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It is precisely the widely distributed network of DDC stations The universal cabling system comprises the following func-
and the associated integration into building control systems tional elements:
which offer a large target for interference caused by lightning ¨ Campus distributors (CD)
currents and surges. If this causes failure of the entire lighting,
air-conditioning or heating control system, this failure does not ¨ Campus backbone cables
only cause primary costs for the equipment, but also entails high ¨ Building distributors (BD)
costs for the consequences of this system failure. It can signifi- ¨ Building backbone cables
cantly increase the energy costs since peak loads can no longer ¨ Floor distributors (FD)
be analysed and optimised due to the fault in the control elec-
tronics. If production processes are integrated in the BA, dam- ¨ Horizontal cables
age to the BA can lead to production downtimes and thus to ¨ Consolidation point (optional) (CP)
high economic loss. To ensure permanent availability, protection ¨ Telecommunications outlet (TO)
measures are required which depend on the risk to be controlled.
Groups of these functional elements are interconnected to
form cabling subsystems.
8.2.3 Generic cabling systems (computer Generic cabling systems contain three subsystems: The campus
networks, telecommunication systems) backbone, building backbone and horizontal cabling system.
The European standard EN 50173 “Information technology – These cabling subsystems are interconnected to form a generic
Generic cabling systems” defines a universal cabling system cabling structure as shown in Figure 8.2.3.1. The relevant
which can be used at locations with one or more buildings. distributors allow any network topology such as bus, star, tree
It deals with cabling systems consisting of balanced copper and ring.
cables and optical fibre cables. This universal cabling system The campus backbone cabling subsystem extends from the
supports a wide range of services including voice, data, text campus distributor to the building distributors which are
and images. typically located in separate buildings. If present, it includes
the campus backbone cables, their terminations (both at the
It provides: campus distributor and building distributors) and the cross-
connects in the campus distributor.
¨ An application-independent and universal cabling system
and an open market for (active and passive) cabling com-
ponents A building backbone cabling subsystem extends from building
distributor(s) to the floor distributor(s). It includes the build-
¨ Users with a flexible cabling topology that allows to easily ing backbone cables, their mechanical terminations (both at
make changes in a cost-effective way
the building distributor and floor distributors) and the cross-
¨ Building installers with a guideline which allows to in- connects in the building distributor.
stall the cabling before specific requirements are known
(namely at the design stage irrespective of which platform The horizontal cabling subsystem extends from the floor dis-
is installed later) tributor to the telecommunications outlet(s) connected to it. It
¨ The industry and standardisation committees for network includes the horizontal cables, their mechanical terminations
applications with a cabling system, which supports current at the floor distributor, the cross-connects in the floor distribu-
products and forms a basis for future product development. tor and the telecommunications outlets.

CD BD FD CP TO
(optional)

campus backbone building backbone horizontal work area terminal
cabling subsystem cabling subsystem cabling subsystem cabling device

universal cabling system

Figure 8.2.3.1 Generic cabling structure

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