ABB RELION Series Technical Manual page 350

Section 4
Protection functions
344
boundary line counterclockwise from the vertical axis. A positive Susceptance tilt
Ang value rotates the oversusceptance boundary line counterclockwise from the
horizontal axis.
In case of the non-directional conductance and susceptance criteria, the Conductance
reverse setting must be set to a smaller value than Conductance forward and the
Susceptance reverse setting must be set to a smaller value than Susceptance forward.
Operation is achieved when the measured admittance moves outside the
characteristic.
The combined overconductance and oversusceptance criterion is applicable in high-
resistance earthed, unearthed and compensated networks or in the systems where the
system earthing may temporarily change during normal operation from compensated
to unearthed system.
GUID-1A21391B-A053-432B-8A44-7D2BF714C52D V2 EN
Figure 177: Combined forward directional overconductance and forward
directional oversusceptance characteristic. Left figure: the
Conductance tilt Ang and Susceptance tilt Ang settings equal zero
degrees. Right figure: the setting Conductance tilt Ang > 0 degrees
and the setting Susceptance tilt Ang < 0 degrees.
1MRS758755 A
REC615 and RER615
Technical Manual