WHITE PAPER
CCTV POWER OVER
STRUCTURED CABLING
AND THE STANDARDS
WHICH APPLY
NITEK
®
Introduction
Since the early 90’s we have seen enormous growth in our
telecommunications industries and the equipment. Before this
time our communication infrastructure was relatively simple,
but now Structured Cabling has become the standard for
communication wiring both in the United States and around
the world. This Structured Cabling explosion has allowed us to
connect with everything from our telephone and computer to
televisions and video cameras. CCTV has taken advantage of
Structured Cabling for transmission of video signals for many
years. In recently years Structured Cabling is also becoming
an easy pathway for powering of equipment. These powered
devices include CCTV cameras, PA speakers, and even
access control equipment. Due to this we are no longer
dealing with low voltage communication signals, but instead
equipment which can pull serious amounts of power. Because
Structured Cable is only rated to handle Class 2 circuits we
need to be vigilant as to what equipment is connected and
what regulations may apply.
This paper is intended to look at National Electrical Code
(NEC)1 requirements for power source equipment as it
pertains to Structured Cabling. It will explain how to determine
if equipment meets NEC requirements and address some of
the common misconceptions about power source equipment
suitability for use with Structured Cabling.
Work on the NEC is sponsored by the National Fire Protection
Association (NFPA). The NEC is developed by NFPA's
Committee on the National Electrical Code, and is approved
by the American National Standards Institute (ANSI). The NEC
is the United States standard for the safe installation of
electrical wiring and equipment. It is formally identified as
ANSI/NFPA 70. While the NEC is not itself a U.S. law, it is
commonly mandated by state or local law, as well as in many
jurisdictions outside of the United States.
1
"National Electrical Code" and "NEC" are registered trademarks of the NFPA. For the purposes of this paper all NEC code
references specify paragraphs in the 2008 edition. The requirements have been in NEC for many years but specific paragraph
references may have changed.
NITEK®
www.nitek.net
Rev Number:v1.0
Date: 07/07/2008
Copyright 2008 Nitek
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The primary section of the NEC that deals with Structured
Cabling and its power requirements is Article 7252. This
section divides circuits into three separate Classes according
to the level of energy a circuit can carry and how safe it is to
work with. As mentioned Structured Cable is Class 2. Class 2
circuits are the safest, due to power limitations. Of particular
interest are two restrictions that the NEC places on installers
and users of Class 2 wiring. The first is that only Class 2
power supplies may be connected to Class 2 wiring3. The
second states that, any Class 2 supply must be clearly
marked4.
How does this apply to a CCTV system which operates over
the structured Cabling of the building? First, it means that only
equipment which has a Class 2 power output may be used.
Second, if equipment is not marked Class 2 it may not even be
connected to the Structured Cabling. Violating these rules is
against the National Electrical Code. If discovered, offending
equipment must be modified or replaced with Class 2
equipment immediately. These rules of course require
manufacturers of power source equipment to mark their
equipment as to its power output and class.
Nitek invented the concept of powering CCTV equipment over
structured cabling and has been awarded 3 separate patents
on technologies used for operating and powering CCTV over
Structured Cabling5. All of Nitek UTPLinks6 equipment has
been designed to comply with the NEC. Currently Nitek is the
only manufacturer who can make these statements.
Additionally, all the Nitek UTPLinks is UL Listed7 Class 2
equipment.
While many municipalities do require the installation of UL
Listed equipment, one of the common misconceptions is that if
a piece of equipment has the UL Mark it must be Class 2 or it
2
Article 725 addresses Class 1, Class 2 and Class 3 Remote-Control, Signaling, and Power-Limited Circuits
NEC2008 725.130 (B) Class 2 and Class 3 Wiring Methods
4
NEC2008 725.124 Circuit Marking
5
Patents 7,193,149 System Handling Video, Control Signals and Power; 7,312,811 Video Communication
System; and 7,339,111 System Handling Video, Control Signals and Power
6
UTPLinks is a Registered Trademark of Nitek
7
UL is a trademark of Underwriters Laboratories Inc. is an independent product safety certification
organization that has been testing products and writing Standards for Safety since 1894.
3
NITEK®
www.nitek.net
Rev Number:v1.0
Date: 07/07/2008
Copyright 2008 Nitek
3
is approved for connection to structured cable. While UL
evaluates products for compliance with specific safety
requirements, UL certification does not guarantee the product
will perform acceptably or that it meets the NEC. Meeting the
NEC is as much a function of proper installation as it is proper
equipment design. In the case of CCTV equipment design for
use with Structured Cabling, most manufactures do not even
have a UL Listing. Further, most do not manufacture a
complete solution. This leaves the installer having to search
for equipment from several manufacturers that would work
together and yet still meet the NEC. Another unique
advantage to Nitek is complete camera to head-end solution
which is fully up-gradable to IP if or when the user chooses to
go that route.
One advantage to UL Listed equipment is that, UL does test
the outputs of equipment and if equipment is marked on the
equipment as Class 2 you can be sure of what you have.
Conclusion
NITEK®
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Connecting anything other then a Class 2 power source to
structured cabling compromises the cabling and violates the
National Electrical Code. If discovered, offending equipment
must be modified or replaced with Class 2 equipment
immediately. Nitek is currently the only company providing a
full and complete solution which meets NEC requirements.
Additionally, it is fully up-gradable to IP.
Rev Number:v1.0
Date: 07/07/2008
Copyright 2008 Nitek
4
References:
1) National Electrical Code. NFPA 70 National Electrical Code 2005
Edition. National Fire Protection Association, 2004.
2) National Electrical Code. NFPA 70 National Electrical Code 2008
Edition. Quincy: National Fire Protection Association, 2007.
3) "UL Certifications Directory." www.ul.com. Underwriters Laboratories
Inc. 10 July 2008 <http://database.ul.com/cgibin/XYV/template/LISEXT/1FRAME/index.htm>.
4) Underwriters Laboratories. UL 2044. Northbrook: Underwrites
Laboratories Inc., 1997.
5) Underwriters Laboratories. UL 60005. Northbrook: Underwriters
Laboratories, 2003.
NITEK®
www.nitek.net
Rev Number:v1.0
Date: 07/07/2008
Copyright 2008 Nitek
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