ABB RELION REX640 Technical Manual page 845

1MRS759142 F
Figure 478: MNSPTOC Inverse Curve A
If the negative sequence current drops below the
is defined as:
[ ]
t s
t[s]
a
b
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
REX640
Technical Manual
 
b
= ×
a
 
 
100
Reset time in seconds
Cooling time
set
percentage of start time elapse (
Protection functions
Start value setting, the reset time
)
START_DUR
(Equation 238)
845