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5.119
Date Code 20171021
Instruction Manual
SEL-421 Relay
Protection Functions
Switch-Onto-Fault Logic
Figure 5.90
SOTF Logic Diagram
52AEND
ESPS
TF := Y
0
CL
OEND
0
5
CY
C
0
0
SO
TFD
SO
TFE
R
eset
0
SO
TFD
SPO
3PO
R
ela
y
Wo
rd
Bit
52AEND := OFF
Set
tings
CL
OEND := OFF
CLSMON
EVRS
T := Y
VA1FM
VRS
TPU • VNOM
0.
1
SPO
A
SPOB
SPOC
Set
ting
3V
A2FM
3•
VA1FM
Set
ting
SEL
OGIC
Set
ting
R
ela
y
Wo
rd
Bits
Summary of Contents for SEL-421-4
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