Order No. 2104 ..
The following two images show 2-point feedback control for the mixed operating mode "Heating
and cooling", distinguishing between heating mode (Figure 20) and cooling mode (Figure 20).
The images take two temperature setpoints, a non-inverted command value output and an
automatic operating mode change-over. When the operating mode is switched over via the
object, an upper hysteresis for heating and a lower hysteresis for cooling can be configured.
Figure 22: 2-point feedback control for mixed "Heating and cooling" mode with active heating
mode.
Figure 23: 2-point feedback control for mixed "Heating and cooling" mode with active cooling
operation.
Depending on the switching state, the command value "1" or "0" will be output if the values
exceed or remain under the hysteresis limits or the setpoints.
i
It has to be pointed out that the message objects for heating and cooling will already
become active as soon as the temperature falls short of the temperature setpoint of the
active operating mode in case of heating or exceeds the temperature setpoint in case of
cooling. In this case the hysteresis is not being considered.
An additional 2-point feedback control heating or cooling level works exactly the same as the
2-point feedback control of the basic level. The difference is that the setpoint and the hysteresis
values will shift by taking into account the configured level offset.
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Software "KNX CO2 sensor"
Functional description
