There has been a lot going on in the world of building automation systems (BAS) in the last decade. Prior to that time, proprietary BAS were the norm. In these types of systems, the manufacturer controlled every internal aspect of the system, the components could only be purchased from the original manufacturer, and the system could not easily be linked to any other manufacturer’s system.
Today, most manufacturers are emphasizing the need for “open” systems that use communication protocols such as BACnet®, LonWorks®, and ModBus. These manufacturers still support their older proprietary systems, but as a whole, they’re working to move their customers into the world of open protocol systems.