Air Inlet System, Functional Description - Sullair LS-200S Operator's Manual And Parts List

to 7.6 bar). During this range, the spiral valve
remains in the unload position.
UNLOAD MODE - IN EXCESS OF 110 PSIG (7.6
BAR)
Refer to Figures 2-5A
small amount or no air is being used, the service
line pressure continues to rise. When it exceeds
110 psig (7.6 bar), the Supervisor Control System
de-energizes the solenoid valve allowing line air
pressure to be supplied directly to close the inlet
valve. Simultaneously, the solenoid valve sends a
pneumatic signal to the blowdown valve. The blow-
down valve opens to the atmosphere, reducing the
sump pressure to approximately 15 to 20 psig (1.0
to 1.4 bar). The minimum pressure check valve pre-
vents line pressure from returning to the sump.
When the line pressure drops to the low setting
(cut-in pressure; usually 100 psig [6.9 bar] on low
pressure ["L"] compressors; 125 psig [8.6 bar] on
high pressure ["H"] compressors; 150 psig [10.3
bar] on ["HH"] compressors; and 175 psig [12.0
bar] ["XH"] . Supervisor energizes the solenoid
valve and allows the blowdown valve to close. The
re-energized solenoid valve again prevents line
pressure from reaching the inlet control valve.
Should the pressure begin to rise, the pressure reg-
ulator will resume its normal function as previously
described.
AUTOMATIC OPERATION
For applications with varied periods of time when
there are no air requirements, Supervisor's AUTO-
MATIC mode allows the compressor to shutdown
(time delayed) when no compressed air require-
ment is present and restart as compressed air is
needed.
2.7 AIR INLET SYSTEM, FUNCTIONAL DESCRIP-
TION
Refer to Figure 2-6. The Compressor Inlet System
consists of a dry-type air filter and an air inlet
valve.
and 2-5E. When a relatively
The poppet-type modulating air inlet valve directly
controls the amount of air intake to the compressor
in response to the operation of the pressure regula-
tor (see Modulating Mode, Section
valve also acts as a check valve, thus preventing
reverse rotation when the compressor is shut down.
"The Plastic Pipe Institute recommends against
the use of thermoplastic pipe to transport com-
pressed air or other compressed gases in
exposed above ground locations, e.g. in exposed
plant piping." (I)
PVC piping should not be used with Sullube. It
may affect the bond at cemented joints. Certain
other plastic materials may also be affected.
(I) Plastic Pipe Institute, Recommendation B,
Adopted January 19, 1972.
Figure 2-6 Air Inlet System
Section 2
DESCRIPTION
2.6). The inlet
17