Regulating System - Comprag A9008 Bedienungsanleitung

2.5

Regulating system

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4
3
5
2
6
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Fig. 2.5 Regulating system
The system is controlled by an electronic controller pro-Log (4) which keeps the net
pressure within programmable pressure limits by automatically loading and unloading the
compressor in relation to air consumption.
Unloading:
If air consumption is less than the air delivered by the compressor, the net pressure increas-
es. When the net pressure reaches the upper limit of working pressure (unloading pressure),
the solenoid valve (6) is de-energized. The damper (2) of the intake valve (1) closes the air
inlet opening by a spring force:
1. The control pressure present in the chambers of the loading plunger (3) and the unload-
ing valve (5) is vented into the atmosphere via the solenoid valve (6).
2. The loading plunger (3) moves forwards and causes the intake valve (1) to close the air
inlet opening.
3. The unloading valve (5) is opened by the air-oil separation tank pressure. The pressure
from the air-oil separation tank (7) is released towards the air inlet.
4. The pressure is stabilized at a low value, air output is stopped (0 %) and the compressor
runs unloaded.
Loading:
When the net pressure decreases to the loading pressure, the solenoid valve (6) is energized:
1. The control pressure is fed from the air-oil separation tank (7) via the solenoid valve (6) to
the loading plunger (3) and the unloading valve (5).
2. The unloading valve (5) closes the air blow-off opening. The loading plunger (3) moves
backwards and causes the intake valve (1) to open fully.
Air output is resumed (100 %), and the compressor runs loaded.
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COMPRAG Screw air compressor A-Series