Quincy Compressor QGS 90, Инструкция

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Loading
When the net pressure is below the loading pressure, solenoid valve (Y1) is energised. Results:
• The space above unloading valve/blow-off valve (UV) is connected with the oil separator
tank pressure (1) via the solenoid valve.
• Unloading valve/blow-off valve (UV) moves downwards, closing off the connection to
channels (2) and (3).
• Underpressure from the compressor element causes loading plunger (LP) to move
downwards and inlet valve (IV) to open fully.
Air delivery is 100%, the compressor runs loaded.
Unloading
If the air consumption is less than the air output of the compressor, the net pressure increases.
When the net pressure reaches the unloading pressure, solenoid valve (Y1) is de-energised.
Results:
• The pressure above unloading valve/blow-off valve (UV) is released to atmosphere and the
space above valve (UV) is no longer in connection with the oil separator tank pressure (1).
• Unloading valve/blow-off valve (UV) moves upwards, connecting the oil separator tank
pressure (1) with channels (2) and (3).
• The pressure in channel (2) causes the loading plunger (LP) to move upwards, causing inlet
valve (IV) to close, while the pressure is gradually released to atmosphere.
• The pressure in the separator tank stabilises at low value. A small amount of air is kept
drawn in to guarantee a minimal pressure, required for lubrication during unloaded
operation.
Air output is stopped, the compressor runs unloaded.
2.4 Electrical system
General
On units powered by a frequency converter, wait 10 minutes before starting any electrical
repair.
Electrical components
The electrical system comprises the following components:
Instruction book
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