Vents VUT 300 WH EC, Руководство пользователя

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Structure and operating logic of automatic control system:
Automatic control system has winter and summer operation modes. The mode is selected
automatically depending on the outside temperature: if the outside temperature is above the set
point (0°C by default) the system operates in summer mode. If the temperature drops below this set
point the system automatically switches to winter mode.
Basic system functions in summer mode:
- maintaining set supply air temperature level by means of controlling the heater regulation
valve;
- closing of the heater regulation valve and external air dampers during the fan shutdown.
Extra system functions in winter mode:
- maintaining the set supply air temperature level by means of controlling the heat medium
regulation valve;
- preheating of the water coils before the fan start-up within the time period set by PLC
( parameter Q-02, factory setting 180 seconds, see table 3 by means of 100% opening the heater
regulation valve to provide full air stream through the heating coils. This function is disabled by
default, the factory setting is OFF. It is activated from the PLC, parameter Q-14, see table 2.
- maintaining set minimum return water temperature level when the fans are turned on.
This level is set from the PLC menu, parameter Q-01 (refer the table 2), the default setting is +20°C.
Both in winter and summer modes, the control system enables freezing protection of the water
coils by the thermostat TS1 installed downstream from the heating coils.
In case of freezing danger the fans are turned off, the external air dampers are closed and the
heat medium regulating is 100% opened to enable full stream of heat medium through the coils. The
circulation pump is started.
The control system has extra option to restart the fans after power failure. This option is activated
and adjusted from the controller menu.