Phase-To-Phase Fault - ABB Relion 670 Series Technical Reference Manual

1MRK505222-UUS C
6.3.3.2
Technical reference manual
× ³ ×
3 I 0.5 IMinPUPG
0
EQUATION2108-ANSI V1 EN
3 I Enable PG _
× ³ ×
3 I 0 Iph
0
100
EQUATION1812-ANSI V1 EN
where:
IMinPUPG
is the minimum operation current for forward zones
3I Enable_PG is the setting for the minimum residual current needed to enable operation in the phase-to-
0
ground fault loops (in %).
Iphmax is the maximum phase current in any of three phases.

Phase-to-phase fault

For a phase-to-phase fault, the measured impedance by FDPSPDIS (21) will be
according to equation 29.
-
Vm Vn
=
ZPHS
- ×
2 In
EQUATION1813-ANSI V1 EN
Vm is the leading phase voltage, Vn the lagging phase voltage and In the phase current
in the lagging phase n.
The operation characteristic is shown in figure 103.
max
Section 6
Impedance protection
(Equation 27)
(Equation 28)
(Equation 29)
223