Digital Modules
4-42
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Terminal Assignment Diagram of the SM 421; DI 16
120 VAC
1
2
3
4
0
Byte 0
5
6
1
7
8
2
9
10
3
11
13
1N
12
14
15
4
16
17
5
18
19
6
20
21
7
22
24
23
26
27
28
29
30
31
32
33
34
36
35
38
39
40
41
42
43
44
45
46
48
47
25
37
0
1
2
3
4
5
6
7
2N
3N
4N
5N
6N
7N
8N
9N
10N
11N
12N
13N
14N
15N
16N
Byte 1
Adaptation
Process
Module
Data register and bus control
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Adaptation
Figure 4-8 Terminal Assignment Diagram of the SM 421; DI 16
120 VDC