ABB RELION 670 Series Technical Manual page 267

1MRK 502 066-UUS B
RFPG
ANSI05000661 V3 EN-US
Figure 123: Characteristic for phase-to-ground measuring , ohm/loop domain
Technical manual
X (Ohm/loop)
RFPG R1+Rn RFPG
X1+Xn
j
n
RFPG RFPG
X1+Xn
R1+Rn RFPG
X0-X1
=
Xn
3
R0-R1
=
Rn
3
j
n
R
(Ohm/loop)
ANSI05000661-3-en.vsd
Section 7
Impedance protection
261