Capacity Control System, Functional Description - Sullair 125 User Manual

SECTION 2
WARNING
DO NOT remove caps, plugs and/or other
components when the compressor is run-
ning or pressurized. Stop the compressor
and relieve all internal pressure before
removing these items.
2.6 CAPACITY CONTROL
SYSTEM, FUNCTIONAL
DESCRIPTION
Refer to Figure 2-3 or Figure 2-4. The purpose of the
control system is to regulate the amount of air intake
and match it to the demand (required output) on the
compressor. The control system consists of a
pressure regulating valve(s), air inlet valve, system
blowdown valve, engine speed control, and tubing
connecting the various
compressor and engine. The functional descriptions
of the control system are described by relating them
1. Receiver/Tank
2. Minimum Pressure/Check Valve
3. Internal Air/Oil Separator Element
components of the
Figure 2-3: Compressor Discharge System
125, 130, 49HP AND 185 USER MANUAL
to four distinct phases of operation. They apply to
any control system with the exception of those with
specified pressures which
pressure requirements. The given values apply to a
compressor with an operating pressure range of 100
to 110 psig (6.9 to 7.6 bar).
S – 0 T 40
TART O PSIG
When the compressor is started, the sump pressure
quickly rises from 0 to 40 psig (0 to 2.8 bar). During
this period the pressure regulator valve is inactive. At
this pressure range the idle warm-up control keeps
the inlet valve closed for engine idle operation. Within
30 seconds of starting the compressor (the
instrument panel annunciator light goes off after 30
seconds) turn the handle of the warm-up selector
valve (located on the instrument panel) from the
START to the RUN position. The inlet valve is fully
open due to inlet pressure, and the compressor
operates at full capacity. When the compressor
operates at full capacity, the engine runs at full
speed.
4. Compressor Unit
5. Service Air Outlets
are dependent on
(0 T 2.8 B )
O AR
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