26
6
.2.3 MODBUS interface
The indoor unit of this series has MODBUS interface. If the user needs to connect the unit to the
management system of the building, please enquire Gree for the MODBUS protocol.
Figure 2-7-9
(1) 1. Interface instruction:
1) The printing is COM-BMS1 and the interface type is B4B-XH-K3;
2) Electrical characteristic: baud rate: 9600bps; standard: RS485;
3) Working principle:
The indoor mainboard can send out the unit operation state through this interface and receive
logical control information to realize control and monitor of the unit.
(2) Function instructions:
In order to achieve this function, set the address mode and address through wired controller. Please
refer to Point 3 for the setting method. You must set the address mode into long-distance control address
mode.
The address mode is defaulted to be connecting to centralized controller mode and the defaulted
address is 1.
(3) Setting method:
1) Firstly, set the address mode of wired controller into centralized controller address mode. The
setting method is:
Under off state of the unit, press Function and Timer buttons at the same time for 5s to go to the
debugging menu. Press Mode button to adjust to
―10‖ in temperature displaying zone. Timer zone
displays setting state and press ▲ or ▼ button to adjust. There are 2 selections:
2) Centralized controller address mode (LCD displays 00)
3) Long-distance control address mode (LCD displays 01)
Choose the second selection and then press Enter/Cancel button to save and exit setting. Now, the
address of wired controller is set to match the address of long-distance control. The unit will memorize
this setting status. The setting value will be memorized after power failure. The detailed setting is as
