Figure 1-1 Functional Diagram Of 7Sr21 Relay - Siemens 7SR21 Manual

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37
49
(x2)
I
L1
(I )
A
37
49
(x2)
I
L2
(I )
B
37
49
(x2)
I
L3
(I )
C
46
46
NPS
BC
(x2)
I
4
(I /I )
64 50G
G SEF
REF (x2)
Optional
79
Figure 1-1 Functional Diagram of 7SR21 Relay
7SR21 & 7SR22 Argus Description of Operation
7SR21
81 60
50 50 51
HBL CTS-
BF (x2) (x2)
2 I
81 60
50 50 51
HBL CTS-
BF (x2) (x2)
2 I
81 60
50 50 51
HBL CTS-
BF (x2) (x2)
2 I
81
50N 51N
HBL
(x2) (x2)
2N
50 51
51G 37G
SEF SEF
(x2) (x2)
(x2) (x2)
74
TCS
Chapter 1 Page 8 of 71