Recreational Equipment Inc. recently opted for an EIA/ANSI standard fiber optic network to support “smart” systems at its expanded headquarters campus north of Seattle, Wash.
The benefits of high-bandwidth fiber optic networks are well known in the telecommunications industry for their ability to carry large quantities of data at high speeds. But increasingly, building engineers and systems integrators are discovering that fiber optics is also the most efficient, reliable and secure networking solution for their building automation, security, fire and energy management systems.
Fiber optics, which transmits data digitally in the form of light, not electricity, is not only an intrinsically safe and more reliable medium than traditional copper wire-based building automation systems, it is the medium of choice for large projects such as high-rise buildings and building campuses that need high throughput backbones to communicate reliably between multiple floors and buildings.
Today’s intelligent buildings are electronically enhanced to automatically control critical building functions, such as lighting, heating, ventilation, air conditioning and power supplies as well as fire protection, access control and security. Building engineers, owners and facilities managers who want to improve the safety, comfort and environmental quality of their projects and at the same time improve energy efficiency are increasingly turning to the EIA/ANSI 709 LonWorks open standard to link their critical building functions.
In large, complex infrastructures, heavy communications traffic and interference can overload even the best building automation system, especially in periods of peak activity or when critical message traffic adds to the load. The problem is exacerbated when links between buildings run through the same conduits as power cables, which are a major source of electromagnetic interference. And in some cases, the links are simply too long for copper wires to handle without repeaters.
One way of getting around this problem is to link LonWorks subsystems by means of Ethernet using traditional twisted pair interconnects. But the limitations and vulnerability of copper are still there – links between multiple buildings, high-noise environments, rooftops and backbones linking together many subnets or floors in large buildings.
‘Smart systems’
The preferred solution is to use an all-fiber-optic LonWorks backbone, built from fiber-to-twisted-pair routers that weave twisted pair subnetworks into a redundant fiber optic backbone network. A single Ethernet to LonWorks port provides visibility from the Ethernet network without making the system critically dependent upon Ethernet. With fiber backbones, building safety and security functions no longer rely on the building’s information technology infrastructure. So, if the server goes down, the entire building is not affected … and you don’t need to find the IT manager to bring your security or access control system back on-line.
When the backbone of a building automation system is a stand-alone fiber optic network, the control system is immune to all the problems inherent in copper media. The system is capable of handling heavy traffic over long distances without repeaters, and it is not affected by power spikes or failure, system overload, cable damage or even interference from lightning and high-power electromagnetic pulses that can bottleneck or cut the flow of twisted-pair-based networks.
Recreational Equipment Inc., one of the biggest sports outfitters in the Unites States, recently opted for an EIA/ANSI standard fiber optic network to support smart systems in its new, expanded headquarters campus north of Seattle, Wash. REI facilities managers wanted a state-of-the-art campus with controls that would enable the company to automate multiple functions from disparate sources, including HVAC and lighting, to achieve maximum energy efficiency. They also needed controls for a fireplace and water pumps that feed a mock river running through the campus, a fitting architectural addition that honors the company’s ties to nature and the great outdoors.
One challenge for REI was in linking its four headquarters buildings with a single network using a medium that could withstand environmental conditions outdoors and ensure reliability between remote locations over long distances. In addition, the network had to allow the various control products and appliances among the four buildings to communicate with each other and to accommodate additional components and/or buildings as the company grew. To meet REI’s needs, the contractor turned to CBL Systems Corp. of Hopkinton to provide the Fiber Optic LonWorks Routers for the project, because the routers make fiber simple to install and integrate with any LonWorks system.
CBL Systems provides the only complete EIA/ANSI 709.4 fiber-based solutions for LonWorks distributed sensing and control technology. Fiber optics gives the REI campus an intrinsically safe and highly reliable networking medium that is virtually immune to the effects of electro-magnetic interference, moisture, lightning, high voltages, chemicals and other ground potential or environmental factors.
The fiber optic network at the REI campus is configured in a ring redundant format with CBL routers linking the four buildings into a loop that enables constant two-way communication between all points. Nearly 300 sensing and control nodes operate on the network, which is easily expandable for more buildings, more control functions, or both. When configured in a ring, a fiber optic network using CBL products creates two redundant information paths between each node. The CBL routers contain patented circuitry that enables them to receive and transmit messages bi-directionally and in real-time to the next node on a subnet so that continuous communications can be maintained even in the event of a break in the system.
Until recently, configuring a building with fiber optics was viewed as difficult and more costly than using traditional copper wiring, and many systems integrators tended to shy away from it. But just as the personal computer led to an explosion in computer technology and eventually made desktop computing universally affordable, the development of interoperable, open-control networks and flexible, plug-and-play fiber optic networking has made fiber optic-based control networks affordable and easier to install than ever. Advances in the use of fiber in the telecommunications industry has led to simple, low-cost, field-installable cables, connectors and system components that are as easy and cost-effective to use as twisted pair.
