We reserve the right to make changes without prior notice
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The differential pressure value at the fan nozzle is measured by air pressure differential probes.
The 0/10V control signal is sent to the fans only after closing of the digital output that controls the main
ventilation system.
When the unit off command is given, the digital output of the main ventilation system is opened on condition
that the fan analogue signal is set to zero.
6.3.2 Control logic of supply and return plug-fans on temperature setpoint
For units equipped with plug-fans on supply airflow and, if requested by the configuration, also on return airflow,
the control allows to set different logics when the air temperature has reached the setpoint (Tset_s in summer
e Tset_w in winter):
1. No changes on supply (return) airflow. This function keeps the same airflow to the value Aset_1 also
when the unit has reached the setpoint ;
2. Decrease supply (return) airflow. This function adjusts and keeps the airflow to the new set Aset_2 until
a different request by temperature regulation (see chapter 6.4);
3. logic must be activated only for full recirculation unit.
3. Supply plug-fan switch-off. This function switches plug-fans off and keeps them off until a different
request by temperature regulation (see chapter 6.4).
The main purpose of logics 2 and 3 is to reduce the electric consumption for the plug-fans when there is no
need of temperature regulation.
The logic 3. can be activated only for full recirculation unit and AND IF the return probe is installed directly in
the conditioned room. Indeed, for units with dampers, the fans switching-off doesn’t allow the immission of
external air in the conditioned ambient.
The new airflow set for logic 2 is settable only within a factory set range.