Sel SEL-421 - Page 125

R.1.83
Date Code 20111215 Reference Manual SEL-421 Relay
Protection Functions
Inverse-Time Overcurrent Elements
Figure 1.57 IEC Short-Time Inverse—C5
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100
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Time in Seconds
Time in Cycles 60 Hz (50 Hz)
6000 (5000)
3000 (2500)
1500 (1250)
600 (500)
300 (250)
150 (125)
60 (50)
30 (25)
15 (12.5)
6 (5)
3 (2.5)
Multiples of Pickup
0.05
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0.90
1.00