System Control; System States - Salda MCB Technical Manual

In Stand-by mode the system is shut down for a permissible period (based on the Stand-by mode blocking function settings).
The Building protection mode is designed to protect premises against moisture accumulation. The system operates at speed 1. Based
on manufacturer's parameters (by default) this mode controls the temperature (the desirable one is indicated), but, if necessary, it can be
switched off, i.e. to activate the energy saving mode. Also, if necessary, full recirculation function is activated. (ADJUSTER › USER SETTINGS ›
BUILDING PROTECTION MODE TEMPERATURE or USER › MENU › SETTINGS › BUILDING PROTECTION).
After activating the energy saving mode, temperature is maintained only by the heat exchanger. It will seek to maintain the current temper-
ature in the room; however, if the supply air temperature falls below the minimal supply air temperature level, heaters will be activated and
they will maintain a temperature one degree above the minimum. Also, if the supply air temperature rises above the maximal supply air
temperature level, coolers will be activated and they will maintain a temperature one degree below the maximum.
Economy mode is designed to save energy when people are absent from the premises. The system operates at speed 2. Based on manu-
facturer's parameters this mode controls the temperature maintaining (the desirable one is indicated), but, if necessary, it can be switched
off, i.e. to activate the energy saving mode. Also full recirculation function is activated. (ADJUSTER › USER SETTINGS › ECONOMY MODE TEMPER-
ATURE or USER › MENU › SETTINGS › ECONOMY MODE).
Comfort mode is running when people are present in the premises. The system operates at speed 3. In this mode the temperature is always
maintained – it is set in the main window (ADJUSTER › VENTILATION CONTROL or USER › SET POINT).
In each of these modes, a fixed position for the recirculation dampers can be set (ADJUSTER › USER SETTINGS › FIXED RECIRCULATION POSITION)

5.2. SYSTEM CONTROL

System modes are changed by the following functions (indicated in a sequential order):
› Weekly Schedule;
› Switching on is activated from an external contactor;
› Manual mode selection;
› Holiday Schedule;
› Stand-by mode blocking.
Based on the Weekly Schedule the system decides in what mode it will be operating; however, the user may change it manually. The system
informs when the next mode change is scheduled. After power loss the mode is selected based on the Weekly Schedule; however, if it is not set,
the mode that was set before the power loss will be activated.
The user may change modes even when the switching on is activated from an external contactor. The only case when it is not possible – active
period of Holiday Schedule of which the system informs and which must be changed to avoid blocking.
Stand-by mode can be blocked by selected parameters. If at least one of the above functions changes its mode into Stand-by mode, it must be
checked whether this mode is not currently blocked. If it is blocked, the previous mode shall be activated.
The function order is provided below.
START >
› READING OF INPUT DATA;
› WEEKLY SCHEDULE;
› MODE EXTERNAL SWITCH;
› USER ENTERED DATA;
› HOLIDAY SCHEDULE;
› STAND-BY MODE SCHEDULE;
› STAND-BY MODE BLOCKING;
› PROTECTION AGAINST DRYNESS;
› BOOST VENTILATION;
› AIR HANDLING UNIT OPERATING ALGORITHM;
› PROTECTION;
› BLOCKING OF AIR HANDLING UNIT OPERATING ALGORITHM;
› MANUAL CONTROL OF COMPONENTS;
› DATA ENTERING INTO OUTPUTS AND USER ENVIRONMENT.
END <

5.3. SYSTEM STATES

This field informs a user about the existing system state. It is displayed in the main window ADJUSTER › VENTILATION CONTROL or the main window
of the user environment. The table below shows possible system states.
SYSTEM STATE
Stand-by mode
Building protection mode
Economy mode
Comfort mode
Emergency run
Preparing
Opening dampers
BOOST function activated
Cooling heaters
MCB_miniMCB v2019.1
DESCRIPTION
System operates in Stand-by mode.
System operates in Building protection mode
System operates in Economy mode
System operates in comfort mode
System operates in emergency mode (for details refer to alarms section)
System is preparing for operation (pre-heating of water heaters, etc.)
Dampers are opened
BOOST function is active
Electric heaters are cooled down prior to shutdown of fans
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