Upgrading LONworks

By Eli Kaberon and Bettina Chang, Editorial Interns August 1, 2009

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As building automation becomes more important for energy efficiency, convenience, and the bottom line, engineers and building owners demand systems that can incorporate products of varying brands in an open-bid market. LONmark has developed and advanced the LONworks protocol to manage these changing technologies, allowing engineers, owners, and contractors to choose the products that work best, cost less, and communicate with the network.

With constant updates to the existing protocol and development of new "smart" technologies, the standards appear to be advancing as quickly as the technology they integrate.

Smart grid

Plans for an American smart grid have included lofty numbers and goals for some of the nation’s biggest companies, and LONmark is one of them. The National Institute of Standards and Technology brought together LONmark and other private companies to help create the Smart Grid Standards Roadmap and recommend a list of standards that should be included in the development of the nation’s smart grid. In the proposed American smart grid, buildings will have "smart" electric meters that can feed information back to the electrical grid regarding a building’s energy use. The smart grid will know when a substation fails and will be able to redirect power from other sources to avoid outages, as well as intelligently manage power from less consistent sources like wind turbines or solar panels. With its capacity for two-way communications and demand-response devices, LONworks hopes to play a big role in the future smart grid.

"LONworks enables various products to interoperate, and smart grid systems can be shared with other products without having to restructure an entire system," said Ron Bernstein, LONmark’s executive director. Buildings with automation systems such as LONworks should fit more easily into the smart grid and help detect and diagnose the grid’s problems, alert operators to correct inefficiencies, and curtail the nation’s energy use.

Smart kitchens

As an energy-intensive space with active HVAC, plumbing, lighting, and electrical equipment, commercial kitchens stand to benefit from integration. LONmark is working to integrate kitchen equipment and make food preparation rooms energy efficient. According to Bernstein, LONmark is in talks with the U.S. military regarding the integration of kitchens in base commissaries. Additionally, McDonald’s Corp. brought together a joint committee of North American Food Equipment Manufacturers and LONmark representatives to discuss what smart kitchen standards would look like and what functions the kitchen would serve, according to Bernstein.

Smart kitchens can help reduce energy use by automating some functions of HVAC, cooking, and lighting systems. For example, special timers and switches could schedule optimum start and stop times for kitchen appliances that take time to fire up or don’t need to be on during breakfast or dinner. Frying vats would operate at full power only during peak hours, and exhaust hood fans wouldn’t run at full speed unless the grill underneath was in use. The LONworks protocol would not only facilitate more intelligent and energy-saving operations, but also help collect data that documents the performance of the systems and how much energy is being saved.

Functional profiles

Functional profiles are a standard way of defining devices so they can be handled by the LONworks protocol. With these profiles, controllers know whether they are talking to an air conditioner, lighting fixture, or another device. LONmark regularly refines existing functional profiles and creates new profiles to keep up with technology and to meet specifiers’ needs. Because of the national focus on energy efficiency and green buildings, many of the new profiles relate to demand-response functions and energy savings.

For instance, LONmark is developing a profile for an automatic transfer switch, which would allow buildings to choose between internal or external sources of energy. The system also would incorporate a new wind turbine profile. If a building has a wind turbine on-site, it can feed back excess energy to the grid or choose to store the energy and sell it back at peak hours, when it is more profitable for the building owner.

Another new profile in the works is for lighting controllers. Bernstein said LONmark is working with an advisory board of specifiers, engineers, and vendors to determine how indoor lighting (such as high-bay) could be enhanced with smarter, updated standards. He anticipates that the new standards will increase efficiency by integrating lighting with other buildings systems such as HVAC.

However, updating profiles is not as simple as keeping up with the trends. Some important clients and companies, such as the U.S. Army Corp of Engineers, are requesting specific functional profiles. (See "USACE specifies LONworks," page 17.) Engineers typically can tweak pre-set control sequences to make them application-specific, but some want out-of-the-box sequences to include many inputs and outputs, while others prefer simpler profiles.

LON-to-LAN

This year, LONmark issued an update to its LON-to-LAN tunneling protocol, called IP 852.1. Once all network routers are upgraded, the unpacking of information can occur in any router, and not just the configuration server. This revised standard will make the system safer by using Network Address Translation, which would put the IP addresses of each device behind a firewall. It also allows customers to open a larger platform to bring more buildings into the system.

Although some industry experts had not yet heard of this update, they did agree that the accessibility of LON-to-LAN messages has been improving in the past couple of years and could use even more improvement. This tunneling protocol can be an important feature in LONworks because building operators can access the controls without being in the control room or even on-site. However, some building owners prefer not to use up their bandwidth with building operations at all. IP 852.1 is not widely used yet, and whether it will make a large impact in practice is not yet determined.

USACE specifies LONworks

Due to government rules that ban exclusive contracts to proprietary vendors, the U.S. Army Corps of Engineers (USACE) uses LONworks to incorporate an open system of technologies. USACE works with LON profiles, meaning that every device has identical functions, inputs, and outputs while maintaining its unique capabilities. This allows the USACE to specify a network with different devices that can communicate and be controlled with one system.

LONmark provided the USACE with a unique, open-specification profile that was specially designed to handle its needs. Since the network can connect two to 50,000 devices, according to Bernstein, the association was able to integrate the detailed requests of the Corps to its existing profile specifications. These specs, along with the specs for other high-profile LONworks installations, are available on the LONmark Web site ( www.lonmark.org ) for specifiers looking to control similar building systems.