Terminal Connections - ABB REX 521 Technical Reference Manual, General

1MRS 751108-MUM
4.2.6.
Protection Relay
Technical Reference Manual, General

Terminal connections

X3.1
X4.1
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9 9
Data A
RS-485
10 10
Data B
11
12
13
14
15
16
17
18
Service pin 1
X4.2
Tx
X3.2
1
2
3
Rx
4
X3.3
5
6
7
8
9
10
11
12
13
CE
14
15
16
17
18
Made in Finland
Fig. 4.2.6.-1 Rear view of REX 521 Basic
X4.1
X3.1
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
Data A
10
RS-485
Data B 10
11
12
13
14
15
16
17
1
Service pin
18
X4.2
Tx
X3.2
1
2
Rx
3 X3.3
4
5
6
7
8
9
10
11
12
13
CE
14
15
16
17
18
Made in Finland
RearViewMedium
RearViewMedium_a
Fig. 4.2.6.-2 Rear view of REX 521 Medium
1. Service Pin is mounted if the HW version contains LON
X1
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
RearViewBasic_a
1
X1
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
1
REX 521
53