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Figure 478: MNSPTOC Inverse Curve A
If the negative sequence current drops below the
Start value setting, the reset time
is defined as:
t s
a
b
[ ]
= ×
100
(Equation 238)
t[s]
Reset time in seconds
a
set
Cooling time
b
percentage of start time elapse (
START_DUR
)
When the reset period is initiated, the time for which
START
has been active is
saved. If the fault reoccurs, that is, the negative-sequence current rises above the
1MRS759142 F
Protection functions
REX640
Technical Manual
845