Network Cabinet Design and Location
The cabinets or enclosures are usually installed in equipment rooms located
at strategic points within the building. In a well designed system, their location
will ensure that horizontal cable runs are maintained within the 90M maximum run
length, with easy access to the vertical risers.
The example shown in Figure 1 details a typically well designed cabinet layout.
It should be noted that adequate panel management should always be provided to
avoid messy patch cable situations.
Permanent cable entering the cabinet should be managed on trays located either
side of the cabinet. This tray provides support for horizontal cables or cabinet
to cabinet cabling, allowing neat and technical superior stress free terminators
To void congestion on one particular side of the cabinet, cables should be
fed to panels and equipment from alternative sides.
It is possible that cables could enter the cabinet from either above or below,
in any event attention should be paid to the bend radius of those cables and where
cables leave, tray protection should be provided from sharp edges that could damage
them. This protection is normally in the form of roll off edges.
Where active and passive equipment are to share the same cabinet, consideration
should be given as to whether active or passive equipment location is at the top
or bottom of the cabinet.
Passive equipment should always be closest to the point of entry in the cabinet,
typically this would be at the bottom of a cabinet allowing the location of active
equipment to be at a more convenient height for set up and network monitoring
etc. Where cables enter from the top of the cabinet, then serious consideration
should be given to the provision of a separate cabinet for the active product.
If economics do not allow for this, ensure that horizontal cables are well clear
of the sides of the cabinet where the active products will be located, as failure
to do this may prevent the subsequent instillation of active equipment.
To ensure that the instillation is user friendly, labelling of ports is essential.
This requires the production of labels strips that identify patch panel ports
and active panel ports
Details of these port IDs are normally maintained is a software package called
"Cable Management Software". Various packages are available.
Equipment room location and subsequent layout of cabling within it are decided
by the network designer at an early stage and should allow for distribution on
the horizontal to be within the maximum run limits.
It may be necessary in large buildings to have more than one equipment room
per floor. This may lead to the requirement for "Tie" cables to be installed
between the equipment rooms to gain access to the full range of active equipment
within the network.
In sensitive commercial business such as banks and dealer rooms or computer
control rooms, it is often desirable to support network users by different active
elements within the network to avoid complete breakdowns in communications should
active equipment fail.