3I0Enable_PG
This setting opens up an opportunity to enable phase-to-ground measurement for phase-
to-phase-ground faults. It determines the level of residual current (3I0) above which
phase-to-ground measurement is activated (and phase-to-phase measurement is blocked).
The relations are defined by equation
334.
0 max
3I0Enable _ PG
3
100
ph
I
I I× ³ ×
EQUATION2548-ANSI V1 EN (Equation 334)
Where:
3I0Enable_PG
the setting for the minimum residual current needed to enable operation in the phase-to-
ground fault loops in %
I
phmax
the maximum phase current in any of the three phases
By default, this setting is set excessively high to always enable phase-to-phase
measurement for phase-to-phase-ground faults. This default setting value must be
maintained unless there are very specific reasons to enable phase-to-ground
measurement. Even with the default setting value, phase-to-ground measurement is
activated whenever appropriate, like in the case of simultaneous faults: two ground faults
at the same time, one each on the two circuits of a double line.
One specific situation where the 3I0Enable_PG setting should be altered is for cross-
country faults in high impedance grounded networks, in order to make sure that operation
is phase-to-ground. This is particularly important when using phase preference logic,
since it is only working per phase, not for phase-to-phase measurement. The limit should
be set so that it will be exceeded during a cross-country fault.
8.13 High speed distance protection for series compensated
lines ZMFCPDIS (21)
8.13.1 Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
High speed distance protection zone
(zone 1-6)
ZMFCPDIS
S00346 V1 EN
21
1MRK 506 369-UUS - Section 8
Impedance protection
Line distance protection REL670 2.2 ANSI 383
Application manual
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