29
General notes on the wiring in DCM audio systems
The cabling depends on the building situation and is only limited by its length.
•
When selecting the cable length consider: the
loop resistance must not exceed max. 20
Ω
(table)
•
To keep within the max. permissible loop
resistance the wire cross section can be
doubled, i.e. two lines are used for one wire
(figure). The lines must be twisted.
•
When using screened cables: connect the
screens to each other and connect on one side
to earth (b wire) on the power supply unit
•
Choice of line or star wiring
Table: Loop resistance
Cross section
Wire length
in m
0.6 mm
0.8 mm
Loop resistance
in
Ω
10
1.22
0.69
20
2.45
1.38
30
3.67
2.07
40
4.90
2.76
50
6.12
3.44
60
7.35
4.13
70
8.57
4.82
80
9.80
5.51
90
11.02
6.20
100
12.24
6.89
150
18.37
10.33
200
24.49
13.78
250
17.22
300
20.66
