Calrec Hydra2, Руководство по установке

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32 HYDRA2
Installation Manual
Hydra2 network connections and
control surface to processing rack
connections made via copper SFP
modules require shielded F/UTP
Category 5e or Category 6 cables with
shielded RJ45 mating connectors.
Calrec do not supply these cables as it is
often preferable to terminate them after
they have been run through cable ducting
to avoid damaging the terminations, and to
be able to cut them to the precise length
required.
Shieldedcablesandconnectors
Shielded cabling and connectors are
required in order to meet EMC (Electro-
magnetic compatibility) standards to
comply with the Class B radiated emission
limits set in the standard EN55022, as
well as to guarantee performance in
electrically noisy environments.
F/UTP Cat5e/Cat6 cable has an overall
foil shield around the conductor cores.
Shielded RJ45 connector plugs have a
metallic shield around them which should
be clamped / bonded to the shield within
the cable. The shield on the connector
mates with the chassis of the RJ45
socket that it is plugged into, providing an
earth to the cable shield.
The method of attaching the connector
shield to the cable shield can vary. Please
refer to the connector manufacturer’s
information for further guidance.
RJ45 COPPER SFP CONNECTIVITY
SHIELDED RJ45 CONNECTOR
Conductive connector mating
screen clamped / bonded to
cable shield
Maximumcablelength
The maximum length of Cat5e/Cat6
cables is 100m / 328ft. This is the
absolute maximum and needs to include
any patch points and cables that may be
in the path. Hydra2 cable runs can NOT
be extended using Ethernet switches,
hubs or repeaters. If a run between
Hydra2 hardware exceeds the maximum
recommended distance for copper
cabling, fiber and optical SFPs should be
used instead.
Cableroutingconsiderations
The layout and twist rate of the data cores
within Cat5e/Cat6 cables are integral
to their performance at high speed over
distance. Poor installation practise can
seriously impact upon this. The following
are general good rules of practise,
please refer to the cable manufacturer’s
information for comprehensive installation
rules:
• When running Cat5e / Cat6 network
cabling, it is important to avoid kinking
the cable. Kinks can seriously impair
performance. Cable manufacturers
advise that kinked cables should be
discarded and replaced as the damage
caused cannot be addressed simply by
straightening the outer appearance.
• Cables should not be bent in tight
angles, this too can seriously impair
performance. Please refer to the
cable manufacturer’s specification on
minimum bend radii.
• Excessive pulling force when routing
cables can deform the twist rate of
the cable cores, causing irreparable
damage. Cable manufacturers specify
a maximum pulling tension.
• Cable ties should not be over-tightened
as this also deforms the internal
structure of the cable. Cable ties
should be tight enough only to support
the cable weight but not so tight as
to cause any visible deformation to
Crimp points
Cable outer jacket
Strain relief
STRAIN RELIEVED RJ45 TERMINATION
the cable’s outer jacket. Large, heavy
bundles of cables can be difficult
to support using cable-ties without
causing damage. “Velcro” style hook-
and-loop cable straps can be a good
alternative to plastic cable ties.
• Whilst neatly bundled parallel cable
runs are tidy and aesthetically pleasing,
they increase the chance of cross-talk,
which can impact on performance.
Avoid neat bundling of network cables
over any kind of distance—the majority
of a cables length is normally unseen,
running under floor or through ducting
where they should be loosely laid rather
than neatly bundled.
Terminationandstrainrelief
Poor termination and lack of strain relief
is one of the most common causes of
high speed network cable problems.
To properly strain relief the data cores,
the outer jacket of the cable should be
inserted into the RJ45 housing and held
in place once crimped by the strain-relief
point, as shown in the following diagram.
This also maintains the integrity of the
twist rate and shield into the termination,
and therefore the full length of the cable
• Note, this is a simplified
diagram that does not
include the shield.