Continuous Regulating System - Atlas Copco XAHS 146 Dd S3B APP Instruction Manual

CONTINUOUS REGULATING SYSTEM

(RV)
(AR)
(UA)
(BOV)
(CE)
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The system comprises:
RV Regulating valve
UA Unloader assembly
The compressor is provided with a continuous
regulating system. This system is provided with a
blow-down valve, which is integrated in the unloader
assembly (UA). The valve is closed during operation
by air receiver pressure and opens by air receiver
pressure via the compressor element when the
compressor is stopped.
When the air consumption increases, the air receiver
pressure will decrease and vice versa. This receiver
pressure variation is sensed by the regulating valve
which, by means of control air to the unloader,
matches the air output to the air consumption. The air
receiver pressure is maintained between the pre-
selected working pressure and the corresponding
unloading pressure.
When starting the compressor, the unloader valve
(UV) is kept open by spring force, the engine runs at
maximum speed. The compressor element (CE) takes
in air and pressure builds up inside the receiver (AR).
The air output is controlled from maximum output
(100%) to no output (0%) by:
1. Speed control of the engine between maximum
load speed and unloading speed (the output of a
screw compressor is proportional to the rotating
speed).
2. Air inlet throttling.
3. Blow off valve (BOV).