ATLANTA - Five addenda to the American Society of Heating, Refrigerating and Air-Conditioning Engineers' (ASHRAE's) BACnet standard were recommended for public review at the Society's 2006 Winter Meeting.

ANSI/ASHRAE Standard 135-2004, "BACnet® - A Data Communication Protocol for Building Automation and Control Networks," allows building equipment and systems manufactured by different companies to work together.

The proposed addenda, c, d, e, f, and g, are expected to be released for public comment in March.

In other news, BACnet committee chair Bill Swan announced the formation of the wireless BACnet working group.

"There is considerable interest in wireless applications for building automation," he said. "This group will work out the details of BACnet wireless communications."

A new means for securing network communications would be provided through proposed addendum g. Over four years in development, the proposed addendum draws on advances in encryption and authentication technologies.

"This system can be scaled way up for high security or way down for simplicity," said Dave Robin, network security working group leader. "It provides two levels of access, with a general key for reading and writing basis system data, and application-specific keys plus authentication for connecting to critical systems including access control (security) and fire safety."

Proposed addendum f includes the first of a series of new BACnet access control objects in development in the life safety and security working group. The access door object represents the physical characteristics of an access-controlled door and its associated physical hardware and devices, including door contacts, door locks, and card readers.

The BACnet Web services proposed in addendum c have been revised by the XML working group and recommended for second public review following the resolution of 53 comments received from first public review. BACnet Web services provide access to data in BACnet systems using standard PC desktop software vs. specialized drivers. They also are proposed for the communications between energy utilities and BACnet systems for demand limiting and real-time pricing.

The load control object proposed in addendum e has been recommended for second public review. It provides a standardized means for external control over load shedding and is the first of several proposals from the utilities integration working group, working to connect the energy utilities with building automation systems.

The BACnet committee continues its range of work on items such as defining a standard mechanism for presenting application devices such as VFDs and VAV controllers; accommodating and adopting new IP technologies; advanced lighting control support; and extending conformance testing as new capabilities are added to BACnet.

Publication date: 02/20/2006