Sullair LS-200 Operator's Manual And Parts List page 21

Figure 2-3C Control System with Electro-Mechanical Controller
being used. At approximately 10 psig (0.7 bar) air
line over-pressure, the control system will automat-
ically blow down the compressor and greatly reduce
the unload power consumption. The Control
System consists of an inlet valve, (located on the
compressor air inlet), blowdown valve, solenoid
valve, pressure switch, and a pressure regula-
tor. The functional descriptions of the Control
System are given below in four distinct phases of
compressor operation. The following guidelines
apply to all 200 Series compressors. For explana-
tory purposes this description will apply to a com-
pressor with an operating pressure range of 100 to
DESCRIPTION
110 psig (6.9 to 7.6 bar). A compressor with any
other pressure range would operate in the same
manner excepting stated pressures.
START - 0 TO 50 PSIG (0 TO 3.5 BAR)
When the compressor START button is depressed,
the sump pressure will quickly rise from 0 to 50 psig
(0 to 3.5 bar). During this period both the pressure
regulator and the solenoid valve are closed, the
inlet valve is fully open due to inlet air flow, and the
compressor pumps at full rated capacity. The rising
compressor air pressure is isolated from the service
line in this phase by the minimum pressure valve,
set at approximately 50 psig (3.5 bar).
Section 2
13