How to install an UWP 3.0 system
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1.3.2.2 Retrofit Installation using existing cables
If the installation uses existing cables, it is important to verify the cross section of conductors according
to the above cable section table.
Once the cable size is checked, it is important to ensure that there is no leakage between the two
conductors and, also, no leakage from the conductors to ground or shield.
The best method of leakage testing before connecting any Dupline® modules is to use an insulation tester
(min. 500 V) to verify a resistance higher than 100.000 k
Ω.
1.3.2.3 Cable Routing
The Dupline® cable is a signal cable and it should, therefore, be routed as such. This means that it is
better to keep it separate from power cables, high energy noise sources such as contactors, switched
inductive loads etc. However, if there are no other alternative possibilities, the routing of Dupline ® cable
may pass close to power cables. Should the power cables be very noisy, we suggest using shielded
cables.
1.3.2.4 Cable Splices and Connections
Cable splices are often the source of problems.
It is strongly recommended to splice only cables of the same characteristics (wire cross section,
capacitance, etc). The splicing contact resistance must be as low as possible. Twisted wire splicing under
a wire nut or terminal strip can deteriorate over a certain period of time. It is, therefore, advisable to use
soldering splices. For shielded cable the shield must be continued, but it must not be grounded at the
splicing points. Splices need to be water-tight to prevent the entry of water into the cable, which could
result in increased capacitance.
Note
: Bad splices and/or splices left uncovered, exposed to humid environments, could create critical
problems difficult to route.
During the installation of each module, the length of external cables (input/output) must be selected
according to the datasheet reference.
These wires must be treated as signal wires and be kept away from contactors, relays, motors and other
inductive noise sources. In extreme cases it is necessary to use shielded cable. But here the shield must
also be properly grounded at one point only.
With the high flexibility of Dupline®, external input and output wires should, of course, be kept as short
as possible by bringing the Dupline® bus to the points where signals are to be transmitted or received.
Note: For the dimmer module the cable between the cabinet module and the light should not
exceed 25 metres.
Note
: For input modules with contact inputs, the short circuit current (indicated on the individual
datasheets) must be noted and adequate switching devices must be selected for trouble-free operation.
Note:
if multi-conductor cable is used, where some of the conductors are spare, we highly recommend
connecting all spare wires to ground (preferably close to the
SH2MCG24
). This to reduce the "antenna
effect" of open-end wires.
Recommendations:
1)
Do not connect any of the wires to other voltage potentials.
2)
Do not connect any of the wires to protective earth (PE).
3)
Do not parallel any wires to increase the square of the cores.
4)
Do not use cable gauges larger than 1.5 mm
2
.