Robur Direct Digital Controller, Installation, Use And Programming Manual

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Direct Digital Controller
Direct Digital Controller fw 4.013 – Ed. 01/2013
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1 - Select the icon from the initial screen and press the knob to gain access to the screen displaying the
operating parameters of base and separable DHW plant.
2 - Select the symbol positioned above to gain access to the “ Base DHW plant control” menu ”.
3 - Select the symbol positioned below to gain access to the “ Separable DHW plant control” menu ”.
4 - In both cases (“Base DHW plant control” and “Separable DHW plant control”) the screen shown in the
figure below will be displayed on the screen.
The figure shows the screen of the “DHW plant control” menu and the
relevant button described below.
Main ON/OFF switch.
Turn the knob to position the cursor on the button and press the same to
activate it (symbol of the ON/OFF button in the ON position ).
In case of Multi-DDC plant, it
is ON only on the Master DDC; on the Slave DDC(s) it reflects the ON/OFF status set on the Master.
The plant may be activated only if either of the following conditions applies:
ƒ
The water T timer cycles are disabled and the RY contact (cooling plant) or RW contact (heating plant) is
closed;
ƒ
If water T timer cycles are enabled, the plant may only be switched on if the corresponding external contact
is closed and if the water T timer is programmed to be on at the time.
Figure 26 shows the DDC connection diagram for the RYWm operating mode. EXTERNAL ON/OFF
COMMAND.