Setting Parameters - ABB RET670 Applications Manual

1MRK504116-UUS C
3.7.4.3
Table 95: EF4PTOC (51N67N) Group settings (basic)
Name Values (Range)
Operation Disabled
Enabled
IBase 1 - 99999
VBase 0.05 - 2000.00
AngleRCA -180 - 180
polMethod Voltage
Current
Dual
VPolMin 1 - 100
IPolMin 2 - 100
RNPol 0.50 - 1000.00
XNPol 0.50 - 3000.00
INDirPU 1 - 100
2ndHarmStab 5 - 100
BlkParTransf Disabled
Enabled
Use_PUValue ST1
ST2
ST3
ST4
SOTF Disabled
SOTF
UnderTime
SOTF&UnderTime
SOTFSel Open
Closed
CloseCommand
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Application manual
can be chosen very low. As it is required to detect ground faults in the transformer
winding, close to the neutral point, values down to the minimum setting possibilities
can be chosen. However, one must consider zero-sequence currents that can occur
during normal operation of the power system. Such currents can be due to un-
transposed lines.
In case to protection of transformer windings not feeding residual current at external
ground faults a fast lowcurrent step can be acceptable.

Setting parameters

Unit Step
- -
A 1
kV 0.05
Deg 1
- -
%VB 1
%IB 1
ohm 0.01
ohm 0.01
%IB 1
% 1
- -
- -
- -
- -
Default Description
Disabled Disable/Enable Operation
3000 Base value for current settings
400 Base value for voltage settings
65 Relay characteristic angle (RCA)
Voltage Type of polarization
1 Minimum voltage level for polarization in % of
VBase
5 Minimum current level for polarization in % of
IBase
5.00 Real part of source Z to be used for current
polarisation
40.00 Imaginary part of source Z to be used for
current polarisation
10 Residual current level for directional element
in % of IBase
20 Second harmonic restrain operation in % of
IN magnitude
Disabled Enable blocking at parallel transformers
ST4 Current pickup blocking at parallel transf
(step1, 2, 3 or 4)
Disabled SOTF operation mode (Off/SOTF/Undertime/
SOTF&Undertime)
Open Select signal that shall activate SOTF
Section 3
IED application
435