The LonWorks open protocol provides many advantages to all concerned with building systems: planners, owners, system integrators, users and energy managers. It allows system components to be chosen from various manufacturers to achieve best results with the confidence that they will integrate perfectly, and allows compatible devices from any manufacturers to be installed as replacements and during upgrades. But a question often asked is: How can LonWorks be an open protocol when it is controlled by the Echelon Corporation?
When LonWorks was introduced by Echelon in 1990, the protocol was implemented only as hard code, known as LonTalk, in dedicated microprocessors called Neuron Chips. This was good for the initial launch of the system because product development was made simple. Device manufacturers only needed to develop the application and did not have to concern themselves with the communications part of the product.
In 1999 the protocol was published by Echelon and can be downloaded for an administration fee of £30.00. It enables manufacturers to implement the LonTalk stack onto any suitable processor. Loytec, Open System Solutions, Adept, Domologic, and Frauenhofer have all produced implementations of the LonTalk stack which are either embedded on dedicated processors or can be ported to a preferred processor.
Another component required is a transceiver (available from several sources); again, specifications for different transceiver types are available in the same way as the protocol.
The protocol is a European, American and Chinese standard; work is under way to make it a worldwide ISO standard. Links to the standards and more information is available on the LonMark website: www.lonmarkuk.com/html/standards.php
As the protocol and transceiver specifications are public knowledge, the components required to deliver an open system are being manufactured by companies other than Echelon.
The only part of the system still under Echelon’s control is LNS, a common platform that allows different network management tools to work together on the same system. Echelon uses this in LonMaker for Windows, while Newron, for example, supplies NL Facilities. Other developers have their own systems. Since they all use LNS as the underlying database, the tools can be used on the same system at the same time. Product manufacturers can provide LNS plug-ins that allows devices to be interrogated and configured in a user friendly manner, without the need for specialised tools.
Echelon is in competition with other suppliers of open system products: this has been good for the industry as many new, innovative products are available from both Echelon and other manufacturers.
We are now seeing the technology being taken to the next level. Processing power has increased significantly since the Neuron chip was first produced, so the LonTalk stack is being implemented on a wide range of processors, allowing provision of more integrated and energy efficient solutions. In many LON installations the control system links to the corporate network. Control system data can be transmitted automatically to a SQL database, allowing meaningful reports of plant performance and energy consumption to be generated and analysed.
As LonWorks is such a well-established open standard, and such a large number of companies are applying the technology in their products, the long-term future of LonWorks is assured as a building control and automation standard and the means to make significant energy savings.
