ABB RELION REX640 Technical Manual page 898

Section 4
Protection functions
892
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.
-X1 reverse zone x
⋅
* (2 X1 zone x + X0 zone x)/3
X1 zone x
GUID-FE065A8A-A0CA-4695-9ABE-D1E83027E0E0 V1 EN
Figure 485: Settings which define the line reach for phase-to-earth impedance
measuring elements if Impedance mode Zn = "Rectangular", non-
directional directionality
Impedance mode Zn = Polar
In case of phase-to-phase or three-phase impedance measuring elements, the line
reach is defined with:
• Z1 zone x (x = 1...5)
• Z1 angle zone x (x = 1...5)
In case of non-directional characteristics, the reactive reach magnitude in reverse
direction is defined with the Z1 reverse zone x (x = 1...5) setting. The characteristic
line angle, Z1 angle zone x, is the same for forward and reverse direction.
Non-directional
X
⋅
(2 X1 zone x + X0 zone x)/3
α
-X1 reverse zone x
* (2 ⋅ R1 zone x + R0 zone x)/3
X1 zone x
1MRS759142 C
α
R
⋅
(2 R1 zone x + R0 zone x)/3
REX640
Technical Manual