ABB Relion 670 series - Phase-To-Phase Fault

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 48 and
equation
49.
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
equation
50.
1MRK 502 066-UUS B Section 7
Impedance protection
203
Technical manual