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3 - FEATURES
3.1 - Management of on and off modes
The unit can be started by the terminal or by the CMS. Parameter P716 is used to authorise or deny CMS control of the unit.
When the unit is operating, an on/off "remote control" input is used to stop the unit.
This may have been previously started up by the HMI in the ON position.
The unit's various operating modes can also be programmed (see time schedule 3.17). The unit has a "frost protection" mode which
is only used when the controlled temperature is the room temperature.
When this is activated the unit is off, but it will automatically restart if the room temperature drops below the P228 set threshold.
To be able to start up the unit, the machine parameters must be locked (P99 = yes)
ATTENTION : if the unit is shut down via the terminal but remote control is authorised (P716=remote), then the air handling
unit may potentially start at any time (if ordered by the CMS, for example).
The unit will only operate if the fresh air temperature is above the minimum threshold (P265). If the unit has been started but the
outdoor temperature is too low, a periodic reminder will be issued every hour, to measure the outdoor temperature and check whether
it is above the threshold.
99
716
228
265
3.2 - Managing setpoints
The PLC manages setpoints 2 setpoint levels (setpoint 1 and setpoint 2) for the temperatures and flow rates/pressures. Setpoints 1 are,
for example used when the building is occupied and setpoints 2 when the building is unoccupied.
Parameter P160 is used to choose between setpoints 1 and 2, either by time schedule or via the J5-U10 on/off input, as well as by
the CMS control or override via the J5-U10 on/off input. In the latter mode, if the On/Off input indicates setpoint 1 mode, it is operating
in setpoint 1; otherwise the operation is as per the last order received from the CMS or time schedule.
Parameter P161 is used to select whether the change in setpoint is based on the temperature setpoints, on the ventilation setpoints
(flow rate or pressure) or on both.
Setting P161
Temperature
Ventilation
Temperature + Ventilation
Note: the setpoint selection input is can be configured NO / NC; this table adopts the input as normally closed. If the actuation takes
place via the CMS, then the input becomes inactive.
160
161
3.3 - Safety and isolation damper
The unit may have up to 4 isolation dampers. They are connected to 2 outlets: outdoor side (fresh air/exit air) and building side (supply
air/return). The presence of the dampers is given by parameter P26.
The insulating damper is activated by an On/Off servomotor with spring-return. The time required for it to open is P108.
When the unit is stopped, this damper is normally closed.
It will open upon the unit start-up request, then after a timeout, the unit will switch to "Run" mode, and the damper kept open, until the
unit is shut down or a "danger" fault appears.
26
108
16
Configuration locked
Control type
Frost protection temperature setpoint
Fresh air temperature limit for unit operation
Setpoint
Temperature
Flow rate or pressure and mixing
Temperature
Flow rate or pressure and mixing
Temperature
Flow rate or pressure and mixing
Setpoint 1 / Setpoint 2 selection
Application of setpoint 1/setpoint 2 selection
Isolation damper
Damper opening time delay
Operation
Selection
Setpoint 1
Setpoint 1
Setpoint 1
Setpoint 1
Setpoint 1
Setpoint 1
Selection
Setpoint 2
Setpoint 2
Setpoint 2
Setpoint 2
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