ABB RELION RET670, Installation And Commissioning Manual

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Table 23: Test points for phase-to-phase loops L1–L2
Test point Value Comments
1 X X1
R 0
2 X 0
R RLdFw
3 X 0.85·X1 R=0.491·X1+0.5 RFFwPP
R 0.85·X1·1/tan(60°)+0.5 RFFwPP
4 X 0.85·X1
R -0.85·X1·tan (AngNegRes-90°)
5 X 0.5·RFFwPP·tan (ArgLd)
R 0.5·RFFwPP
6 X -0.5·RLdFw·tan (ArgDir)
R 0.5·RLdFw
The table showing test points for phase-to-phase loops is used together with figure
55 .
13.5.2.1 Measuring the operate limit of set values
1. Supply the IED with healthy conditions for at least two seconds.
2. Apply the fault condition and slowly decrease the measured impedance to
find the operate value for of the phase-to-earth loop L3, test point 1,
according to figure
54 . Compare the result of the measurement with the
expected value according to table 22 .
The corresponding binary signals that inform about the operation of the phase
selection measuring elements are available in the local HMI under
Main menu/Test/Function status/Impedance Protection/
PhaseSelection(PDIS, 21)/PHSx
.
3. Repeat steps 1 to 2 to find the operate values for the remaining test points
according to figures 54 and table 22 .
When the load encroachment characteristic is deliberately set
very high in order not to have an influence, then the test points
2 and 5 can be replaced by test point 7.
4. Repeat steps 1 to 3 to find the operate value for the phase-to-phase fault in L1
— L2 according to figure 55 and table 23 .
Section 13
1MRK 504 088-UEN C
Verifying settings by secondary injection
124
Installation and commissioning manual