Schweitzer Engineering Laboratories SEL-351 - Page 347

Date Code 20001006 Setting the Relay 9-5
SEL-351 Instruction Manual
Figure 9.5: U.S. Short-Time Inverse Curve: U5
Figure 9.6: I.E.C. Class A Curve (Standard
Inverse): C1
Figure 9.7: I.E.C. Class B Curve (Very
Inverse): C2
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