NEC 2400 Integration Manual page 41

Worksheet B: Extension/LTN Plan
Extension
Determining the Extension/Logical Terminal Number Plan
LTN Extension
1
3
5
7
9
11
13
15
17
19
21
23
25
27
29
31
33
35
37
39
41
43
45
47
49
51
53
55
57
59
61
63
LTN
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
40
42
44
46
48
50
52
54
56
58
60
62
64
Issue 2 December 1995
3-5