Controls
28 Chiller Air-cooled Screw
Connector
MODBUS
Pin
Description
RX2/D2+
TX2/D2 -
Wire No.
MODBUS on RS-485: D+
MODBUS on RS- 485: D -
CN6
(RTDI)
RTD1+
RTD1-
RTD1-
RTD2+
RTD2-
RTD2-
RTD3+
RTD3-
RTD3-
RTD4+
RTD4-
RTD4-
RTD5+
RTD5-
RTD5-
11
10
13
12
15
14
17
16
19
18
Chilled Water In Temperature
Chilled Water Out Temperature
Compressor Exhaust Temperature
Ambient Temperature
Refrigerant Cond Out Temperature
-
-
-
-
-
-
-
-
-
-
-
-
Table 7
The MODBUS communication capability is provided by standard. Using the MODBUS communication, the chiller can be
integrated in conventional BMS network. The MODBUS also can be translated to LonWorks or BACnet using 3rd party
translator for flexible connectivity to BMS network. The communication configuration of the MODBUS communication is
as following:
1) Signal: RS-485
2) Mode: RTU
3) Baud rate: 19,200BPS
4) Parity: even
5) Character: 8 Bit
6) Stop Bit: 2 Bit