en06000396_ansi.vsd
RFItFwdPG
X1
+XN
R
(Ohm/loop)
X
(ohm/loop)
RFItRevPG
RFItRevPG
RFItFwdPG
Kr·(
X1
+XN)
RFItRevPG
Kr·(
X1
+XN)
X1+
XN
RFItFwdPG
60 deg
60 deg
=
1
Kr
tan(60 deg)
ANSI06000396 V1 EN-US
Figure 83: Characteristic of FDPSPDIS (21) for phase-to-ground fault (setting parameters in
italic), ohm/loop domain (directional lines are drawn as "line-dot-dot-line")
Besides this, the 3I
0
residual current must fulfil the conditions according to equation
.
0
3 I
0.5
IMinPUPG
× ³
×
EQUATION2108-ANSI V1 EN-US
(Equation 48)
0
0
3
_
3
max
100
I Enable PG
I
Iph
×
³
×
EQUATION1812-ANSI V1 EN-US
(Equation 49)
where:
IMinPUPG
is the minimum operation current for forward zones
3I
0
Enable_PG is the setting for the minimum residual current needed to enable operation in the phase-to-ground
fault loops (in %).
Iphmax
is the maximum phase current in any of three phases.
7.2.6.2
Phase-to-phase fault
M13140-56 v3
For a phase-to-phase fault, the measured impedance by FDPSPDIS (21) will be according to
.
1MRK 502 066-UUS B
Section 7
Impedance protection
203
Technical manual
Summary of Contents for Relion 670 series
Page 1: ... RELION 670 SERIES Generator protection REG670 Version 2 1 ANSI Technical manual ...
Page 2: ......
Page 48: ...42 ...
Page 62: ...56 ...
Page 182: ...176 ...
Page 692: ...686 ...
Page 726: ...720 ...
Page 1014: ...1008 ...
Page 1242: ...1236 ...
Page 1362: ...1356 ...
Page 1386: ...1380 ...
Page 1422: ...1416 ...
Page 1431: ...1425 ...