You want a cost-effective building that works. The building automation system (BAS) you choose is integral to how your building performs. A BAS must respond to changing requirements for energy efficiency, indoor air quality, and space comfort. It must also respond to operational and structural changes such as remodeling or retrofit. Effectively integrating all building services into a single BAS is a complicated and ongoing task, and although the industry is making progress, some challenges remain.
One of those challenges is standardization of the communication protocol that enables the BAS to coordinate and control sophisticated subsystems and mechanical equipment. Open, standard protocols, such as BACnet® and LonTalk®, are internationally recognized standards, or languages, that have been developed and are maintained by industry consortiums. Proprietary protocols are developed by an individual manufacturer and are modified by that manufacturer for its specific communication requirements. Embracing open, standard protocols can simplify building integration and ultimately reduce the cost to own, operate, and maintain a building for years to come. Here’s why:
Open, standard protocols don’t require translating. An automation system integrates several building sub-systems. Many of these intelligent building services have their own controls for managing equipment functions. If any of these equipment controls do not speak the language of the automation system, then gateways or “translators” are required, adding equipment expense, as well as programming and commissioning time, and cost. It also adds to the chances of a communication failure.
Open, standard protocols support equipment over its useful life. HVAC equipment can last from 10 to over 30 years. BAS communications and information technology evolve every three to five years. Somehow these development cycles must work in sync. A BAS must be able to support equipment throughout its useful life (i.e., the BAS must be backward compatible).
When a BAS is upgraded to incorporate technology advances or to support new equipment, it must still be able to support existing communicating systems and equipment already in place. Many BAS are not backward compatible because they use a closed, proprietary protocol. The result is that the upgraded BAS may not readily communicate with your building’s existing equipment, creating the need for costly gateways and re-commissioning through multiple BAS upgrades. Worst-case is that you may have to replace equipment that cannot be supported through its useful life.
To achieve standardization – and a building that simply works – the focus must be on the lowest common denominator: the communications protocol. Require that both your BAS provider and equipment manufacturers use open, standard protocols – and that all integrated components strictly comply with the standard objects and services prescribed by those protocols.
Mark Bergman is director of controls at McQuay International (www.mcquay.com), Minneapolis, (800) 432-1342.