Buildings Arent Wired
the Way They Used to Be...
April 2004 IBEW Journal
Union Electricians
and Contractors have wired countless buildings since electricity
was first harnessed to provide light, energize electric motors
and provide heat in buildings and structures. While the technologies,
which were used to install systems in those buildings have
changed, the basic method of control has, for the most part,
remained the same. Cloth and rubber insulation for conductors
has been replaced by thermoplastics and mineral insulation.
Knob and tube wiring has been replaced by non-metallic sheathed
cable, armored cable, rigid conduit, EMT and PVC. Single-phase
120-volt services have been replaced by 240-volt single-phase,
120/208 volt three-phase, 277/480 volt three phase and other
higher voltage services. With switch loops controlling power
to lights and fans, hard-wired motor control circuits providing
the logic for motor and control applications and systems in
buildings being proprietary and independent of each other,
basic wiring still remains the same. In many buildings being
wired today, security systems cannot talk to energy management
or environmental control systems; components for each system
(energy management, HVAC, security, access control, and lighting)
are proprietary to the manufacturer of that system and building
owners are locked to a single source for parts or a single
manufacturer representative for service for each different
system in the building.
New technologies, however,
are quickly changing the landscape in building design and
function. These new technologies provide the building owner
with enhanced services, and challenge those who design and
wire buildings with thinking "outside of the box"
in replacing their traditional thinking with a new understanding
of how buildings work and what services those buildings can
provide to the user. Users are embracing these new technologies
because of enhanced building performance, reduced energy costs
and simplified building infrastructure. The common feature
of these new technologies is that they no longer depend on
hard-wired (switch loop) designs to provide monitoring or
control of devices or systems. These new building automation
systems (BAS) utilize networked control to provide enhanced
building and system operation at a lower installation cost,
and the building users gain additional benefits in the process.
For instance, 900 feet of concrete was a formidable obstacle
when the San Diego International Airport needed to link a
newly renovated facility with their existing buildings since
the buildings were on opposite sides of the parking lot. To
excavate and bury new control wiring would have been cost
prohibitive and would have interrupted an airport that services
more than 14 million passengers with hundreds of daily flights
year-around. The solution was a networked building automation
system that utilized the airports existing Ethernet network
to provide monitoring and control of the new facilities many
systems. Since the buildings were already connected via Ethernet,
the parking lot did not need to be disturbed.
In Laredo Texas,
the same technology is being used to provide electric utility
customers with the capability of monitoring and controlling
their homes or business electrical power usage by directly
monitoring the hours of peak or off-peak power costs and automatically
controlling their appliances to limit their electric costs.
The Osceola County School District operates 30 schools in
a 1,500 square mile area in central Florida. Their original
systems were proprietary, with multiple vendors for HVAC,
security, fire, lighting, etc. This meant multiple types of
control hardware and software, multiple control configurations,
multiple vendors and sources of components, along
with other similar problems. When the school system needed
to expand, they standardized on a single networked solution
that integrated all of the separate systems into a single
system, eliminating the headaches associated with their previous
designs. New buildings all over the country are utilizing
this networked architecture. The Bellagio Hotel in Las Vegas,
Trump Plaza in New York City, the Westin Hotel in Denver and
the Kennedy Airports FAA facility in Queens all use networked
controls, rather than traditional designs.
 The
networked system that enables these buildings to use network
technology for lighting, energy management, access control,
security, HVAC, etc. is called LonWorks. LonWorks is an open
interoperable platform, which was developed by the Echelon
Corporation, and which enables manufacturers to create many
different devices, called nodes, which can then communicate
over a common network to provide monitoring and control in
a building or system. Hundreds of manufacturers have embraced
this technology and are creating devices which utilize the
LonTalk protocol. The heart of these LonWorks devices is
an integrated circuit chip called a Neuron. The Neuron is
the heart of the LonWorks network, and provides complete distributed
control to any system in which it is installed. Manufacturers
use these Neurons in their devices to enable those devices
to function on a LonWorks network. Hundreds of different manufacturers
make devices that can effortlessly communicate with each other
using the LonTalk protocol. Manufacturers do not need to produce
their own proprietary network solutions, since all of the
work for communication, interfacing, control, etc. has already
been done. This enables the manufacturers to get products
on the shelf faster, with the assurance that they can be used
in the network. Since each device contains its own microprocessor,
each node or device can be programmed to provide specific
services to the system. Since there is no central controller,
there is no central point of failure; and devices can be programmed
to respond to a variety of control scenarios. Given that the
platform for LonWorks is open and interoperable, the manufacturer
(and customer/user) is assured that devices from different
manufacturers can communicate directly with each other.
 Electricians
and Contractors are very familiar with electrical or electronics
systems installed in buildings or projects. LonWorks does
not change that basic premise. What does change, however,
is how those functions are implemented. Rather than wiring
a control device directly to another device that needs to
be controlled, all devices are connected to a common control
network installed in the building. Individuals trained in
programming, called System Integrators, then utilize that
same network to communicate with those devices and define
how the devices will function. The process of programming
a specific LonWorks switch, which is attached to the network,
to control a specific LonWorks lighting controller (relay
or dimmer) attached to the same network; is called binding.
Binding is done using computer and system integration software
available from several different manufacturers. All types
of devices are already available including: switches, relays,
thermostats, passive infrared detectors, VAV controllers,
access control components, HVAC controllers, sensors, motor
drive controllers, etc. Because of the variety of devices
now available, it is possible for every system in a building
to be part of a single network.
The flexibility of
the LonWorks system is not limited to just providing the same
control scenarios, which can be provided with conventional
wiring, however. While it is true that the function of individual
devices can easily be changed simply through programming,
the real value in these networked systems comes in the systems
ability to provide monitoring of the system anywhere on the
network. With the addition of Internet routers, it is possible
to have networks located in physically separated locations
communicating as if they were in the same building. Maintenance
and engineering functions can be centralized in a single location,
often miles or states away from the primary system; rather
than having those functions in each facility. Contractors
and System Integrators can access building functions and perform
troubleshooting or make necessary changes from remote locations
as well. Businesses which have multiple locations can monitor
and control energy, security and environmental functions and
usage from central locations eliminating the need for duplicated
facilities or staff.
The importance of our
understanding of this technology cannot be understated. Because
this technology brings together diverse systems such as HVAC,
security, access control and energy management; many different
competing trades and service providers are moving toward embracing
this technology as their own. The danger lies in the fact
that once a contractor from a particular trade is selected
as the System Integrator for that job, that contractor will
control all devices that are included in the buildings network.
These electrical systems provide control that has been and
is traditionally our work. In order to insure that we continue
to install, service and maintain these systems in the future,
it is imperative that we embrace this technology and learn
how to install and integrate these systems.
The NJATC has offered training classes for
this technology in various locations, including: Upper Marlboro,
MD, the NTI (Knoxville, TN); San Jose, CA, Las Vegas, NV,
Detroit, MI and Sacramento, CA. These classes are open to
IBEW members and NECA Contractors interested in learning this
technology.
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