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4. Design and functioning
22
Speed control operation
Speed is controlled using a software-implemented PI
regulator that adapts the RPMs according to the need
for compressed air.
The controller attempts to maintain the mains pressure
between the
CUT-OUT
POINT
and the
TARGET
PRESSURE
set in the control (see chapter 8.5.3).
Automatic operation
If the mains pressure achieves the preset maximum
value, then the electric motor (-3-) will have its
speed lowered in order to allow for the delivery
amount to adapt to the actual need for compressed
air.
If the motor has reached minimum speed and the
load-system pressure continues to rise, solenoid
valve (Y1 Fig. 4) is deenergized (closed). Reservoir
pressure is reduced to approx. 4 to 4.5 bar and the
pressure-maintenance valve (- 8 - Fig. 4) closes.
This way, no more compressed air will be supplied
to the mains.
If the mains pressure does not drop to the target
value within the programmed follow-up time, then
the system will shut down.
If the target value is achieved before the expiration
of the programmed motor follow-up time, then the
magnet valve (Y1 Fig. 4) will again be energized.
The system will then go into load runs.
4.6 Hood
(opening/closing)
The compressor is provided with a detachable plastic
hood that allows easy access to all parts that are
subject to servicing.
Opening / closing the hood (Fig. 5)
Open turnbuckle ( - 1 - Fig. 5)
Remove the hood ( - 2 - Fig. 5) and put it down at a
safe place
Close the hood in the reverse order
Fig. 5
1 Turnbuckle
2 Hood
Summary of Contents for L07
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