BACnet is a standard communication protocol for automatization networks and building management (
Building Automation and Control Networks) developed by the American
ASHRAE consorcium (
American Society of Heating, Refrigerating and Air-conditioning Engineers), see
http://www.bacnet.org. The main goal was to create a protocol, enabling multiple systems integration from diffrent manufacturers, primarily designed for building automatiaztion.
Message transmission by the
BACnet protocol can be done in differnt ways:
- Ethernet: Transfer rate 10MBps or 100MBps, highest performance option.
- ARCNET: Transfer rate 2.5MBps, deterministic network with token-passing protocol.
- RS485: serial link, Master-Slave/Token-Passing protocol type (MS/TP). MS/TP includes one or more Master nodes, cooperating in logical tokeng-passing circuit. Slave nodes can also be included, able to send messages without Master request.
The BACnet protocol for serial link requires very fast communication responses because it is designed for communication between machines on the lowest level. Therefore it is not suitable for communication with supervisory systems of the PROMOTIC SCADA type.
-
LonTalk: Proprietary protocol developed by the
Echelon company. In
BACnet the
LonTalk protocol is used only for data transfer from one device to another. See also:
Communication in LonWorks networks.
The International Organization for Standardization (
ISO) has adopted and standardized the original American standard
ANSI/ASHRAE 135.
The result is the
ISO 16484 standard, which has multiple parts.
Part 5, the
ISO 16484-5, specifically deals with the data communication protocol, which is
BACnet.
Communication by OPC server
For communication of the PROMOTIC application by the
BACnet protocol the
OPC servers delivered by third parties can be used.
For example:
