When several indoor units are wired to the same FDP3 interface on the wired remote controller TCC-NET network they are treated as a group. This means any command sent to the FDP3 interface applies to all these units. However, data (like Fault code, RA temperature, Thermo On etc) can be read individually from each indoor unit via Modbus. For lists of available readback data please refer to the installation instructions of the FDP3 interface in use.
- Please note that In Group control the device controlling the louver function may have to be the master TCC-net device (please refer to the indoor unit's service manual on group control).
General (Group) vs Individual (Unit) Readback data
The FDP3 interface to which a group of indoor units is wired allows reading group and (individual) unit data. General data can be any value in any (Modbus) Holding register, or in specific Input Registers.
If for example a Holding register's value is changed through a hardwired input (S1 - S6..note that not all FDP3 interfaces have hardwired inputs) then this value is applicable for all units and can be read using the Modbus command for reading Holding Registers.
The difference between (Modbus) group Input Registers and (individual) unit Input Registers is:
The group registers hold information which may be the average value of the units, data, or status of at least one of the units while the unit registers hold information of a specific unit within the group.
*Note: Input Registers do not affect operation of the indoor units.
Example:
FDP3-Modbus: Read the Return Air temperature of a group of 8 units (the 'I' before the register address inidicates that this is an Input Register):
* I0023 gives average of all units' return air temperatures
* I0123 gives return air temperature of unit 1
* I0223 gives return air temperature of unit 2
...
* I0823 gives return air temperature of unit 08
The value of a Readback Input Registers for which no indoor unit exists is '0'.
As shown above the Input Register address of unit readback registers is 'xx23' ('xx' > 0). The 'xx' is the remote controller TCC-NET network address of this specifc indoor unit. This remote controller TCC-NET address cannot be set with the FDP3 interface. For further information on setting this address please refer to the indoor unit's installation instructions, the remote controller's manuals, or contact Toshiba Technical Support.