http://www.loxone.com/enuk/service/documentation/extensions/rs485.html
... On the configuration program just go to Periphery - Devices - RS485 Extension and
just use the following communication parameters: 8 Data, 1 Stop, No Parity, Baud rate : 9600.
Now add a RS485 actuator. Click use as digital output,
write \xFF\x01\x01 on "Command for on" and \xFF\x01\x00 on "Command for off"
and you can control the first relay channel.
Repeat the above for the other relays (\xFF\x02\x01 and \xFF\x02\x00 for the second, so on)....
Thank you Vampiris!
http://www.info.kmtronic.com/Loxone_and_KMTronic_RS485_Relay_Board.pdf