Specifications

Field Controller Main Code Release
For Remote Field Bus compatibility, the Main Code for the field controllers you connect to remotely must be at
Metasys system Release 5.3 or later. Remote field bus communication is not as robust with controllers that are
running older releases of the Metasys system.
CCT Pass Through Loading
Generally, you can upload and download code and applications with CCT Pass Through for devices directly connected
to a Remote Field Bus (subject to router message load levels). However, you cannot use CCT Pass Through to
download code to an IOM connected to the SA bus of a field controller. In these situations, use a Wireless
Commissioning Controller at the remote location.
Device and Point Mapping
When you define a Remote Field Bus, be sure to map all devices and points at the remote controllers through the
same Remote Field Bus. For most networks, a detrimental increase in router traffic occurs if multiple integrations
use the same router and network number. This is true regardless of where the multiple integrations are defined or
if a BACnet Integration is used.
Remote Field Bus Status and Statistics Attributes
With the local field bus, the status and statistics values are obtained directly from the MS/TP communication software,
which has direct access to the MS/TP communication frames. However, with the Remote Field Bus, the status and
statistics values must be obtained from one of the remote FEC Family BACnet controllers communicating through
the BACnet Router. When at least one Metasys MS/TP field controller is mapped to the Remote Field Bus as an
FEC Family BACnet device, the system can retrieve and display the status and statistics values from the Remote
Field Bus. Be aware that if this field controller goes offline and a different FEC Family field controller is selected to
provide remote bus statistics, the values obtained may abruptly change because the values are from a different
controller. This is normal operation.
The following Metasys attributes are located under the Diagnostics tab of a Remote Field Bus.
Logging Object Reference
This attribute indicates the remote Metasys MS/TP field controller configured for obtaining MS/TP trunk status and
statistics values. The device name appears if available; otherwise, the MAC address on the MS/TP trunk appears.
The value is empty for a local field bus, or if no Metasys field controller is available or known. The remote Metasys
device is chosen by first looking for an online, mapped FEC Family BACnet device. If none is found, then the Analyze
Field Bus command results (if any) are scanned for a possible FEC family device.
Bus Health Index and Bus Performance Index
Trunk health and performance moving average calculations are generally delayed one update time (usually one
minute) on a Remote Field Bus due to the delays in reading raw statistics values remotely. As mentioned previously,
the numbers reported experience a transient glitch if you change the Metasys BACnet device used to gather statistics.
Port Status
The value of this attribute is Remote Trunk for a Remote Field Bus. For an online local field bus, the value of this
attribute is Active.
Remote Field Bus Status Commands
The Site Management Portal UI offers a few commands that relate to Remote Field Bus operation.
Latch Statistics
The Latch Statistics command is redirected to the FEC Family BACnet Device used for collecting MS/TP trunk
statistics.
Clear Statistics
15MS/TP Communications Bus Technical Bulletin