ANSI05000670-2-en.vsd
X1
R
X
0.5·RFltFwdPP
Kr·X1
Kr·X1
X1
60 deg
60 deg
0.5·RFltFwdPP
0.5·RFltRevPP
0.5·
RFltRevPP
0.5·RFltRevPP
1
Kr
tan(60 deg)
=
0.5·RFltFwdPP
)/(
phaseW
)/( phaseW
ANSI05000670 V2 EN
Figure 103: The operation characteristics for FDPSPDIS (21) at phase-to-phase
fault (setting parameters in italic, directional lines drawn as "line-dot-dot-
line"), ohm/phase domain
In the same way as the condition for phase-to-ground fault, there are current conditions
that have to be fulfilled in order to release the phase-to-phase loop. Those are
according to equation 30 or equation 31.
EQUATION2109-ANSI V1 EN (Equation 30)
0 max
100
3
INBlockPP
IphI < ×
EQUATION2110-ANSI V1 EN (Equation 31)
where:
IMinPUPG
is the minimum operation current for ground measuring loops,
3I0BLK_PP
is 3I
0
limit for blocking phase-to-phase measuring loop and
Iphmax is maximal magnitude of the phase currents.
Section 6 1MRK505222-UUS C
Impedance protection
224
Technical reference manual
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