Reverse, Non-directional
Default: Forward
All ground distance zones are reversible. The forward direction is defined by the
RCA
setting and the reverse direction is shifted by 180° from that angle. The non-directional
zone spans between the forward reach impedance defined by the
Reach
and
RCA
settings, and the reverse reach impedance defined by the
Reverse Reach
and
Reverse
Reach RCA
settings.
Shape
Range: Mho, Quad
Default: Mho
This setting selects the shape of the ground distance characteristic between the mho
and quadrilateral characteristics. The selection is available on a per-zone basis.
The directional and non-directional mho and quadrilateral ground distance
characteristics are shown below.