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5. 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 Section 9.5.3).
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 de-energized (closed).
Reservoir pressure is reduced to approx. 58 to
65 PSI 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.
5.6
Hood (opening/closing)
The compressor is provided with a detachable metal
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