By enabling products from different vendors to interact with one another, interoperable building systems based on the BACnet open standard improve building management, increase operational efficiency and flexibility, and hold down service and expansion costs. The power of today’s BACnet-based systems continues to increase as the number of interoperable devices increases.
Although BACnet has its roots in the HVAC industry, the BACnet protocol is being used in an expanding range of product categories. “The BACnet protocol has a wide appeal to the end user and, because of that, the tent is being broadened to be more inclusive of other major building systems,” says Raymond Rae, vice president, Delta Controls. “The development of BACnet has been driven by the marketplace.”
One important trend in the market has been the growing emphasis on integrated systems. Because the standard is continually evolving and being modified, BACnet has kept up with developments in building automation technology.
“In the 10 years since the standard was approved, BACnet has gained a solid foothold in the building automation industry,” says Ronald Zimmer, president and CEO of the Continental Automated Buildings Association. That means a wider range of applications for BACnet-based systems.
BACnet’s popularity developed slowly but steadily outside the HVAC industry. But today, says Roy Kolasa, open solutions market manager for Honeywell, BACnet technology can integrate HVAC, fire/life safety, and security and access control, as well as energy management and enterprise level systems.
Although facilities executives were excited about the benefits of interoperability, they proceeded cautiously in BACnet’s early years. Now, however, many companies are seeing significant growth in BACnet requests and applications, particularly on large projects.
“We have a major North American university that has decided to standardize on BACnet solutions,” says Kolasa. “Testing by BACnet Laboratories is important to them because the manager isn’t looking at a few hundred points. This application eventually could be 30,000 to 40,000 points.”
Interoperable systems are being seen as a competitive advantage for a growing range of products. “For an HVAC drive not to be able to connect to another vendor’s equipment without modification places it at a significant disadvantage,” says Peter Walter, HVAC product marketing manager for ABB. “Interoperable systems allow products and systems from multiple vendors to be used together without modification or development of custom interfaces and tools.”
Some proprietary systems are also interoperable, but these systems require multiple vendors to use a proprietary protocol. This places a burden on those vendors, says Walter. If a vendor’s products and systems are compatible with only one protocol, that company has limited access to the market.
To reach the largest market, a vendor would have to implement multiple proprietary protocols in a single product. “BACnet as an open protocol poses no such obstacle,” says Walter.
It’s not just vendors who experience the drawbacks of proprietary systems; facility executives feel the impact as well. “Installation and operation costs increase, system effectiveness decreases, reliability and maintenance suffer,” Walter says.
The BACnet Testing Laboratory, which provides independent evaluations of different vendors’ products to see if they meet all of BACnet’s requirements, has played an important role in the growing acceptance of the protocol.
Another important factor has been so-called BACnet “Plugfests,” where manufacturers gathered in private sessions to test the interoperable functionality of their products. In those sessions, away from the pressure of job-site installations, vendors could identify functions that were working well, along with issues that needed to be ironed out, says Rae.
As facilities executives choose BACnet for their building automation applications, they are finding that interoperability places more at their fingertips than they initially imagined. For instance, at a Canadian university, once the various systems were brought together, the facilities executive discovered that 60 large pumps could be shut down. “They were over-engineered and didn’t need to be running,” says Kolasa.
Once approached with some trepidation, BACnet is now a mainstream selection for a growing number of facilities executives. “Particularly on larger projects, there clearly is a trend by building owners to have single-seat control of their building,” says Pete Baselici, senior product line manager for lighting control panel products at Watt Stopper.
Integrating lighting controls with the building’s automation system requires more sophisticated lighting controls, he says. “You cannot just switch lights on and off and meet energy code requirements.”
BACnet provides the level of sophistication necessary, says Baselici. The concept of interoperability has “turned the corner on acceptance,” he says. “It’s no longer out of the ordinary. It’s become mainstream business for us. The obstacles that remain are those systems integrators who have never done it before. For them, there is a learning curve, but BACnet makes it pretty easy. We continue to work with systems integrators, trying to streamline that process for them.”
