Communications Protocols

There is an increasing role for information technology in our lives, including building control systems and facility management. All major communications protocols used in building systems (BACnet, Modbus, Lonworks, etc.) now have a version for Internet Protocol (IP) or Transmission Control Protocol (TCP) that allow the BAS protocol to ride on an IT network. We now have building management systems; basically an IT device with a server, IT operating system, IP address, and IT database. Further evidence of the IT infiltration includes international standards for cabling related to building automation systems that are identical to that of IT, BAS controllers using Wi-Fi, and the current focus on data analytics for building system data. This IT infiltration has and will cause disruptions and adjustments between IT and Facility Management organizational roles.

Wireless Infrastructure

The use of wireless networks control systems in buildings has many advantages. By eliminating the need for cable and related conduit the initial costs for deploying system sensors, meters, and control devices are reduced and installation time is shortened. Wireless is the ideal approach for retrofitting existing buildings where the lack of cable pathways is an impediment.

The major difference between the performance of wired and wireless networks is network communication capacity or bandwidth. However, building systems field devices generally do not need much bandwidth and conduct their business at relatively low data rates. Another potential issue with wireless is that some wireless transceivers may use batteries which require regular replacement. The low data rates and the possibility of periodic battery replacements are minor strikes against wireless compared to its flexibility, cost advantages, and reduced installation time. What follows are some of the choices for wireless networks for building control systems as well as some of the building devices that can be deployed wirelessly.

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