Schweitzer Engineering Laboratories SEL-700G Series, Instruction Manual

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4.79
Date Code 20170814 Instruction Manual SEL-700G Relay
Protection and Logic Functions
Group Settings (SET Command)
78R2 are retained until the next time SWING asserts, which is the next time a
power system swing occurs.
Figure 4.47 Single-Blinder Scheme Logic Diagram
The sum of the forward and reverse reaches (the diameter of the mho circle)
has to be 100 ohms or less for a 5 A relay and 500 ohms or less for a 1 A relay.
The blinder settings must be greater than or equal to five percent of either the
forward or the reverse reach, whichever is greater.
Set
ting
Rela
y
Wo
rd
Bits
SEL
OGIC
Set
ting
0
0.
5
CY
C*
0.
5
CY
C*
0
0.
5
CY
C*
0
0.
5
CY
C*
0
_
+
_
+
_
+
1
1 1
Set
ting
Set
ting
The logic is pr
oc
essed when V1X > 0
.2
5V
, all timer
s and elements ar
e r
eset when V1X < or = 0
.2
5 V
.