Setting Value Remark
IdUnre 3.00 300 % of IBase = 1000 A
Maximum through fault current calculated based on:
220
2.45
3 (4.84 58.64)
ThroughI kA
IECEQUATION15178 V1 EN-US
1.2 1.2 2.45
2.94
1
Through
dUnre
Base
I kA
I kA
I kA
IECEQUATION15179 V1 EN-US
I2/I1Ratio 0.10 Ratio = 10 %
The value can be set this low because the 2
nd
harmonic block is
ignored if an internal fault is detected.
I5/I1Ratio
0.10 Ratio = 10 %
The value can be set this low because the 5
th
harmonic block is ignored
if an internal fault is detected and no tap transformer exists in the
protected zone.
CCCOpMode
1 The exact method with currents and voltages is used. Line
capacitances must be specified.
VTOnLineGrp1 0 VT is placed on the bus.
VTOnLineGrp2 0 VT is placed on the bus.
C0 7.751e-9 x 200 Total zero sequence capacitance of 220kV on a 200 km power line.
C1 12.74e-9 x 200 Total positive sequence capacitance of 220kV on a 200 km power line.
NoOfLineEnds 2 Number of physical line ends in the protected zone (setting used by
charging current compensation).
NoOfCTSetsGrp1 1 Number of three-phase CT groups at first line end, the currents of which
are connected to input group 1 (setting used by charging current
compensation).
NoOfCTSetsGrp2
1 Number of three-phase CT groups at second line end, the currents of
which are connected to input group 2 (setting used by charging current
compensation).
IBase
1000 Nominal current of the protected power line.
NoOfUsedCTs 2 Total number of CT groups in the protected zone.
TapTransformer 0 Tap transformer not included in the protected zone (and its current
therefore not directly measured).
DiffMode Master Differential function activated.
Figure 41 shows the sequence of events after an internal fault. In this example, the
fault occurred at t = 400 ms in the middle of the power line. The operate time in the
example below is obtained from the software algorithm only without considering
the delays due to the hardware and communication.
Section 4 1MRK 505 382-UEN B
Analog and binary signal transfer for line differential protection
50 Communication set-up 670/650 series 2.2
Application Guide
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