In the last two decades, bas has literally come out of the closet. No longer hiding under a perceived cloak of secrecy, numerous engineers and manufacturers now emphasize the need for open systems, which utilize communication protocols such as BACnet, LonWorks, and ModBus. As such, proprietary systems seem to have fallen from favor.

Many manufacturers that previously offered proprietary bas now espouse the benefits of open protocol systems, saying for example, that open protocols allow endusers to buy from various sources, and they allow various systems to be tied together to perform seamlessly. Other benefits, they note, include increased speed, power, and flexibility.

But not everyone agrees that the open protocol systems are performing as well as advertised. Some engineers and manufacturers say that open systems are much more complex to design and install than proprietary systems. That complexity, they note, makes it almost impossible for an enduser to make any changes to a system without hiring a programmer. People in this camp argue that endusers often prefer proprietary systems because they are less costly and easier to use and service.

What is true is that the term "proprietary" has taken on a negative connotation and "open" has taken on a positive connotation. This polarization, one manufacturer notes, makes it easy to lose sight of what really matters most: the best interest of the building owner.

A Proper Definition

It is quite difficult to come up with exact definitions for an open system and a proprietary system. In fact, in one chat room on the Internet, a controls engineer said it would be easier to achieve world peace than it would be to come up with a good definition of either type of system. Even the manufacturers don't always agree on what constitutes an open system or a proprietary system.

Chris Hollinger, SBT product manager, Siemens Building Technologies (Buffalo Grove, IL) stated that virtually every bas could be classified as proprietary, because "Vendors who employ a bas have closely guarded proprietary components of their system, no matter what communications protocol is employed. If this were not true, then there would be no protection of intellectual capital, which provides the basis of a competitive business environment."

Mashuri Warren, P.E. and Paul Chapman, ASI Controls (San Ramon, CA) agree, noting that "Most communications over BACnet networks are uniquely proprietary extensions built on top of BACnet. This custom layer built as an extension over the basic interoperability layer is necessary to accomplish anything beyond the basics. The real problem is that no two vendors implement the same custom extensions, so you are right back to where you started from, totally proprietary solutions, disguised as 'open' under the umbrella of BACnet."

On the other hand, modern proprietary systems often communicate to other manufacturers' systems through open protocols, so Brady Nations, senior marketing manager for building automation, Johnson Controls (Phoenix) said, "Today in the commercial building automation industry, I don't think there's a proprietary system available from anybody."

Some state that a truly proprietary bas is one in which the manufacturer controls every internal aspect of the system, the components can only be purchased from the original manufacturer, and the system cannot easily be linked to any other manufacturer's system. It is true that this was the theory used in bas not that long ago, and there are many of these types of systems still in place. While manufacturers often still support these legacy systems, they're usually not looking to advance these systems any further.

But a proprietary bas today means something a little different to most people. Usually, it means a system utilizing a company's proprietary protocol but that system can typically be linked, through gateways, routers, or portals, to other manufacturers' systems that may utilize BACnet, LonTalk, or another communication protocol.

Rick Focke, director of marketing, Andover Controls (Andover, MA) states that there is a tendency to lump systems into two camps: open, meaning pure BACnet or Lon, and closed/proprietary, meaning non-BACnet or non-Lon. "The reality is somewhere in the middle; it is not black and white. There are many more choices besides BACnet and Lon. Protocols become de facto open standards because they are simple, easy to implement, and end up being used widely based on their inherent benefits. I'm not quite sure that Lon or BACnet have exceeded these criteria yet."

Indeed, Andover's current bas, "Continuum," is a hybrid system, which includes both proprietary and open protocols. The company also still supports its proprietary RS-485 fieldbus called "Infinet," while at the same time providing support for BACnet and Lon devices. "We also support an extensive library of third-party interfaces, which are normally based on proprietary protocols; however, many of these protocols can be considered standards in their own right. This flexible mix enables us to tailor a solution for each of our customers," adds Focke.

Many other manufacturers offer a similar hybrid arrangement, with their bas utilizing both proprietary and open protocols. As Randy Amborn, senior marketing specialist at Trane (St. Paul, MN) noted, there may be a better way to look at proprietary and open systems. "Consider proprietary and open as the ends of a spectrum describing the relative ease of integrating to other components and systems. This enables an objective comparison of the extremes, and a way to see a middle ground that may best address the pragmatic needs of buildings." (Table 1)

Proprietary Benefits

Carrier is one manufacturer that definitely considers its system to be proprietary. "Any commercial communicating product that we have speaks Carrier Comfort Network (CCN). That's our protocol," says Mark Tozzi, controls business manager for North American commercial operations, Carrier (Syracuse, NY). "We do support BACnet, and in the near future we will be supporting Lon and ModBus - not from a manufacturing standpoint but from a portal standpoint. We also support ASCII. But we manufacture controls in CCN."

As Tozzi notes, Carrier's theory is that there is no need to choose one protocol over another. Instead, the company has created a proprietary protocol that can connect - via portals - to any other communicating protocols that might be required. "The Internet is where everyone is going in the future anyway, so why choose one path or another?" asks Tozzi.

Many think that Carrier's bas "ComfortWORKS" only controls a building's hvac systems, but that's not correct. The software gives facility managers total building control, according to the company, including the ability to monitor and manage multiple building systems, such as hvac, lighting, and energy use.

The reason why customers like the Carrier proprietary system, notes Tozzi, is that Lon and BACnet integration isn't as easy as some people think. "It has gotten a lot better, and it's becoming even better. Eventually it may become seamless, but that may be past its lifetime. What customers are typically looking for still is simplicity and commonality for the way they do things."

