C0240111-04-05-GB
Fase di avviamento controllato
= Controlled starting phase
Adattamento zona neutra
= Adaptation to dead area
Temperatura uscita evaporatore
= Outlet temperature of evaporator
Temperatura ingresso evaporatore = Inlet temperature of evaporator
1 compressore attivo
= 1 compressor active
2 compressori attivi
= 2 compressors active
Figure 5.4
:
example of real data with quick-mind outlet adjustment (x-axis: time in [s]; y-axis: Tout in [
°C
] )
.
This is an example of start-up with a very high initial temperature compared with the setpoint (7°C).
About 10 seconds after data acquisition began, one compressor switches on. The second compressor
does not switch on immediately as the algorithm which handles start-up checks if one compressor is
enough to return delivery temperature to the setpoint and avoid unnecessary start-ups. As the delivery
temperature is still at 12 °C after about 200 seconds, the second compressor is also switched on,
otherwise it would take too long to reach setpoint.
Following the controlled starting phase, the delivery temperature falls until it “enters” the dead area. The
algorithm (at t= 350 s) begins to adapt the amplitude of the dead area in order to respect compressor
safety times. As can be seen, the dead area is later reduced (t= 780 s, 950 s) to the absolute minimum
amplitude which allows safety times to be respected. It can also be seen that the compressors are
activated and deactivated when the outlet temperature reaches the upper or lower limits of the dead
area. The example shows that outlet temperature varies by about 3.5 °C during regular operation.
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