Setting Guidelines - ABB RELION 670 Series Applications Manual

1MRK 504 152-UEN B
The heavy load transfer that is common in many transmission networks may in some cases be
in opposite to the wanted fault resistance coverage. Therefore, FMPSPDIS has an built-in
algorithm for load encroachment, which gives the possibility to enlarge the resistive setting of
both the Phase selection with load encroachment and the measuring zones without interfering
with the load.
The load encroachment algorithm and the blinder functions are always activated in the phase
selector. The influence from these functions on the zone measurement characteristic has to be
activated by switching the setting parameter
zone(s) to
7.8.3

Setting guidelines

GlobalBaseSel : Selects the global base value group used by the function to define ( IBase ),
UBase ) and ( SBase ).
(
INRelPE : The setting of INRelPE for release of the phase-to-earth loop is by default set to 20%
IBase . The default setting is suitable in most applications.
of
The setting must normally be set to at least 10% lower than the setting of
priority to open phase-to-earth loop.
(3I ) that might exist due to un-transposed lines.
0
The setting must also be set higher than the 3I
trip applications.
INBlockPP : The setting of INBlockPP is by default set to 40% of IBase , which is suitable in most
applications.
I1LowLevel : The setting of the positive current threshold I1LowLevel used in the sequence
based part of the phase selector for identifying three-phase fault, is by default set to 10% of
IBase .
The default setting is suitable in most cases, but must be checked against the minimum three-
phase current that occurs at remote end of the line with reasonable fault resistance.
IMaxLoad : The setting IMaxLoad must be set higher than the maximum load current transfer
during emergency conditions including a safety margin of at least 20%. The setting is
proposed to be according to equation 201:
IMaxLoad =1.2 ILoad
EQUATION1614 V2 EN-US
where:
1.2
ILoad
The current ILoad can be defined according to equation 202.
Application manual
On .
is the security margin against the load current and
is the maximal load current during emergency conditions.
LoadEnchMode for the respective measuring
INRelPE must be above the normal un-balance current
that occurs when one pole opens in single pole
0
Section 7
Impedance protection
SEMOD154771-1 v2
SEMOD154782-4 v6
INBlockPP to give
(Equation 201)
245