Table 69. Stabilized and instantaneous differential protection for machines (MPDIF)
Characteristic Value
Operation accuracy Depending on the frequency of the current measured: f
n
±2 Hz
±3% of the set value or ±0.002 x I
n
Operate time
1)2)
Minimum Typical Maximum
Low stage
36 ms 40 ms 42 ms
High stage 18 ms 22 ms 27 ms
Reset time <40 ms
Reset ratio Typically 0.95
Retardation time <20 ms
1) F
n
= 50 Hz, results based on statistical distribution of 1000 measurements
2) Includes the delay of the power output contact
Table 70. Stabilized and instantaneous differential protection for machines (MPDIF) main settings
Parameter
Function Value (Range) Step
Low operate value MPDIF 5...30 %Ir 1
High operate value MPDIF 100...1000 %Ir 10
Slope section 2 MPDIF 10...50% 1
End section 1 MPDIF 0...100 %Ir 1
End section 2 MPDIF 100...300 %Ir 1
DC restrain enable MPDIF 0 = False
1 = True
-
CT connection type MPDIF 1 = Type 1
2 = Type 2
-
CT ratio Cor Line MPDIF 0.40...4.00 0.01
CT ratio Cor Neut MPDIF 0.40...4.00 0.01
Table 71. Third harmonic-based stator earth-fault protection (H3EFPSEF)
Characteristic
Value
Operation accuracy Depending on the frequency of the measured voltage:
f
n
±2 Hz
±5% of the set value or ±0.004 × U
n
Start time
1)2)
Typically 35 ms
Reset time Typically 35 ms
Reset ratio Typically 0.96 (differential mode)
Typically 1.04 (under voltage mode)
Operate time accuracy ±1.0% of the set value of ±20 ms
1) f
n
= 50 Hz, results based on statistical distribution of 1000 measurements
2) Includes the delay of the signal output contact
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