Individual Control
To control an indoor unit individually one RTD-10 interface is needed for each indoor unit.
Group Control
Up to 16 indoor units (or VAMs) can be wired to the same RTD-10 (via the P1P2 network) - see page 7 of the attached RTD-10 installation instructions. In this case - 'Group Control' - any command from (the BMS to) the RTD-10 is broadcast to all units within the same group.
Note that in this case the relays signal FAULT or RUN for any of the connected indoor units.
If Modbus is used then group data can be read from Holding and Input registers, and individual unit data can be read from Input registers (see the attached RTD-NET installation instructions for a list of available Modbus registers). For further details please read the article 'How to read data of a unit which is in a group'.
*Note that in Duty/Standby mode to access the Modbus registers an additional Modbus gateway is required (we recommend our interface RTD-DSX - see attached RTD-DSX installation instructions), because the Duty/Standby Master RTD-10 acts as a Modbus master.
P1P2 (Wired Remote Controller) Network
Up to two remote controllers are allowed on the P1P2 wired remote controller network. The RTD-10 acts as a wired rmote controller. Therefore, only one additional wired remote controller is allowed in combination with the RTD-10 on the P1P2 network.