Date Code 20011205
Distance and Overcurrent Elements
3-3
SEL-311A Instruction Manual
I • X
I • R
Vmem
Z
•
I
V
Restrain
cos (
q
) < 0
(Z • I - V)
I • Z
source
Test Angle
cos (
q
) > 0?
Balance
cos (90
°
) = 0
I • X
I • R
Vmem
Z
•
I
V
(Z • I - V)
I • Z
source
Test Angle
cos (
q)
> 0?
Operate
cos (
q
) > 0
I • X
I • R
Vmem
Z
•
I
V
(Z • I - V)
I • Z
source
Test Angle
cos (
q
) > 0?
Forward External Fault
Forward Fault at the Balance Point
Forward Internal Fault
M311B034
Figure 3.1: Positive-Sequence Polarized Mho Element
Summary of Contents for SEL-311A
Page 6: ......
Page 8: ......
Page 10: ......
Page 24: ......
Page 40: ......
Page 66: ......
Page 96: ......
Page 98: ......
Page 112: ......
Page 114: ......
Page 122: ......
Page 170: ......
Page 202: ......
Page 204: ......
Page 246: ......
Page 248: ......
Page 286: ......
Page 290: ......
Page 304: ......
Page 306: ......
Page 334: ......
Page 384: ......
Page 386: ......
Page 394: ......
Page 398: ......
Page 402: ......
Page 404: ......
Page 410: ......
Page 412: ......
Page 426: ......
Page 444: ......
Page 460: ......
Page 474: ......