17
The secondary current of the current trans-
former is to be selected on the basis of the rated
current, 1 A or 5 A, of the relay energizing input
to be tested. The energizing inputs are specified
in chapter "Technical data" under the heading
"Energizing inputs".
≅
5A
1A
SPAJ 111 C
U2
U3
11
11
D
CB
A
25
SGR/1
U3
+
-
E
_
10
11
61
62
71
72
70
78
77
81
80
69
68
66
65
SGR
7
5
6
8
3
2
4
SIGNAL1
TRIP2
TRIP1
26
27
IRF
Uaux
+
(
~
)
-
(
~
)
A
TIMER START
S1
L1
N
S2
L2
L3
BS
START1
TIMER STOP
IRF
L1
L4
TS2
TS1
SGB
SS1
SS2
U1
5
4
I/O
t >>
t >
Io>
Io>>
73
74
75
START2
Fig. 7. Secondary injection test circuit for the earth-fault relay SPAJ 111 C.
When the test circuit has been completed and
the selector switches have been properly set, the
auxiliary voltage is connected to the relay. The
operation of the test circuit can be verified by
using a multimeter.