Calrec SUMMA, Installation Manual

Page: 48 / 96

48 SUMMA
Networked Audio Production System
Connection Information
COPPER SFP CONNECTIVITY
Hydra2 network connections can
be made via copper SFP modules.
Copper connections require shielded
F/UTP Category 5e or Category 6
cables with shielded RJ45 mating
connectors. Surface to Core
connections can only be made using
optical/fibre SFP modules.
Calrec do not supply copper 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 EN55022 standard, 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 connector shield connects
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.
Maximumcablelength
The maximum length of Cat5e/Cat6
cables is 90 m/295 ft. 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, fibre 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 practise during
installation can seriously impact upon
this. The following are general rules of
good practise but 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 them out.
• 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 deforms the internal structure
of the cable. Cable ties should be tight
enough to support the cable weight
but not so tight as to cause any visible
deformation to 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 can increase 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.
Termination-strainrelief
Poor termination and lack of strain relief
is one of the most common causes of
high speed network cable problems.
To properly relieve strain on the data
cores, the outer jacket of the cable should
be inserted into the RJ45 housing and
held in place once crimped at the strain-
relief point, as shown in the diagram
above. This also maintains the integrity
of the twist rate and shield into the
termination, ensuring the full length of the
cable conforms to its specification. Slide
on outer boots offer additional strain-relief
protection but are not sufficient on their
own. In order to be able to crimp the cable
jacket inside the RJ45 and land the data
cores on the terminals, the amount that
the jacket is stripped back in relation to
the cores needs to be accurate. Cables
with exposed data cores should not be
used as they will be unreliable.
SHIELDED RJ45 CONNECTOR
Conductive connector mating
screen clamped / bonded to
cable shield
Crimp points
Cable outer jacket
Strain relief
STRAIN RELIEVED RJ45 TERMINATION
• Note, this is a simplified
diagram that does not
include the shield.