AutomatedBuildings.com
Article - September 2003
[Home Page]

Innovations in Comfort, Efficiency, and Safety Solutions.
Belimo

(Click Message to Learn More)

Protocol war yields to productive peace

Ironically by narrowing the choice of control protocols the industry can now invest more in well understood, and supported systems that are easy to specify, install, integrate and modify. 

Peter Manolescue,
Sales and Marketing Director

securityXML Ltd.

Peter Manolescue is combining a career of practical business and commercial knowledge with IT experience to help the security industry take full advantage of the latest computer technology.


Business trips are a real hassle: strange airport, strange town and worst of all, strange rental car. You know the drill; nothing is where it is on your car. The indicator stalk is the other side of the steering wheel so you are forever flashing your headlights instead of indicating a turn. The petrol filler cap is on the wrong side which is a real pain when filling up and the radio has a mind of its own; serving only rap music if your preference is classical and vice-versa. You would have thought manufacturers could have worked out some sort of standard by now.

"The Automator"
Articles
Interviews
Releases
New Products
Reviews
Forums
Sponsors
Archives
Past Issues
AutomatedBuildings.com

Securing Buildings News

Some business sectors have managed to get further than the automobile industry. The IT world has the de-facto Wintel (Windows plus Intel) standard in which (assuming you don't have an Apple, Unix or Linux computer) you can swap files between different systems without a problem. This standard came about by pure commercial pressure. Whether or not you agree that a few companies should impose their technology on an industry, there are plenty of examples, which show it to be vital to industry and market expansion. VCRs, electricity supply, telephones and railways are examples of innovations, which did not really begin to expand until one technical standard rose to dominance.

Most markets follow the same general path. Initially, the market is fragmented as suppliers see the opportunities in different ways. Engineers design products independently according to their own experience and prejudice. As the market grows and customers require products from different companies to inter-operate, many ad-hoc schemes to link and integrate these systems are developed. Through a process of economic natural selection and customer pressure, the number of technologies is whittled down to a few. Finally, a dominant standard is imposed often by the largest supplying company in the market (as Microsoft has done in PCs) or by a powerful buyer (such as the US Department of Defense did with TCP/IP). It is not obvious at the outset, which technology will be triumphant but invariably one is.

From a technical point of view the Intelligent Building market can be seen as having passed the initial stage and is now consolidating. Only five years ago there were plenty of contenders for the standard building control protocol. As well as proprietary offerings, there were many strong contenders such as Profibus, N2, Modbus, FND, and CAB. This list was whittled down until it seemed there were only two protocols with a chance: BACnet and LonWorks. Until recently, the proponents of each seemed to spend as much time attacking the other as promoting themselves. Now peace has broken out largely thanks to some new kids on the block: Niagara and XML(eXtensible Markup Language). At the recent BuilConn convention in Dallas it became apparent that there may be a place for all of these technologies. If one of them finally does become predominant then the process will be gradual but will not hinder the larger movement: the realization of the Intelligent Building.

So are these protocols competitive or complementary? Well confusingly, a bit of both (whoever said life would be simple?). What became clear at BuilConn is that each has a role to play and because each is developing quickly, choice, economy and span of control is increasing rapidly for building owners, operators and occupants.

Control Solutions, Inc LonWorks, invented, developed and promoted by the Echelon corporation can be viewed as building automation for plumbers; the output of one device is fed into the input of another using a common data pipe. This is often the LonBus but it can be power line, wireless or a number of others. So controls bought from one company can be hooked up to the machinery from another fairly easily. LonWorks does not depend on a central computer but it does require the use of devices with the Echelon Neuron chip or its equivalent. LonWorks systems can start small and grow incrementally to powerful multi-site control networks by sending the messages over LANs and WANs.

If LonWorks was designed by a plumber then BACnet was designed by a committee of computer geeks. The basis of BACnet is the abstraction of the real world into a number of software objects which when assembled correctly simulate the behaviour of a real-world item like a boiler or a fan. Describing one of these devices in BACnet is a bit like describing a car by its components (take 1 engine, add 4 wheels, connect together with a transmission train, mount everything on a sprung steel frame etc, etc). To get the most out of BACnet system, a central control computer is almost essential. BACnet took 8 years of committee work to develop and during that time the preferred target networking technology, ARCnet, got trounced by TCP/IP and Ethernet. So BACnet/IP was developed and is now the most common variant found.

Although there is considerable overlap, the general feeling is that LonWorks is superior at the field bus level to connect simple devices to form more complex systems. BACnet begins to come into its own at a higher level (the automation level) where its schedules and logic can automate operations between complex sub-systems. At the highest level (known as the management level) one usually finds bespoke software to implement the man/machine interface. Today this is usually some sort of graphical user interface (GUI) with a database which represent the facilities and systems being controlled. This is where Niagara and XML are making their mark.

Niagara is a Java based framework which allows a number of 'plug-ins'. These correspond to incompatible subsystems that can then be integrated together under Niagara. LonWorks and BACnet do not directly interact but both can be operated and integrated using Niagara. Different databases may also be logically connected. For example, events from many different incompatible systems can all be logged in a preferred database format and controlled from one graphical screen. In this way users can continue to exploit legacy systems without costly rip-out whilst ordering best of breed new equipment from any source without worrying about interoperability. Niagara can almost be viewed as universal 'adapter' for building automation systems.

Niagara was designed specifically for the building systems market. XML however is the latest hot technology from IT. Integrating computer systems has historically been a nightmare. In some cases, it has been so difficult that company mergers have been abandoned due to extreme incompatibility between computer systems. Many companies have old 'legacy' applications that have hundreds of man-years of development tied up in them. Rewriting them in more modern languages is often not an option due to cost. Yet a large amount of value is locked in the old system. In addition there is an increasing need for company systems to integrate closer with those from suppliers, customers and agencies. To achieve this required a radical new approach: XML/Web Services. Because of the investments already made (Microsoft alone has spent over $9bn on XML technology) this leverages the immense power of the Internet and its technologies to achieve integration and interoperability. Web Services use XML extensively. As a result a large number of powerful software tools are available. These can be used to integrate disparate building systems.

Reliable Controls These developments come at a fortunate moment as energy use and changing work practices put new pressures on building services. In the US there is a developing energy crisis, which will come to Europe shortly. At first sight energy should not be a problem in America. However, recent sharp increases in energy costs, added to distribution bottlenecks, have prompted change. Instead of running lights and chillers flat-out companies are looking for ways to economise. Facilities represent a large part of the fixed costs of most firms. With static sales and squeezed margins companies are looking at ways to use space more efficiently. Combine this with a requirement for more agreeable work places plus an increased level of security and the need for integrated, intelligent buildings where people can work efficiently and safely becomes imperative.

Studies repeatedly show that employees are positively motivated by an environment where they can control their personal space to a high degree. Heat, light, humidity and ambient noise are among many factors that influence worker output. Only an intelligent building with flexible, networked systems controlled by powerful software can provide individual employee comfort whilst controlling corporate expenses and security.

So this then is the challenge to which the latest developments in building systems are responding: how to make facilities flexible both industrially and economically. Ironically by narrowing the choice of control protocols the industry can now invest more in well understood, and supported systems that are easy to specify, install, integrate and modify. By investing in technology that is open and adaptable owners, operators and occupiers will reap the benefit for many years to come, knowing that they can cope with whatever an uncertain world will throw at them.


Reliable Controls
[Click Banner To Learn More]

[Home Page]  [The Automator]  [About]  [Subscribe ]  [Contact Us]

Events

Want Ads

Our Sponsors

Resources