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TECHNICAL INFORMATION
Technical information
Data Compliant Trunking
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Installation guidance
Laying vs pulling
It is important to consider the
installation method prior to installing
data cables. Incorrect method or poor
installation techniques can alter the
cable characteristics and degrade the
overall specification of the data cable.
When pulling cables into trunking
systems it is important to note the
manufactures maximum pulling force
as this can reduce the minimum bend
radii of the data cable. Laying data
cables into a trunking system ensures
that minimum bend radius can be
achieved and that the data cables
installed complies with the required
specifications for the installation.
Types of screening available
Materials of screening
The shielding of data cables is
important as this stops the signal
generated within the data cable
radiating and interfering with signals
in nearby cables and circuitry. The
shielding also protects the signal from
surrounding cables and other external
influences. The two main types of
shielding material are metallic foil and
metallic braid. A number of factors
should be considered before selecting
the type of shielding for an installation.
• The flexibility of the data cable
• The mechanical strength
• The required shield effectiveness
• Ease of stripping and terminating
Once the correct type of shielding has
been selected it is important that the
shielding is bonded correctly for it to
be effective in protecting against signal
interference.
PVC-U vs Aluminium trunking
Advantages/disadvantages
PVC-U trunking systems are low cost,
light weight and can be easily
fabricated whilst on site, however
PVC-U is a nonconductive material
so offers no protection against EMI.
When using a PVC-U trunking for data
installation it is important to segregate
and screen the data cables from power
and control cables.
This can be easily overcome by either
using our range of conductive copper
sprayed multi compartment trunking
systems or by using the steel screening
divider. Steel screening dividing strips
can be easily retro fitted to an existing
PVC-U trunking installation.
Aluminium trunking systems are
lightweight and easy to handle and
have high impact and mechanical
strength compared to a PVC-U trunking
installation. Aluminium trunking
systems offer great protection against
EMI especially at higher frequencies.
Both material options aid and support
compliant installations.
Data cable types
Advantages/disadvantages
Advantages
• Screened cables offer better
protection against electromagnetic
interference compared to un-
screened data cables.
• Screened and unscreened cables
work fine at 1Gigabit Ethernet data
rates but screened data cables
will outperform at data rates such
as 10Gigabit due to their ability
to support higher frequency
transmissions
Disadvantages
• Unscreened data cables require a
physical barrier and or separation
distance between power cables
must be increased.
Data aperture sizes –
LJ6C and Euro modules
LJ6C data modules are suitable for
use in trunking systems, floor boxes
or any systems that has an industry
standard LJ6C aperture. The aperture
size for the LJ6C module is 22mm x
37mm but may differ slightly between
manufacturers. The Euro data modules
have a slightly larger aperture at 25mm
x 50mm. Coordinating accessory plates
can accommodate one or multiple
Euro data modules.