Gree GMV5 Series Service Manual page 285

The RS485 bus should be terminated with a matched resistance to avoid signal reflex along the
transmission line.
In application of the Modbus gateway, an upper unit as the terminal unit is usually coupled with a RS485
matched resistance, so this gateway is factory defaulted to be without a matched resistance.
When the Modbus gateway is required to be set with a matched resistance, the seventh position of this
DIP switch should be set as shown in the figure above to ―0‖ and the gateway should be located at the
end of the RS485 bus.
Function
(5) Function DIP Switch-First IDU No. Setting
As shown in the topological air conditioning network, each IDU has an identification number.
The sixth position of the function DIP switch is intended to set the first IDU number which is used to
define the range of the IDUs under the control of the gateway.
The number of IDUs ranges from 1 to 255.
When the first IDU number is set to ―1‖, it indicates the range of the IDUs under the control of the
gateway is 1 through 128.
When the first IDU number is set to ―129‖, it indicates the range of the IDUs under the control of the
gateway is 129 through 255.
When the IDU number is beyond the range defined by the gateway, it should be modified.
The following figure shows how to set the No. of the first IDU underthe control of the gateway:
0
1
1 2 3 4
Function DIP
2. Indicating LED
Running
RX
CAN
TX
RX
RS485-1
TX
RX
RS232
TX
RX
RS485-2
TX
GMV5 DC INVERTER VRF UNITS SERVICE MANUAL
5 6 7 8
Alarm Power
It flashes when the gateway receives data from the target equipment
(like, the air conditioning system).
It flashes when data is communicated to the target equipment (like, the
air conditioning system).
It flashes when the gateway receives data from the monitoring PC or
BMS.
It flashes when data is communicated to the monitoring PC or BMS.
It is reserved.
It is reserved.
It is reserved.
It is reserved.
With
matched
Without
resistance
matched
configured
resistance
configured
indicates the position of toggle switch
First indoor unit
number: 129
First indoor
unit number :1
6 6
Projecting lever
282
0
1