ABB Relion 670 series - Phase-to-phase fault

03 I 0.5 IMinPUPG× ³ ×
EQUATION2108-ANSI V1 EN (Equation 27)
0
0
3 _
3 max
100
I Enable PG
I Iph× ³ ×
EQUATION1812-ANSI V1 EN (Equation 28)
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.
6.3.3.2 Phase-to-phase fault
For a phase-to-phase fault, the measured impedance by FDPSPDIS (21) will be
according to equation 29.
2
Vm Vn
ZPHS
In
-
=
- ×
EQUATION1813-ANSI V1 EN (Equation 29)
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.
1MRK505222-UUS C Section 6
Impedance protection
223
Technical reference manual