R1 zone x
X
R
X1 zone x
Forward
-R1 zone x
X
R
-X1 zone x
Reverse
X
R
-X1 reverse zone x
Non-directional
X1 zone x
R1 zone x
α
α
Figure 542: Settings which define the line reach for phase-to-phase or three-phase
impedance measuring elements if Impedance mode Zn = "Rectangular"
In case of phase-to-earth impedance measuring elements, the line reach is defined
with:
• Resistive reach : (2⋅
R1 zone x + R0 zone x)/3, (x = 1...5)
• Reactive reach : (2⋅
X1 zone x + X0 zone x)/3, (x = 1...5)
X
R
(2
⋅
X1 zone x + X0 zone x)/3
Forward
X
R
Reverse
(2
⋅
R
1
zo
n
e
x
+
R
0
zo
ne
x
)/3
-(2
⋅
X1 zone x + X0 zone x)/3
-(
2
⋅
R
1
zo
n
e
x
+
R
0
zo
n
e
x
)/3
Figure 543: Settings which define the line reach for phase-to-earth impedance
measuring elements if Impedance mode Zn = "Rectangular", forward or reverse
directionality
In case of non-directional characteristics, the reactive reach in reverse direction is
defined with the
X1 reverse zone x (x = 1...5) setting. The total reactive reach in
reverse direction includes a part which is common to both forward and reverse
direction. This part is automatically calculated based on the values of the settings
R1 zone x, R0 zone 0, X1 zone x and X0 zone x. The characteristic line angle, denoted
as α, is the same for forward and reverse direction.
Protection functions
1MRS759142 F
970
REX640
Technical Manual