setting polMethod. The polarizing quantity will be selected by the function in one of
the following three ways:
1. When polMethod = Voltage, VPol will be used as polarizing quantity.
2. When polMethod = Current, IPol will be used as polarizing quantity.
3. WhenpolMethod = Dual, VPol + IPol · ZNPol will be used as polarizing quantity.
The operating and polarizing quantity are then used inside the directional element, as
shown in figure
37, in order to determine the direction of the ground fault.
PUREV
0.6 * INDirPU
PUFW
-RCA -85 deg
40% of
INDirPU
INDirPU
RCA
65°
VPol = -3V
0
I = 3I
op 0
RCA +85 deg
RCA -85 deg
Characteristic
for PUREV
Characteristic
for PUFW
Characteristic for reverse
release of measuring steps
Characteristic for forward
release of measuring steps
-RCA +85 deg
ANSI11000243-1-en.ai
Operating area
Operating area
ANSI11000243 V1 EN
Figure 37: Operating characteristic for ground-fault directional element using the
zero sequence components
Section 7 1MRK 505 277-UUS C
Current protection
96
Technical Manual
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