Use of the LonWorks protocol in the HVAC controls industry is declining, but not as fast as commonly thought, Omar Talpur, security and building-technologies analyst for global information company IHS, says.
“Over the past two decades, manufacturers in the HVAC controls market have been moving to open protocols, as end users have pushed for a marketplace where they are not trapped with a single manufacturer for the life of a building,” Talpur explains in a research note. “When this movement first started, BACnet and LonWorks fought to become the industry standard, and each offered the promise of truly open systems. Over time, industry leaders began to use the free BACnet protocol more frequently at the management level, especially in the United States, since LonWorks has a fee for each instance the protocol is used.”
Talpur says definition of a HVAC controls system based on the protocol present at the management level is not an accurate representation of protocol use, as integrators typically use multiple protocols within a single system.
“What an integrator defines as a BACnet system could have a mixture of Modbus and LonWorks at the field level,” Talpur says.
IHS found LonWorks is the primary protocol for 21.2 percent of controllers worldwide.
“While that rate is expected to decrease over the coming years as BACnet becomes even more ubiquitous, IHS has forecast the decline for Lonworks to be slow, with 19.4 percent still using the protocol in 2018,” Talpur says.
The bottom line, according to Talpur: “Due to the slow-moving nature of HVAC control products, manufacturers and integrators need to be careful to not underestimate the presence of LonWorks in the marketplace or the complexity of current systems. Doing so will further contribute to a lack of understanding about HVAC controls from the end user’s point of view and inhibit integrators from correctly maintaining and fixing systems.”