CIAT AirCompact Control, Control Manual

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1.6
Functional analysis of the control
1.6.1
Management of on and off modes
Starting up and switching off will take place locally by pressing on the

and

keys on the display.
Remote control is available and carried out by a potential-free contact between terminals 1 and 2 in place of the factory-installed
shunt.
The unit is to be switched on/off by the CMS.
The unit will start up if the 3 running orders are actuated (on the display, on the remote control and via the CMS, depending on the
configuration).
If one of the 3 orders is in "Off" mode, the unit will be stopped.
1.6.2
Safety and insulating damper
The insulating damper is activated by an On/Off servomotor with spring-return.
When the unit is stopped, this damper is normally closed.
When unit start-up is requested, it will open and the controller will wait whilst the servomotor opens, then the unit will be switched
to "On" and the damper held open unit the next request to stop the unit or, if a safety damper is being used, for the appearance of
the antifreeze protection alarm.
1.6.3
Antifreeze thermostat
The antifreeze thermostat has a manual reset and it is constantly monitored once the controller is switched on.
If an antifreeze alarm is activated, the fresh air damper is closed, the valves on the hot water coil installed in the air handling unit
are opened fully and the fault is signalled.
A frost prevention function is available once the unit is switched off. This consists of leaving the hot water coil valves slightly open
(adjustable value) to maintain pre-heating.
1.6.4
Fire fault
The fire fault contact (option) connected to a PLC input is used to signal the appearance of the fire fault and disables the fans.
Air flow rate OK
Unit off
Unit powered up
Unit on Manual mode
Switching on
OR critical fault
On request
AND on authorisation
AND NO critical fault
At least 1 override requested
No override requested
Off request
Off request
SMR