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4.48
SEL-787 Relay
Instruction Manual
Date Code 20081022
Protection and Logic Functions
Basic Protection
Figure 4.28
I.E.C. Short-Time Inverse Curve: C5
10
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100
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.1
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100
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Time in
Sec
onds
Time in
Cy
cles 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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0.70
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0.90
1.00
Summary of Contents for SEL-787
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