Schweitzer Engineering SEL-351P, Quick Start Manual

Page: 168 / 674

iv Overcurrent, Voltage, Synchronism Check, and Frequency Elements Date Code 990430
SEL-351P Manual Técnico
Figure 3.24: Synchronism Check Voltage Window and Slip Frequency Elements ................................3-37
Figure 3.25: Synchronism Check Elements.............................................................................................3-38
Figure 3.26: Angle Difference Between V
P
and V
S
Compensated by Breaker Close Time (f
P
< f
S
;
V
P
shown as reference in this example).......................................................................3-42
Figure 3.27: Undervoltage Block for Frequency Elements .....................................................................3-46
Figure 3.28: Levels 1 through 6 Frequency Elements .............................................................................3-47