INTELLIGENT BRANDS // Cabling
as well as optionally incorporate a data
port for control. For all LED lighting
luminaire configurations, the maximum
power supported by each structured
cabling channel and node, if present,
should not exceed 60W.
A zone cabling design for Power over Ethernet lighting consists of horizontal cable
run from the floor distributor in the server room to an intermediate connection point
called the service concentration point, which is an outlet housed in a zone enclosure
located in the ceiling space.
Due to the density of Power over
Ethernet lighting devices, zone
enclosures typically accommodate 96
service concentration point outlets
and may be designed to replace a
ceiling tile in drop ceiling applications.
A cable or cord connects each service
concentration point outlet in the zone
enclosure to either a service outlet
or directly to a Power over Ethernet
lighting device. In lighting applications,
this type of zone topology, where all of
the Power over Ethernet switches are
located in the server room, is sometimes
referred to as a centralised deployment.
While power levels of up to 100W
may safely be deployed over balanced
twisted-pair cabling, 60W of power is
generally considered to ideally balance
cost, efficiency, and performance in PoE
lighting applications. The technology
supporting power sourcing equipment
and powered devices operating at 60W,
including Cisco UPOE and emerging IEEE
802.3 Type 3 PoE technology, is fully
developed and commercially available.
A cable or cord connects each service concentration point outlet in the zone enclosure
to either a service outlet or directly to a Power over Ethernet lighting device.
cabling and is a safety extra-low voltage
application. This means that the 50-55V
direct current levels used for Power over
Ethernet lighting system circuits pose no
safety risk to the installer, when these
systems are deployed or upgraded, and
no special electrical licensing is required.
Management of multiple building
automation and IP devices over one
network eliminates proprietary cabling,
reduces pathway redundancy, and
supports faster device and system
rollouts and upgrades. Power over
Ethernet lighting systems additionally
benefit from deployment over
structured cabling because they can
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receive centralised back-up power
from the server room and respond
accordingly when integrated with
occupancy, temperature, safety, energy,
and other sensors and systems.
In a smart Power over Ethernet lighting
design, structured cabling connects
an Ethernet switch port capable of
providing DC power directly to an LED
lighting fixture or to a node, which
branches power and data off to an
LED lighting fixtures, a device such as
a sensor, and a controller. Depending
upon the Power over Ethernet lighting
system, troffer size, and manufacturer,
one node may serve one or two troffers
The potential for heat buildup within
cable bundles and electrical arcing
damage to connector contacts
supporting remote powering
applications is well understood, and
the careful selection of cabling and
components for support of 60W PoE
lighting systems can minimise or even
completely mitigate performance
degradation due to these two factors.
While never significant enough to
cause cables to melt or conductors to
short, internal temperature rise within
bundled cables increases conductor
resistance, which leads to power
and efficiency losses, and increased
insertion loss, which may require overall
channel length to be reduced.
Excerpted from Zone Cabling and
Coverage Area Planning Guide: 60W
PoE Lighting Applications, by Siemon.
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