VRF Protocol Gateway
14
7.2.3 Setting of communication connection
RS
485
-1
R+
R-
(A
1) (
B1
)
RS
485
-1
R+
R-
(A
1) (
B1
)
①
②
③
Gateway
Gateway
Fig. 7.5 Connection between gateway and BMS via Modbus
Step 1: Ensure the first gateway that should connect to BMS terminal, connect
the RS485-1 communication interfaces R+ and R- of the gateway to the BMS
terminal with communication cable; as shown in Step
①
in the figure.
Step 2: Connect the RS485-1 communication interfaces R+ and R- of the
gateway to the RS485-1 communication interfaces R+ and R- of the second
gateway with communication cable; as shown in Step
②
in the figure.
Step 3: Connect other gateways in turn; as shown in Step
③
in the figure.
7.3 Gateway and BMS adopt Modbus RTU Protocol
Communication Connecting Method
7.3.1 Material Selection for Communication Iine
(1) Model selection of Gateway and BMS communication line shall use
standard Ethernet communication line, the length of network cable between
gateway and router (computer, switchboard, etc.) shall not exceed 80m
