Drain Valve: At the base of the air tank to drain
condensation at the end of each use.
ON/AUTO-OFF Switch: Turn this switch ON to pro-
vide automatic power to the pressure switch and OFF
to remove power.
Air Intake Filter: This filter is designed to clean air
coming into the pump. This filter must always be clean
and ventilation openings free from obstructions. See
"Maintenance".
Air Compressor Pump: In two stage compressors, air
is first compressed to an intermediate pressure in the
large bore cylinder, and after passing through an inter-
cooler, the air is further compressed to a higher pres-
sure in the smaller bore cylinder. This process contin-
ues until the air tank pressure reaches the factory set
cutoff pressure. At that point the pressure switch shuts
the electric motor off.
Check Valve: When the air compressor is operating,
the check valve is "open", allowing compressed air to
enter the air tank. When the air compressor reaches
"cut-out" pressure, the check valve "closes", allowing
air pressure to remain inside the air tank.
Pressure Release Valve: The pressure release valve
located on the side of the pressure switch, is designed
to automatically release compressed air from the com-
pressor head and the outlet tube when the air compres-
sor reaches "cut-out" pressure or is shut off. If the air
is not released, the motor will try to start, but will be
unable to. The pressure release valve allows the motor
MGP-LN1080H2-1A
Rev. 1
3/13/00
DESCRIPTION OF OPERATION
8—ENG
to restart freely. When the motor stops running, air will
be heard escaping from the valve for a few seconds. No
air should be heard leaking when the motor is running.
Pressure Switch: The pressure switch automatically
starts the motor when the air tank pressure drops below
the factory set "cut-in" pressure. It stops the motor
when the air tank pressure reaches the factory set "cut-
out" pressure.
Shut-off Valve: Turn the knob counterclockwise to
open the valve and clockwise to close.
Air Tank Safety Valve: If the pressure switch does
not shut off the air compressor at its cut-out pressure
setting, the safety valve will protect against high pres-
sure by "popping off" at its factory set pressure (slightly
higher than the pressure switch cut-out setting).
Aftercooler Safety Valve: On two stage compressor
units, safety valve is provided to prevent over-pres-
surization of the aftercooler. The valve will protect the
aftercooler by "popping off" at its factory set pressure.
Regulator: An air pressure regulator or a separate air
transformer which combines the functions of air regula-
tion and/or moisture and dirt removal is recommended
for most applications.
Tank Pressure Gauge: The tank pressure gauge
indicates the reserve air pressure in the tank. On outfits
with no pressure regulator, this is also the pressure
available at the air outlet.