Sel SEL-421 - Zone 1 Mho Ground Distance Element Logic Diagram

R.1.51
Date Code 20111215 Reference Manual SEL-421 Relay
Protection Functions
Mho Ground Distance Elements
Figure 1.35 Zone 1 Mho Ground Distance Element Logic Diagram
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+
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+
Relay
Word
Bits
Relay
Word
Bits
Relay
Word
Bit
Relay
Word
Bits
32SPOF
CVTBL
MAG1
MBG1
Z1G
MCG1
XAG1
XBG1
XCG1
32GF
IAL
IGL
mAG1 < Z1MG
FSA
SPO
SPOA
OSB1
OSBA
3PO
67Q1T
ILOP
VPOLV
SERCA
0.1 • I
nom
mAG1 is the Zone 1 A-Phase-to-Ground
Mho Distance Calculation.
A-Phase Mho Ground Distance Logic.
B- and C-Phase Logic Is Similar.