Zone Type Impedance Reach Z
Reverse Impedance
Reach Z’
Resistive Reach R
Reverse Resistive
Reach R’
3 Ph-Ph Offset Z3 Ph. Reach Z3’ Ph Rev Reach ½*R3 Ph. Resistive ½*R3’ Ph Res. Rev.
4 Ph-Ph Reverse Z4 Ph. Reach Z ½*R4 Ph. Resistive 0.25 R
P Ph-Ph Forward ZP Ph. Reach Z ½*RP Ph Resistive 0.25 R
P Ph-Ph Reverse ZP Ph. Reach Z ½*RP Ph Resistive 0.25 R
P Ph-Ph Offset ZQ Ph. Reach ZP’ Ph Rev Reach ½*RP Ph Resistive ½*RP’ Ph. Res. Rev.
Q Ph-Ph Forward ZQ Ph. Reach Z ½*RQ Ph Resistive 0.25 R
Q Ph-Ph Reverse ZQ Ph. Reach Z ½*RQ Ph Resistive 0.25 R
Q Ph-Ph Offset ZQ Ph. Reach ZQ’ Ph Rev Reach ½*RQ Ph Resistive ½*RQ’ Ph. Res. Rev.
Phase-to-earth Element Reaches
Zone Type Impedance Reach Z Reverse Impedance Reach Z’ Resistive Reach R
Reverse Resistive
Reach R’
1 Ph-Earth Forward
Z1 Gnd. Reach * (1 + k
ZN
)
0.25 Z R1 Gnd Resistive 0.25 R
2 Ph-Earth Forward
Z2 Gnd. Reach * (1 + k
ZN
)
0.25 Z R2 Gnd Resistive 0.25 R
3 Ph-Earth Forward
Z3 Gnd. Reach * (1 + k
ZN
)
0.25 Z R3 Gnd Resistive 0.25 R
3 Ph-Earth Reverse
Z3 Gnd. Reach * (1 + k
ZN
)
0.25 Z R3 Gnd Resistive 0.25 R
3 Ph-Earth Offset
Z3 Gnd. Reach * (1 + k
ZN
) Z3’ Gnd Rev Rch * (1 + k
ZN
)
R3 Gnd Resistive R3’ Ph Res. Rev
4 Ph-Earth Reverse
Z4 Gnd. Reach * (1 + k
ZN
)
Z R4 Gnd Resistive 0.25 R
P Ph-Earth Forward
ZP Gnd. Reach * (1 + k
ZN
)
0.25 Z RP Gnd Resistive 0.25 R
P Ph-Earth Reverse
ZP Gnd. Reach * (1 + k
ZN
)
0.25 Z RP Gnd Resistive 0.25 R
P Ph-Earth Offset
ZQ Gnd. Reach * (1 + k
ZN
) ZP’ Gnd Rev Rch * (1 + k
ZN
)
RP Gnd Resistive RP’ Gnd Res. Rev
Q Ph-Earth Forward
ZQ Gnd. Reach * (1 + k
ZN
)
0.25 Z RQ Gnd Resistive 0.25 R
Q Ph-Earth Reverse
ZQ Gnd. Reach * (1 + k
ZN
)
0.25 Z RQ Gnd Resistive 0.25 R
Q Ph-Earth Offset
ZQ Gnd. Reach * (1 + k
ZN
) ZQ’ Gnd Rev Rch * (1 + k
ZN
)
RQ Gnd Resistive RQ’ Gnd Res. Rev
where k
ZN
= (Z
0
- Z
1
) / 3Z
1
and is defined by two settings: kZN Res Comp and KZN Res Angle.
Note:
Not all products feature all zones.
Note:
With default settings applied, Directional Zones 1, 2, and 4 should appear Quadrilateral.
3.2.2
EARTH FAULT QUADRILATERAL CHARACTERISTICS
Quadrilateral characteristics are available for earth-fault protection. A mix of Directional Forward, Directional
Reverse, and Offset characteristics is available. Zone 1 and Zone 2 are Directional Forward. Zone 4 is Directional
Reverse. Other zones can be set independently as Offset, Directional Forward, or Directional Reverse. Each zone is
independent and is defined by an Impedance Reach line, a Reverse Impedance Reach Line, and two resistive
blinders. The two resistive blinders (Resistive Reach Line and Reverse Resistive Reach Line) are parallel to the zone
characteristic impedance angle.
The two reactance lines of each Phase-Earth Quadrilateral exhibit a characteristic tilt. The tilts of the Impedance
Reach Line and the Reverse Impedance Reach Line are independent. The tilt of both may be fixed. Alternatively,
Chapter 7 - Distance Protection P543i/P545i
154 P54x1i-TM-EN-1