If a VAM unit is not to be controlled as part of a retail zone (see attached RTD-20 installation instructions for further details on Retail Zone operation modes) then set the DIP switches 1 - 8 to:
* PIR mode: OFF On OFF OFF addr addr addr addr
or
* CO2 mode: OFF On OFF ON addr addr addr addr
addr: DIP switches 5 - 8 are used to set the Modbus network address of this RTD-20 interface.
If no PIR or CO2 sensor is used and the fanspeed is only controlled with Modbus then set the RTD-20 to VAM CO2 mode.
Close the contacts between S2 and '0V' (on the same terminal block). This will enable the VAM unit.
Note that a wired remote controller has to be set as SUB P1P2 device. This is changed in the wired remote controller's settings.
The Modbus control registers are listed on page 20 of the RTD-20 installation instructions.
Monitoring (Readback registers): Note that when using Modbus the readback registers (Modbus 'input registers') are all listed in the attached RTD-NET installation instructions.