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On Speaking Terms
Although the concept of interoperability has been in the planning stages for more than 15 years, and thousands of interoperable systems are currently installed and operating, the industry is really still in its infancy. Successful installations are common, but so are ones that are at least somewhat disappointing. Great advances have been made, but not all systems are truly interoperable. And while things are moving towards full interoperability, care must still be used when designing and developing an interoperable system.
Perhaps the most significant difference between successful interoperable building automation systems and those that are merely satisfactory is the level of planning that goes into the system before the installation process. On successful projects, facility executives understand the capabilities and limitations of the system before it is installed. Steps are taken to ensure that the components installed in the facility are truly interoperable. And facility executives understand and avoid the most common pitfalls that plague less successful systems.
Understanding the Benefits
One of the most common problems with interoperable system installations is unrealistic expectations. Interoperable systems offer significant benefits, but they cannot do everything, and they do require a significant level of ongoing support from the facility staff if these benefits are to be realized.
One of the most significant benefits of interoperability is the single user interface. With a single user interface, personnel need to learn, operate, and maintain only a single system instead of multiple systems, reducing both the learning curve for the system and maintenance costs.
Interoperability also breaks the grip that vendors have on the owner when proprietary systems are installed. When a proprietary system is used, owners can become locked into a single manufacturer for all future system upgrades and expansions. Interoperability introduces competition for both components and support. Competition in turn allows owners to select components on the basis of both price and capabilities. This means the system can be optimized for the facility.
Getting away from proprietary systems and their related expansion costs is particularly important given the constant state of change in most facilities today. With seemingly never-ending moves, and changes in occupant support requirements, facility executives are struggling to keep up. With interoperable systems, changes to the building automation systems are significantly easier and less costly to implement.
Interoperable systems give facility executives a powerful tool for improving energy efficiency. The combination of all monitoring and control functions into a single system allows better scheduling of equipment operation as well as implementation of more complex control strategies. With growing use of real-time energy pricing, managers can use utility metering data on a real-time basis to direct their energy efforts.
While saving energy, reducing operating costs, and improving flexibility are important factors, one of the real benefits of interoperability often goes overlooked: added value. If a building automation system can improve occupant comfort and convenience while reducing operating costs, it will allow the facility to become more competitive in the marketplace. That alone is sufficient reason to consider interoperable systems.
Getting to Interoperability
Interoperability is not something that can be purchased off-the-shelf or out of a box. One size does not fit all. One of the worst mistakes is to select a particular system and force fit it onto the organization. Getting to interoperability is a process that must be undertaken very carefully.
Start with an evaluation of the facility and its operations. Identify the systems that need to be integrated and why. Clearly spell out the goals for the system. If needs and objectives are identified early in the process, it will be easier to evaluate system options when they are submitted by vendors.
Involve the information technology staff. Most buildings today are wired for networks that are under the control of the IT department. Get them involved early in the evaluation of options so that the new system will be able to use the existing network.
Selecting a Protocol
Several routes can be followed to interoperability. A variety of standard and open protocol options have been developed for building automation systems. These protocols serve as tools to allow systems and components from different manufacturers to communicate. These protocols are available to any building automation system, subsystem and component manufacturers. It is the use of these protocols that has made interoperability possible. While each protocol provides a route to interoperability, it is important to recognize that they are different and generally incompatible routes.
The most widely used protocols today include BACnet, LonMark, and Modbus. All three protocols have very detailed and specific rules that must be followed. All require detailed testing and certification to ensure that components adhere to standards set by the protocol.
Each protocol has its own merits and limitations. Determining which is best for a particular application will require an evaluation of the effectiveness of each type of system in relationship to the needs of the facility, including growth, expansion, changes, the abilities of the maintenance staff, the quality and cost of service contracts, and the initial and life-cycle system costs. If the facility lacks in-house expertise for this evaluation, seek help from a qualified, independent firm.
A detailed set of specifications will need to be developed to support the project implementation. Those specifications will need to identify the protocol to be followed, what systems and components will be connected to the system, who has the responsibility to integrate equipment from different suppliers, what documentation is required, and the commissioning process to be followed before the project is accepted.
When soliciting bids, fully research the system installers. Determine their level of experience with interoperable systems, including how many systems they have installed, the level of interoperability achieved in those systems, and how satisfied the owners of those systems are.
Avoiding the Pitfalls
Interoperability is a rapidly evolving field. As a result, not all systems being sold as interoperable are fully interoperable. Proprietary components and systems still exist within interoperable systems. Therefore it is important to thoroughly investigate any system being evaluated.
As with any building system, overall system performance will be determined by the weakest link in the system. This is particularly important when operating in a multivendor environment. One vendor’s lack of performance can hurt the entire system.
When the building was operated by independent systems, the impact of a failure of a single system was generally limited to that system. With interoperability, certain failures can theoretically result in the entire system shutting down. At a minimum, this would result in the loss of data. More importantly, it can compromise the operation of building life safety systems. Although such a complete shutdown is unlikely, the system design should include redundancy for protection of the facility and its occupants. Procedures must be in place to regularly and automatically backup data.
Finally, don’t fall victim to the idea that interoperability is not ready for prime time. Interoperability is here and is being used successfully in both new construction and renovation projects.
James Piper, PhD, PE, is a writer and consultant who has more than 25 years of experience in facilities management. He is a contributing editor for Building Operating Management.