Current protection
M12336-1 v14
Table 53. Instantaneous phase overcurrent protection PHPIOC
Function Range or value Accuracy
Operate current (5-2500)% of lBase
±1.0% of I
r
at I ≤ I
r
±1.0% of I at I > I
r
Reset ratio > 95% at (50–2500)% of IBase -
Operate time at 0 to 2 x I
set
Min. = 15 ms
Max. = 25 ms
-
Reset time at 2 x I
set
to 0 Min. = 15 ms
Max. = 30 ms
-
Critical impulse time 10 ms typically at 0 to 2 x I
set
-
Operate time at 0 to 10 x I
set
Min. = 5 ms
Max. = 15 ms
-
Reset time at 10 x I
set
to 0 Min. = 25 ms
Max. = 40 ms
-
Critical impulse time 2 ms typically at 0 to 10 x I
set
-
Dynamic overreach
< 5% at t = 100 ms
-
Generator protection REG670
1MRK 502 074-BEN M
78 Hitachi Power Grids
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