Sel 751A - Figure 4.17 IEC Short-Time Inverse Curve: C5

4.26
SEL-751A Relay Instruction Manual Date Code 20100129
Protection and Logic Functions
Basic Protection
Figure 4.17 IEC Short-Time Inverse Curve: C5
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100
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100
123456789.5 .6 .7 .8 .9
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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
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00