How to install a Sx2WEB system
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1.2.3 Cable and installation tips
1.2.3.1 New Installation Planning
When planning a new installation, a generic Bus cable can be used: it is better to use a twisted cable in
order to prevent electrical noise from affecting one conductor more than the other and thereby creating
an unbalanced Dupline®
system.
In the case of very noisy installations (with noise sources such as contactors, inductive loads etc) we
recommend the use of a shielded cable.
The table below can be used to find the right cable: this can easily be carried out by considering the
maximum distance between the SH2MCG24 and the farthest module in the installation and checking
the table below.
The values shown in the table have been calculated considering a balanced distribution of the modules
in the Dupline® bus.
Installations where most of the modules are placed at the end of the network may be critical and this is
not recommended (the table is not valid in this case).
The values shown in the table are also suitable for installations where the majority of the modules are
placed at the beginning of the network (close to the SH2MCG24); this type of connection represents the
best configuration to guarantee the best performance of the system.
Table of cable sections:
Max current
Consumption
Cable size
0.75 mm
2
(AWG 19), twisted
1 mm
2
(AWG 17),
twisted
1.5 mm
2
(AWG 15), twisted
450 mA
50 m
70 m
100 m
350 mA
65 m
90 m
130 m
300 mA
75 m
100 m
150 m
250 mA
90 m
120 m
180 m
200 mA
115 m
150 m
230 m
150 mA
150 m
200 m
300 m
100 mA
225 m
300 m
450 m
50 mA
450 m
600 m
900 m
The user is recommended to select cables according to the length and consumption shown in the table
above. It is also advisable to use polyethylene conductor insulation to have lower cable capacitance.
The total consumption of all the modules supplied by the Dupline® bus (e.g. light switch, PIR, lux
sensors) and the cable resistance affect the voltage of the Dupline® bus.
The drop in the Bus voltage might cause the modules placed far from the SH2MCG24 to not work
correctly.
