Measuring The Operating Limit Of Set Values - Hitachi RED670 Commissioning Manual

1MRK 505 378-UEN Rev. K
Table 29:
Test point
1
2
3
4
5
6
The table showing test points for phase-to-earth loops is used together with figure 31.
Table 30:
Test point
1
2
3
4
5
6
The table showing test points for phase-to-phase loops is used together with figure 32.
11.4.6.1

Measuring the operating limit of set values

Procedure:
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 31. Compare the result
of the measurement with the expected value according to table 29.
The corresponding binary signals that inform about the operation of the phase selection
measuring elements are available in the local HMI under
Line differential protection RED670
Commissioning manual
Test points for phase-to-earth loop L3-E (Ohm/loop)
Value
X [X1+XN]
R 0
X 0
R RLdFw
X 0.85·[X1+XN]
R 0.85·[X1+XN]·1/tan(60°)+RFFwPE
X 0.85·[X1+XN]
R -0.85·[X1+XN]·
tan (AngNegRes-90°)
X RFFwPE·tan (ArgLd)
R RFFwPE
X -0.5·RLdFw·tan (ArgDir)
R 0.5·RLdFw
Test points for phase-to-phase loops L1–L2
Value
X X1
R 0
X 0
R RLdFw
X 0.85·X1
R 0.85·X1·1/tan(60°)+0.5 RFFwPP
X 0.85·X1
R -0.85·X1·tan (AngNegRes-90°)
X 0.5·RFFwPP·tan (ArgLd)
R 0.5·RFFwPP
X -0.5·RLdFw·tan (ArgDir)
R 0.5·RLdFw
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Testing functionality by secondary injection
Comments
XN=(X -X )/3
0 1
R≈0.491·(X1+XN)+RFFwPE
Comments
R=0.491·X1+0.5 RFFwPP
GUID-B1B7DEB6-7BC3-4A90-8D8F-E4E69B434AFA v3
Section 11
113