The desire to increase collaboration within the BACnet community recently led the BACnet Manufacturers Association and the BACnet Interest Group — North America to merge into BACnet International. “We believe the new organization represents a coming together of many parties into a cohesive group,” says Ben Dorsey, vice president of communications for KMC Controls and marketing committee chair of BACnet International. The organization’s new Web site contains BACnet news and product information. The new organization also is transitioning to a different test facility for its BACnet Testing Laboratory (BTL), the location of which is expected to be announced shortly.
“The continuing solidification of the BACnet standard and a genuine interest to work together to give customers products that truly interoperate is what is driving BACnet’s success,” says Mark Bergman, director, McQuay Controls. “The real value of any automation system in the end is that it works, not only today, but also 10 or 20 years from now.”
Successful technology vendors, such as Microsoft, Intel and Cisco, are constantly refining, upgrading and revising their product lines. Building automation technology also needs the flexibility to grow. But any new technology also needs to work with legacy systems that are not typically replaced every five or fewer years. For example, a building’s chillers often perform for 30 years.
That is why the American Society of Heating, Refrigeration and Air-conditioning Engineers (ASHRAE) remains important in the development of BACnet. ASHRAE spent years developing the open protocol to make sure it delivered what facilities executives wanted — interoperability between systems from different manufacturers. Now, ASHRAE working groups seek to ensure that BACnet continues on the same path, so that facilities executives can choose the best option when shopping for equipment and systems.
Because facilities executives are looking at wireless building systems network possibilities, ASHRAE formed a working group in January to investigate development of a BACnet wireless addendum. There are wireless building network solutions available today, but they are essentially proprietary products.
Facilities executives interested in venturing into wireless building systems networks must decide whether they are willing to be tied to a proprietary vendor for their wireless configurations or if they want to hold out for open wireless networks. “Some facilities executives may be attracted to the benefits of wireless systems, without looking long term,” says Andrew Wilcox, controls business leader for Trane. Wilcox suggests facilities executives demand an interoperable wireless system from the outset.
“Interoperability for wireless products is no less important than interoperability for wired products. All the same reasons apply,” he says.
Chris Hollinger, product manager systems integration at Siemens, says his company is looking at using BACnet Internet Protocol (IP) over a wireless IP network. “We plan to test that configuration,” says Hollinger. “But it’s still fairly early and we want to make sure that direction will work before we start touting it.”
Siemens does offer a proprietary wireless network today, Hollinger says. “But we believe its extremely important to develop a true wireless standard, because many customers will want integration and interoperability.”
The demand for interoperable wireless networks is coming from the customer, according to Jon Williamson, senior product manager at TAC. “People are accustomed to being able to purchase from multiple manufacturers. Just because they are going wireless does not mean that they want to give that option up.”
Williamson sees wireless interoperability developing across two phases. “Phase One is where we are at today,” he explains. “You have a wireless network with one manufacturer, with a router between it and BACnet topologies from other manufacturers. Phase Two is writing wireless networks into the BACnet standard.” When Phase Two is completed, facilities executives could purchase wireless solutions from multiple manufacturers.
John Ruiz, wireless building controls program manager for Johnson Controls, is looking forward to development of a BACnet wireless network standard. “We try to build our products around standards,” he says. “Standards give our customers the ability to expand and interoperate with other building systems.”
One of the reasons there are few applications of wireless networking in buildings is that facilities executives are waiting for standards that will offer them interoperability across various building systems and subsystems. “When the wireless BACnet initiative is complete, I believe we will see more wireless network applications,” says Terry Hoffmann, director of marketing, building automation for Johnson Controls.
Despite the many advances being made, BACnet is not becoming a plug-and-play standard. Nor do the experts anticipate such ease in this robust, sophisticated open standard. Still, it is easier to specify BACnet interoperability, thanks to an online specification builder. “A consulting engineer can use the site to specify a BACnet job by answering a number of questions,” says Dorsey. Developed by Automated Logic for use by the BACnet community.
