AERCO XPC GATEWAY Communications - Manual (Page 76)

GATEWAY COMMUNICATIONS MANUAL
76
SECTION 8 BACNET
BACnet, which stands for Building Automation and Controls network, is a protocol developed by
ASHRAE. BACnet was developed as a response to industry concerns about increased networking of
BAS components using proprietary communications methods. In the past, these proprietary
communications severely limited the building owners' choices for system expansion, upgrade, and
replacement. Every major controls vendor in North America, as well as academics, end users, consulting
engineers, and government groups participated in its development.
BACnet has been accepted as an open standard by the American National Standards Institute (ANSI)
and the European CEN standards. It is also being adopted as an international ISO standard.
BACnet is designed to include all building systems, lighting, security, fire, heating, ventilation, and air
conditioning. Its purpose is to promote interoperability - sharing data between systems made by different
vendors. It provides the necessary tools to develop a specification for systems that are to be
interoperable. BACnet provides methods and standards for representing information, for requesting and
interpreting information, as well as for transporting information.
SECTION 9 BACNET OVER ARC156
ARCnet is an embedded networking technology well suited for real-time control applications in both the
industrial and commercial marketplaces. Its robust performance and the availability of low-cost silicon
make it the network of choice in BASs.
ARC156 is a unique implementation of ARCnet. ARC156 is similar to master-slave / token passing
(MS/TP). The main difference between the two is speed. ARC156 baud rate is 156K baud whereas
MS/TP tops out at 76.8K baud.
Also, ARC156 uses a separate communications co-processor to handle the network traffic and a
separate processor to handle the program execution. This provides faster processing of applications and
handling of communications on the network. ARC156 is the standard communications method used by
our translators.
9.1 CONFIGURING THE AERCO XPC FOR ARC156
1. Turn off the XPC's power.
2. Using the rotary switches, set the translator's address. Set the Tens (10's) switch to the tens digit of
the address, and set the Ones (1's) switch to the ones digit.
EXAMPLE: If the translator’s address is 01, point the arrow on the Tens (10's) switch to 0 and the arrow
on the Ones (1's) switch to 1. See illustration below.