ABB 615 Series - Page 394

Re(Yo)
Im(Y o)
Conductanceforward
Conductancereverse
ConductancetiltAng<0
Re(Yo)
Im(Y o)
ConductancetiltAng>0
Re(Yo)
Im(Yo)
TRIPTRIP
TRIP TRIP
TRIPTRIP
TRIP TRIP
TRIPTRIP
TRIP TRIP
Conductanceforward
Conductancereverse
Conductanceforward
Conductancereverse
GUID-87294480-9029-4D2C-AAAE-358147FA262E V1 EN
Figure 182: 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 grounded and compensated networks. It must not be applied in
ungrounded networks.
Section 4 1MAC059074-MB A
Protection functions
388 615 series ANSI
Technical Manual