VRV system control from KNX bus with CoolMaster

Example: VRV system control from KNX bus with CoolMaster

Task

If there is a necessity to control VRV systems from your fieldbus system you can use/integrate one of the following control methods:

• InfraRed
• ModBus over RS-485 or LAN
• RS-232

Using the above methods you can do quite cost-effective integration of VRV systems in your KNX, BACnet, EnOcean etc. field-buses and common visualization.

The following script will show how to interconnect CoolMaster VRV controller to LogicMachine3 over RS-232 serial port. The following VRV systems can be integrated: Daikin, Fujitsu, Gree, Hitachi, LG, Mitsubishi, Mitsubishi Heavy, Panasonic, Samsung, Sanyo, Toshiba.

RS-232 integration

If your LogicMachine does not have RS-232, you can integrate it through USB to RS232 converter based on CP210x, FT232, PL2303, MCT U232 chips. 

Objects

For correct work objects should be named correctly:

• 101 on/off – binary
• 101 temp – 2 byte floating point
• 101 mode – 1 byte (0 = cool, 1 = dry, 2 = heat)
• 101 fspeed – 1 byte (0 = low, 1 = medium, 2 = high, 3 = auto)

all on/off – binary object to turn all blocks on and off at once

For status objects we add ‘status’ after the name, example:

• 101 on/off status
• 101 temp status

For all objects you should set tag = VRV

Resident script

Add the following resident script with 0 interval. Replace ‘/dev/RS232’ with the respective name of the port of your LogicMachine.