He adds that another benefit is that many companies like to buy from one manufacturer, because it makes life easier. "Some of our larger customers with multibuilding sites don't want open protocol at all. Besides the commonality, the simplicity, and the serviceability, there's also a cost advantage too." That's because with one protocol used in all the buildings, it's only necessary to have one common set of tools in inventory.

Another reason why customers like proprietary systems, says Tozzi, is that there aren't too many computer science engineers and electrical engineers being employed as building maintenance people. "Most manufacturers aren't experts in anybody else's system, so we're going to expect people in the field who weren't involved in the design and engineering of these products to be experts in all of them? One of the things we've always prided ourselves on with our proprietary network is that it's very simple to manipulate."

There are other manufacturers who do acknowledge the benefits of proprietary systems as well. Mark Rehwald, marketing manager, Staefa Control System Brand, Siemens Building Technologies (Buffalo Grove, IL) notes proprietary protocol systems are designed as systems, not just communication protocols. "Therefore, the benefit is that all of the pieces are designed fit together as a system. Most open protocol systems require a systems integrator to put the network together and potentially a different supplier to provide the controllers and hvac control applications."

Cost is another consideration, said Ralph Box, product executive, Invensys Energy Solutions (Loves Park, IL). "Proprietary systems are usually less expensive to manufacture and support. Due to the complexities interoperability brings to the market, the engineering and installation expense is usually less on a proprietary system. Also, proprietary systems can have faster response times because they are 'tuned' as such."

Steve Ferree, vice president of marketing, FieldServer Technologies (Milpitas, CA) agrees, stating that many device manufacturers have made devices with their proprietary protocol for decades and their manufacturers and technical support are very familiar with the protocol.

"The cost to change to BACnet or LonWorks might be prohibitive considering the relatively low number of sales they might have lost due to the lack of the open protocol. In addition, the open protocol might not currently have all of the data types necessary for a specific product. Remember that it was relatively recently that BACnet added in the life safety data types that better meet the needs of the fire alarm panels," he added.

Support Never Wavers

Many manufacturers are working to move clients toward open systems, but the good news for existing customers with proprietary systems is that the manufacturers aren't about to abandon them. "Our primary use for proprietary protocols is to support our large installed base of customers. It's difficult to justify a payback for replacing a device with an 'open' device that performs the same function. Our strategy has been to use our bas as a way of bridging the old with the new [the proprietary with the open]," stated Simon James, marketing leader - building automation, Honeywell Automation and Control Solutions Service (Freeport, IL).

While Honeywell still manufactures proprietary bas to support its existing installed base of customers, its method with new customers or new installations is to use an open systems approach. "Our premier building automation system is Honeywell "Enterprise Buildings Integrator" (EBI). The product supports our proprietary installed base as well as the open protocols LonWorks and BACnet," said James.

Alerton also continues to produce and support its proprietary product line called "IBEX." "A certain portion of the market is not concerned with open systems," said Clair Jenkins, president, Alerton (Redmond, WA). "[In addition], some people prefer to only have one manufacturer of a product. Other reasons may be for system simplicity or cost savings, depending upon the nature of their system or the offerings of various manufacturers."

Andy McMillan, president and ceo, Teletrol (Manchester, NH) stated that Teletrol continues to support its "ValuTRAC" modular I/O system that uses a proprietary protocol to communicate with its "Integrator" series of controllers. "Instant transition from proprietary solutions to open systems is not practical for either suppliers or users. It takes time for the industry to evolve, because product lines have to be filled out, consultants and integrators need to become familiar with new ways of specifying systems, users have to be trained, etc. Therefore, existing proprietary systems will be around for some time to come."

It appears that a strong base of customers using proprietary systems will continue for many years, which isn't necessarily good news to bas manufacturers who see no need to continue promoting proprietary products.

Their points of view will be discussed in the second part of this article, which will appear in the October issue of Engineered Systems. ES

Editor's Note: Some images associated with this article do not transfer to the Internet. To review the figures, please refer to the print version.

Maybe the Type of System Doesn't Matter

It seems that it may not matter whether a bas is open or closed, according to one study. John House and George Kelly of the Building and Fire Research Laboratory at the National Institute of Standards and Technology (NIST) (Gaithersburg, MD) state in their 2000 publication, An Overview of Building Diagnostics:

"Modern buildings are being designed with increasingly sophisticated energy management and control systems (EMCS) that have seemingly limitless capabilities for monitoring and controlling the conditions in buildings. Nonetheless, building heating, ventilating and air-conditioning equipment routinely fails to satisfy performance expectations envisioned at design.

"Furthermore, such failures often go unnoticed for extended periods of time. How does this happen? There are a number of explanations. First, hvac equipment is typically instrumented with the minimum number of sensors sufficient to implement basic local-loop and supervisory control strategies. Lack of sensor information is a significant barrier to assessing the operation of the equipment.

A second explanation is that the data that is collected overwhelms building operators because there is little effort to consolidate the information into a clear and coherent picture of equipment status. Trend data from today's EMCS are useful, but only when analyzed by a human, and this is not a cost-effective way to continuously monitor system operation.

"A third explanation is that building operators may overlook symptoms of a failure because they may not fully understand the control strategies implemented. A related explanation is that lack of understanding of sophisticated control strategies leads to manual overrides that may temporarily alleviate a problem, but may lead to unintended and undetected operating problems in the future. Undoubtedly other explanations exist; however, there is little argument that there is vast room for improvement in the way buildings are monitored."

To view the whole study, go to http://fire.nist.gov/bfrlpubs/build00/PDF/b00022.pdf.