Figure 3.2-11 Single End Fed Fault Rf Mode, Positive Half Cycle; Figure 3.2-12 Single End Fed Fault Rf Mode, Negative Half Cycle - Siemens Solkor 7PG2113 Technical Manual

R a
A
+
-
+
O
-
D5
W
A
O
W
A
D1
-
O
+
-
+
W
R a
W
O
A

Figure 3.2-12 Single End Fed fault Rf mode, negative half cycle

The single end fed internal fault conditions configure the circuit in a similar way to the double end fed internal fault
but only one summation transformer has any output. Thus the other summation transformer acts only as an
equalising transformer, re-circulating current through the measuring element as indicated in Figure 3.2-11 &
Figure 3.2-12. The voltage distribution shows diagrammatically how, in each half cycle, the measuring elements
are energised via R at the energised end and the action of the remote end summation transformer re-circulating
a
current via the polarising diodes D4 on one half-cycle and D8 on the other half-cycle.
©2010 Siemens Protection Devices Limited
R p
B
D3
R p
X
B
X

Figure 3.2-11 Single End Fed fault Rf mode, positive half cycle

B
R p
D7
X
R p
X
B
7PG2113/4/5/6 Solkor Description of Operation
R
C a
D4
Y
R a
C
Y
C
R a
D8
Y
R a
Y
C
D
P
Z
D
P
Z
D
P
Z
Z
P
D
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