99
Pre-Commissioning
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If the chiller enters the Modbus remote mode, all the information can only be monitored through the HMI. Actual operation control (start / stop or
changing the set temperature) can only be performed through the external controller. To control from the HMI, change the control mode to “Local”.
Remote communication error CH10009 will occur when the communication is disconnected between the HMI and external controllers. When com-
munication is recovered, it will automatically resume. If the remote Modbus connection is not used, reset the power of the main PCB of the chiller to
cancel the alarm.
Modbus Interlock Protocol Details
The protocol details for Modbus interlock of external devices are:
• Physical layer: RS-485 serial line
• Mode: Modbus RTU mode
• Baud rate: 9,600
• Parity: None parity
• One (1) stop bit
• Applied function codes
Function Code
Sub-function
Function Name
Start Address From Main Device
0x01
None
Read Coil Register
Address-1
0x02
None
Read Discrete Input
Register Address-10001
0x03
None
Read Holding
Register Address-40001
0x04
None
Read Input
Register Address-30001
0x05
None
Write Single Coil
Register Address-1
0x06
None
Write Single Holding
Register Address-40001
0xF1~FF
Reserved for Exception Code
-
-
Figure 45: Applied Function Codes.
See the Modbus protocols in the following pages.
MODBUS PROTOCOL