GREE                                                          DC Inverter Multi VRF System II Service Manual 
18 
 
3.3.2.3 Operation instruction 
z  Power LED: a red light. If the red light is on, it indicates normal power supply. If the red light is off, 
it indicates the power supply of converter is not normal. 
z  Communication LEDs: yellow lights. When converter is working and the computer is transmitting 
data, the TX data transmitting light will be flickering. When units are uploading data to the 
computer, the RX data receiving light will be flickering. 
z  When converter is under RS485 data transferring mode, the function LED of RS485 to USB will 
be on. 
z  When converter is under CAN data transferring mode, the function LED of CAN to USB will be 
on. 
z When converter is under HBS data transferring mode, the function LED of HBS to USB will be 
on. 
z  USB interface: connect USB data wire. 
z CAN interface: When converter is under CAN communication mode, connect air conditioner’s 
CAN data interface. CAN interface exhibits no polarity (A and B are equal).