BACnet - Building Automation and Control Network - was developed by the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) and is now both an ANSI and ISO standard. The standard continues to be maintained by ASHRAE's SSPC-135 committee and enhancements are frequent. The intent of this open standard is to allow building owners the opportunity to pick and choose BACnet-compliant equipment from various vendors. BACnet embraces object modeling where a physical device is characterized by a group of standardized objects. Each object type has a defined list of properties. The value of each property identifies the uniqueness of each object such as the present value of an analog input object. Devices provide services to other devices which can vary based upon the complexity of the device. BACnet devices are classified by their device profile which is based upon the services that the device can offer. Device profiles can range from a simple Smart Sensor (B-SS) to a complex Building Controller (B-BC).
BACnet devices communicate to one another over a network. The more popular networks include the Internet Protocol (BACnet/IP) and the Master-Slave Token-Passing network (BACnet MS/TP). Interconnecting BACnet networks requires BACnet routers while connecting non-compliant BACnet devices to a BACnet network requires a gateway.
The BAS Router is used to route messages between BACnet/IP, BACnet Ethernet and BACnet MS/TP networks. Two versions are available-a DIN-rail mounted unit for fixed installations and a portable unit for commissioning and troubleshooting.