Aircel AES Series, Руководство пользователя

Страница: 10 / 84

| VF, DHT, AES Series Manual
Refrigerated Air Dryer User Manual
6
2.5 Digital Scroll Compressor
Aircel AES Series dryers employ the Copeland Scroll Digital™
compressor to allow consistent dew point performance
while matching load proportionally. The modulation of the
compressor is possible through the unique feature called
axial compliance. This allows the compressor to operate
in two stages – the loaded and unloaded state. AES Series
600 – 1500 scfm models feature an external solenoid valve
that connects the modulation chamber on the top of the
compressor with the suction side. AES Series 1750 and
2000 scfm models, the components are integrated into the
compressor housing. When the solenoid valve is energized,
suction gases causes the top scroll to axially separate. When
the scrolls are separated, the compression of the gas is
interrupted.
When the compressor is unloaded the motor still rotates
at the normal speed, however no work is being performed.
Electrical consumption is reduced to approximately 10% of
full load conditions.
A cycle time is comprised of one loaded state time and
one unloaded state time. The duration of these states is
determined by a closed loop controller, which monitors
the temperature of the evaporator. The controller is set to
have a cycle time of 10 seconds. The percentage of loaded
vs. unloaded determines the capacity of the refrigeration
system. For example, if the loaded state is 5 seconds
and the unloaded state is 5 seconds, the compressor
modulation is equal to 50% output. If the compressor
loaded state time is 8 seconds and the unloaded state is 2
seconds, the compressor modulation is 80%. The capacity
is the time average of the loaded state and the unloaded
state. By varying the states the compressor is able to have
any refrigeration capacity between 10% and 100%.
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Air Load %
Energy Consumption %
Key
AES Series
Non-Cycling
FIGURE 2-4: Graphic of Digital Scroll Operation. The top
view shows the compressor loaded with compression taking
place. The bottom view shows the scrolls separated and no
compression taking place.
FIGURE 2-5: Energy Consumption vs Inlet Load. Graph shows
difference in energy consumption between general, non-cycling
refrigerated air dryers and AES Series Energy Saving, Digital
Scroll refrigerated air dryers.