Contemporary Control Systems BASremote Application Guide - Manual (Page 5)

AG-BASR0000-BC0 Page 5
Application Guide — BASremote
C
ONTR LS O
®
CONTEMPORARY
Application #2 — Modbus Serial to BACnet Gateway for Unifying Data
Although BACnet is quite popular, there is an
abundance of Modbus Serial equipment that needs to
attach to the building automation system. There are
two approaches to the problem. The first is to route
Modbus Serial messages from the BASremote Master
MB port to Modbus TCP clients residing on Ethernet.
This is the simplest approach requiring minimal
configuration. The BASremote Master would act as a
proxy for a Modbus TCP client, initiating a command to
a connected Modbus Serial slave. When the slave
responds, the message is forwarded to the Modbus
TCP client. The resident BASremote Master I/O can
be queried in a similar fashion.
The second approach is to utilize the gateway
capability within the BASremote Master. Using an
off-line spreadsheet, Modbus registers and slave
addresses are mapped along side BACnet object
instances. The spreadsheet creates a CSV file which
is downloaded into the BASremote Master for periodic
scanning. The result is that attached Modbus Serial
devices can be viewed as BACnet objects.
BASremote Master
Modbus 2 BACnet Device Profiling
Power
Meter
Drive
Modbus