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At this moment, it seems there are many more opportunities available in upgrades and retrofits instead of new construction. For the purpose of a discussion, let’s assume that I own an office building and I would like to integrate the various systems that control the infrastructure. I’m convinced that action would save everyone money on energy costs and improve the function and flexibility of systems, such as fire alarms; heating, ventilating and air conditioning (HVAC); lighting; security; surveillance; and access control. How do I go about getting started?
It makes sense that efficiently coordinating building systems has a long list of advantages: Save on energy costs by optimizing control of lighting and HVAC. Make the building safer by integrating fire alarms with smoke and elevator controls. Make it more secure by integrating access control with video surveillance, etc. This all sounds great, but the devil is in the details.
What’s next?
Next, I would decide which systems to integrate and how. Not being an expert, I would want to hire an expert, but someone who is not necessarily committed to selling a particular company’s products. I would discuss the various possibilities and have my consultant draw up a performance specification to show to vendors. It would be best to find a design/build electrical contractor with expertise in building systems.
Connectivity as an asset
Common to all systems integration is connectivity—the ability for systems to communicate with each other. So before starting specific systems integration, I need a reliable infrastructure that would enable the building systems to communicate. There are three physical systems that can do this: copper, optical fiber and wireless. It only makes sense to install a connectivity infrastructure that I expect (and can convince my tenants to expect) will support the technology for interconnection as it develops in the future. Infrastructure, if it is done properly, could be used by each tenant for their particular needs without having to make major changes for new systems needs. The potential advantages for new tenants depend on those devilish details. Most important is that the infrastructure I install should be capable of handling the expanding bandwidth requirements that are likely to be the backbone of intelligent building systems for some time to come. James Carlini, president and CEO, Carlini & Associates Inc. has published the following chart, which gives a vivid picture of the growth of connectivity speed in the recent past.
If I am going to install copper or fiber optic cable, it should be a structured system. That means instead of the communication cabling for each device being wired separately, I should install cables to patch panels, so they can be used for different purposes as requirements change. Next, the installed cable should be tested to determine its actual—as opposed to purported—specs. The data should be recorded and saved in an accessible location. In order for this data to be useful, each cable should be labeled at both ends, so that in the future, someone installing equipment at a particular location will know exactly what is available.
Beyond cabling
Carlini suggests that wireless connectivity should be seriously considered for existing buildings, for the obvious reason that this would minimize the need for installing new cabling. He feels that WiMax will grow as a reliable means for transmitting the data to integrate building systems.
Paying for the installation
Why should my tenants pay for upgrading infrastructure to support systems integration? First of all, paying now to install a backbone capable of supporting a variety of systems means minimizing costs in the future. And it also means that they can decide what systems to integrate when the need arises without having to consider the cost of adding infrastructure—the decision can be based on what makes the most sense in terms of function.
Another important factor is that since the 2002 edition of the National Electrical Code, most localities require that abandoned communication cable that is not labeled for future use must be removed from the premises. This can be a major expense that could be avoided by thinking of the communications infrastructure as an asset rather than disposable waste.
Thanks to Frank Bisbee of Communication Planning Corp. for his assistance developing this article.
BROWN is an electrical engineer, technical writer and editor. For many years, he designed high-power electronics systems for industry, research laboratories and government. Reach him at [email protected] or at www.writingengineer.com, an independent professional writing service.