Restoring Factory Defaults; Fan Control; Fan Protection By Rotating Speed; Air Flow Protection Based On Pressure - Salda MCB Technical Manual

5.32. RESTORING FACTORY DEFAULTS

If set parameters result in incorrect operation of the system, you can always restore the factory defaults in the service environment window SER-
VICE › MAIN › FACTORY SETTINGS.

5.33. FAN CONTROL

The preferred air-flow can be indicated in percentage or in 4 fixed speeds where each of them is dedicated to a relevant system mode:
› Building protection;
› Economy;
› Comfort;
› Maximum power.
Fan speed can be controlled by:
› Percentage - speed in percentage is indicated in the adjuster environment window ADJUSTER › AIR FLOWS ADJUSTING: 0 % corresponds to 0,
and 100 % – 10 V control signal voltage;
› Pressure - the maximum system pressure is indicated, which based on speed settings in the adjuster environment ADJUSTER › AIR FLOWS
ADJUSTING means 100 % air-flow;
› Air-flow (m /h) - K factors of supply and exhaust air and the maximum system air-flow (m
3
in the adjuster environment ADJUSTER › AIR FLOWS ADJUSTING means 100 %.
Fans based on air-flow and pressure are controlled by PID controller and its coefficients are indicated in the adjuster environment section ADJUST-
ER › PID CONTROLLERS ADJUSTING › FANS SPEED CONTROL BY AIR FLOW OR PRESSURE. Every fan is controlled individually.
In the service environment window SERVICE › FANS › FANS SPEED CONTROL you can limit the minimum and maximum fan control signal voltage.
Based on manufacturer set parameters, the minimum 2V voltage is indicated, which means that 0V voltage signal is sent when fans are off, and
2V voltage signal is immediately switched on when rotation is required.
It is possible to specify the nominal flows of supply and exhaust air. Then, the maximal air flow is calculated automatically.

5.33.1. FAN PROTECTION BY ROTATING SPEED

If fans have TACHO outputs, the fan failure can be identified by their rotating speed. If the system sends the signal to fans to rotate and they fail
to rotate, then the protection is activated, the system is shut down and alarm is displayed.
Function is switched on/off in the service environment section SERVICE › FANS › FANS PROTECTION BY RPM.
If this protection is disabled, the same inputs are used for the warning signal, i.e. if the main fan failed and reserve fan is still working, then the
signal is transmitted to this input and warning is displayed about fan fault (system is not stopped).

5.33.2. AIR FLOW PROTECTION BASED ON PRESSURE

When this protection is activated the system must reach the required pressure or air-flow. If it does not happen within the indicated period of time,
the protection is activated, the unit is shut down and alarm is displayed. This may happen due to air flow/pressure gauge failures, pressure hose
defect, clogged flow, impeller defect, incorrect factor K, etc.
Function is switched on/off and time is set in the service environment section SERVICE › FANS › AIR FLOW PROTECTIONS.

5.33.3. PROTECTION OF PREMISES WITH FIREPLACES

This protection is used for buildings with fireplaces. It protects against improper differential air pressure, which can result in appearance of flue gas
(carbon black). A pressure switch must be connected to a dedicated digital input, which measures differential pressure in premises and inside a
chimney. Upon activation of this protection, the unit is shut down by the activated pressure switch and warning is displayed.
Function is switched on/off in the service environment section SERVICE › FANS › AIR FLOW PROTECTIONS.

5.33.4. SLOWING DOWN AIR-FLOWS BASED ON TEMPERATURE

If supply air temperature is more important than the air-flow, the slowing down function may be switched on. If full heating/cooling capacity is used,
but the preferred temperature is not reached, air-flow starts slowing down to reach the goal.
Function is switched on/off in the service environment section SERVICE › FANS › AIR FLOW PROTECTIONS.

5.33.5. CONTINUOUS TEMPERATURE MAINTAINING BY SLOWING DOWN THE FANS

This function helps to save energy, when air-flow is changed. It is active, when the fans are controlled by percentage, since PID controllers do it
automatically when it is controlled based on air-flow or pressure. Fast change of air-flow imbalances the temperature maintaining function, thus
energy is wasted. If a user sets a higher air-flow, this function starts gradually increasing the air-flow and gradually slows down the speed of
change when it approaches the set value. This way the temperature maintaining function suffers less stress and consumes less energy. If the user
reduces the air-flow, the system switches off the coolers and heaters to prevent from building up of heat/cold wave and gradually changes the
air-flow. Afterwards the heaters and coolers continue operating as required.
5.33.6. THE MINIMAL OUTDOOR AIR TEMPERATURE OF THE FREON COOLER/HEATER
The minimal fresh air temperature, at which the DX cooler/heater can operate, is indicated. If the fresh air temperature drops below the specified
limit, then the DX cooler/heater is shut down.
12 | EN
/h) are displayed, which based on speed settings
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MCB_miniMCB v2019.1