sauter NRT407, Руководство пользователя

Страница: 28 / 76

28 Part III Configuration NRT407 manual
Reversed sequence In some applications, e.g. free cooling, it may be desirable to reverse the sequence of Y2 and
Y3 (i.e., to open Y3 before Y2). This function is a configuration of the control mode
Heating/Cooling/VAV. When the function is active, the sequence of Y2 and Y3 will be
reversed, i.e. Y3 will open 0…100 % when controller output is in the range of 0…48 %
and Y2 will open 0…100 % when the controller output is 52…100 %. See the figure below:
At forced ventilation, Y3 will open fully as before, and Y2 will control depending on
temperature. However, Y2 will not give any output unless the controller output is above
52 %.
This function is only valid for models with Y3 output.
Heating/heating or cooling via change-over
For models offering fan functionality, a function for control of a heating battery on UO1 in
sequence with change-over on UO2 is available. When this has been performed, the start
sequence of UO1/UO2 is changed along with the limits for fan start.
The change-over function will be used to switch between summer and winter mode. UO2
will be used as a cooling actuator in summer mode and as a heating actuator in winter mode.
In summer mode, NRT will function as a regular heating/cooling controller.
In winter mode, NRT will function as a heating/heating controller. UO2 will initiate first and
UO1 second. The electrical heating battery connected to UO1 will start only if the ordinary
heat battery on UO2 cannot meet the heating demand. When a heating demand exists, the
output of UO2 is 0…100 % linear to the heating demand 0…48 % and UO1 0…100 % to the
heating demand 52…100 %. When the heating demand is 48…52 % UO2 will always output
100 % and UO1 0 %.