ABB RED615 Technical Manual page 332

Section 4
Protection functions
326
Im(Yo)
OPERATE OPERATE
Conductance reverse
Re(Yo)
Conductance forward
OPERATE OPERATE
GUID-F5487D41-6B8E-4A7A-ABD3-EBF7254ADC4C V1 EN
Figure 163: Non-directional overconductance characteristic. Left figure:
classical non-directional overconductance criterion. Middle figure:
characteristic is tilted with negative tilt angle. Right figure:
characteristic is tilted with positive tilt angle.
Forward directional overconductance characteristic
The forward directional overconductance criterion is enabled with the Operation
mode setting set to "Go" and Directional mode set to "Forward". The characteristic
is defined by one overconductance boundary line with the Conductance forward
setting. For the sake of application flexibility, the boundary line can be tilted with
the angle defined with the Conductance tilt Ang setting. By default, the tilt angle is
zero degrees, that is, the boundary line is a vertical line in the admittance plane. A
positive tilt value rotates the boundary line counterclockwise from the vertical axis.
Operation is achieved when the measured admittance moves over the boundary line.
The forward directional overconductance criterion is applicable in
high-resistance earthed and compensated networks. It must not be
applied in unearthed networks.
Im(Yo)
OPERATE
Re(Yo)
Conductance forward
OPERATE
GUID-43F312AA-874A-4CE7-ABFE-D76BA70B7A5D V1 EN
Figure 164: Forward directional overconductance characteristic. Left figure:
classical forward directional overconductance criterion. Middle
figure: characteristic is tilted with negative tilt angle. Right figure:
characteristic is tilted with positive tilt angle.
Im(Yo)
Conductance tilt Ang <0
OPERATE OPERATE
Conductance reverse
Re(Yo)
Conductance forward
OPERATE OPERATE
Im(Yo)
Conductance tilt Ang <0
OPERATE
Re(Yo)
Conductance forward
OPERATE
1YHT530004D05 D
Im(Yo)
Conductance tilt Ang >0
OPERATE OPERATE
Conductance reverse
Re(Yo)
Conductance forward
OPERATE OPERATE
Im(Yo)
Conductance tilt Ang >0
OPERATE
Re(Yo)
Conductance forward
OPERATE
615 series
Technical Manual