BACnet

BACnet defines how building devices describe their data as standard objects (analog inputs, binary outputs, schedules, trend logs, alarms) and exchange it. It runs over several network types; BACnet/IP over Ethernet networks and BACnet MS/TP over RS-485 wiring are the most common. Conformance is commonly demonstrated through BACnet Testing Laboratories (BTL) listing.

Supporting BACnet makes a product integrable into most commercial building systems without custom drivers, although the quality of an integration still depends on clearly named, scaled and documented points.

Where it bites: MS/TP networks are sensitive to wiring, addressing and baud-rate mistakes; classic BACnet has weak security, which BACnet Secure Connect (BACnet/SC) addresses; and project specifications often require particular device profiles or BTL listing.