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Chorus Digital Vision - Technical System Manual

The other devices of the video entryphone system must be installed in distribution boards ﬁtted with a DIN rail, or in the Gewiss PTDIN ﬂush-
mounting boxes (for instance GW 48 109). As the PTDIN boxes have a DIN rail, and dividers can be inserted in them, they are ideal when
installing power supplies and switches for the various ﬂoors of blocks of ﬂats or other types of building.

ATTENTION:

the video entryphone system must be kept separate from any data network of the apartment or block of ﬂats.

The coexistence of electric and data cables (LAN)

The DIGITAL VISION System is based on IP technology, and device wiring is regulated by the same rules applied for so-called “structured wiring”.
In particular, it is known that in certain cases there are no alternatives to using the same cable path for laying the data cable (LAN) and the
energy cable. For example, when restructuring or replacing an old video entryphone system there may be only one cable path available for
connecting the front door unit, and the laying of a new, separate one would involve costly work. This gives rise to the problem of whether
and how the data and energy cables can coexist in a single cable path.

What the regulations say

The regulations specify that certain distances must be maintained between data cables and energy cables, for two distinct reasons:

Electrical safety

: for the purposes of electrical safety, the data and energy cables may only be installed in the same cable path (the

same conduit) if the data cable has double insulation. In any case, a LAN cable may coexist with SELV power supply cables (14.4V).

Disturbance immunity

: Standard EN50174-2 deﬁnes the distance to be maintained when laying energy cables and data cables. This

distance varies according to the shielding of the cables and the presence of a metal divider between the cables: the two cables may only be
laid in the same path (same conduit) if they are both shielded. The table below shows the minimum distances from electric supply lines, as
speciﬁed by the above-mentioned standard.

What Gewiss recommends

The Gewiss cables for wiring the DIGITAL VISION system are:

GW 38 189: LAN UTP cable, cat 5e, for indoor wiring

GW 38 195: LAN UTP cable, cat 5e, for outdoor wiring, with double insulation.

To ensure the correct functioning of the system, you are advised to lay the DIGITAL VISION system cables and the energy cables in separate cable paths.
If you need to pass the DIGITAL VISION cable and the energy cable in the same path (same conduit), the only Gewiss cable you can use is the
GW 38 195. The double insulation of this cable guarantees electrical safety, but not disturbance immunity. To obtain full disturbance immunity,
it is necessary for both the data and the energy cable to be shielded. If this is not possible, there may be disturbances due to electromagnetic
couplings and this means the optimum quality performance of the system is not guaranteed.

Cable routes and junction boxes

The cable routes can be chosen on the basis of the cables they must contain. Bear in mind that a shielded data cable usually has a diameter
of about 8mm, and a shielded energy cable (with 3 wires with a section of 2.5mm

)

has a diameter of more than 15mm.

In addition, the cable routes and junction boxes must prevent the cables being subjected to sharp bends.

DESIGN

Positioning the other system devices

Wiring infrastructure

Type of cable

Application ﬁeld: 2kVA - 500V

Without divider

With non-metal

divider

With metal divider