GMV DC Inverter VRF 
38 
Power cord and communication wire should be separated, with a distance of more than 
20cm. Otherwise, system’s communication may not work well. 
(5) Steps of power cord connection: 
1) Knock off the cross-through opening that’s used for leading the external power cord, 
with the cross-through rubber ring on the opening. Then lead the cable through the 
opening. Connect L1, L2, L3, N of power cord and ground wire separately to the 
positions on wiring board (for power supply) that are marked with L1, L2, L3, N and the 
ground screw nearby. 
2) Fasten the power cord with cable tie. 
3) Lay the power cable and communication cable for the ODU according to the marker of 
external connection circuit diagram. 
4.6 System Communication 
4.6.1 Communication system include: 
(1) Communication among outdoor basic modules; 
(2) Communication between ODU and IDU; 
(3) Communication among IDUs; 
(4) Communication between IDU and wired controller; 
(5) Connection between IDU and light board receiver; 
(6) Communication between different refrigeration systems; 
(7) Graphics of general communication connection