GMV DC Inverter VRF 
45 
When two wired controllers control multiple IDUs, the wired controller can be connected to 
any one IDU, provided that the connected IDU is of the same series. Meanwhile, one and only 
one  of  the  wired  controllers  must  be  set  as  a  slave  controller.  At  most  16  IDUs  can  be 
controlled by wired controllers and the connected IDUs shall be within a same IDU network. 
No matter when unit is turned on or off, slave controller can be set. 
How to set a slave controller: hold “function” button on the designated controller for 5s, and 
temperature zone displays C00. Continue holding “function” button for 5s and setting screen of 
controller parameter will come out. Default temperature zone displays P00. 
Press button o button to select parameter code P13. Press “mode” button to switch to 
setup of parameter values. Then the parameter value will blink. Press button or button to 
select code 02. And then press “confirm/cancel” to finish setting. 
Press  “confirm/cancel”  to  return  to  the  previous  display  until  you  exit  from  the  setup  of 
parameter values. 
Below are user’s parameter settings: 
Set up 
address for 
wired 
controller 
01: master wired 
controller 
02: slave wired 
controller 
When 2 wired controllers control one or more 
IDUs, they shall have different addresses. 
Slave wired controller (02) can’t set up units’ 
parameters except its own address. 
4.7.3 Communication connection between duct type IDU and light board receiver 
When the duct type IDU needs to be connected to light board remote receiver, it can be 
connected via Dsp1 and Dsp2 on the IDU main board. 
Main board interface of corresponding IDU   
Dsp1 (direct to 8-core interface) 
Dsp2 (direct to 9-core interface) 
 
Fig. 4.7.7