A series of innovations have helped BACnet become a mainstream choice in integration and interoperability, says Steve Tom, director of technical information at Automated Logic.
For example, BACnet has developed standard device profiles. “The profiles define a standard piece of hardware that multiple vendors can make,” says Tom. “This allows the facilities executive to pretty much know what to expect from the controller.”
Another major accomplishment is BACnet’s annex to Web services, which actually is more than it first appears. “The ASHRAE-defined information model is an IT standard for different computers to share information that is platform-independent,” says Tom. “That means it can work on Linux, Apple, Windows and other operating systems. The Web services addendum is not intended just for BACnet applications. It can be used for any platform and allows BACnet to tie in with any enterprise system as well.”
BACnet Web services is an opportunity for interoperability between utilities, building automation systems, building maintenance and enterprise financial systems, says Scott Holland, director of engineering for systems technology at Johnson Controls. “For example, using Web services, you could track people who have access to your facility. You might notice that John comes in on time and have his office conditioned and ready when he arrives.”
The BACnet addendum for Web services, Addendum C, received many comments, and changes have been incorporated in the new version, which is out for its second public review now, according to Bill Swan, engineering fellow with Alerton/Honeywell. “A lot of people are waiting for this addendum to be released as it has the ability to connect the building automation system to corporate enterprise systems.”
In a marketplace where facilities executives requested more freedom in choosing suppliers for their building systems and subsystems, BACnet offers a viable alternative to being tied to one building automation supplier. That interoperability, driven by customer requests, is propelling BACnet in today’s building automation market.
ASHRAE continues to refine and upgrade BACnet. One example is a development that will give BACnet systems the ability to shed loads on demand. Contained in Addendum E to the standard, the load control object is the first item to come out of BACnet’s utility integration working group. What it represents for facilities executives and energy utilities is the ability for demand shedding and real-time energy pricing.
Addendum F, an access door object, is the first of a series of expected modifications addressing access control issues, from BACnet’s life safety and security working group. That working group is collaborating with security industry associations in producing data models and proposals.
Another example is the structured view option in Addendum D. The structured view option allows workstations to go to a particular device and learn from it how data is organized. “It will give facilities executives an immediate way to find the particular values they are interested in,” says Bill Swan, engineering fellow with Alerton/Honeywell.
In addition, Addendum D allows multiple paths to one data value. Facilities executives will be able to get data on one chiller, for instance, then for all chillers in the complex. They’ll then be able to back up to the actual floor zone temperature setpoint without requiring a specially configured workstation to get that information.
Addendum G is a network security proposal that offers a means for securing BACnet over unsecured avenues. Encryption guards against eavesdropping and authenticates sources of messages.
Finally, BACnet’s Addendum B also is undergoing some changes. One of them is an event log object to allow a standard way to record alarms.
Two major players in the BACnet arena have joined forces. In January, the BACnet Manufacturers Association (BMA) and the BACnet Interest Group of North America (BIG-NA) voted to combine into a single organization named BACnet International. “It’s a maturing of the industry,” says Andy McMillan, president and CEO of Teletrol International and president of the new organization. “In the early days, the user and supplier communities were separate and sometimes had separate motivations. We recognized that there is a common interest in growing the BACnet community.”
With members from across the industry — including facilities executives, manufacturers, system integrators and consultants — BACnet International will smooth communication among groups interested in BACnet and provide a structured forum for discussions.
The organization offers different levels of membership for different groups, says Ben Dorsey vice president of communications for KMC Controls and marketing committee chair for BACnet International. “We’ve even created a membership for BACnet sites, facilities whose owners wish to receive recognition for their integration or interoperability.”
A steering committee that draws from across the range of BACnet constituencies has been formed to set the agenda for the organization. Among the initiatives that will be supported by the new organization are testing, education, international liaison and marketing.
“I spent a number of years in open systems related to manufacturing automation,” says McMillan. “When various groups in an industry came together, the results were outstanding. I expect BACnet International to have the same impact on this community.”