Pilot Air PAC Series Users Maintenance And Spare Parts Manual page 16

OPERATING MODE
•
During first start-up, motor is
started and "star" powered. During
this phase compressor starts slowly,
solenoid valve is closed and suction
regulator (2) is closed.
•
The compressor is kept under
these conditions for about 6
seconds.
•
This time over, motor is "delta"
powered. Solenoid valve is powered
and enables suction regulator (2)
opening. The regulator sucks in air
through filter (1).
•
During this phase compressor is
working at peak rpm and starts
compressing air inside oil separator
tank (5), through tube (4).
•
Compressed air cannot escape
through the min. pressure valve (7),
which is set at 3÷4 bar.
•
Compressed air compresses oil
inside tank (5) and causes it to flow
through tube (8) to the radiator (9).
Cooled oil is returned to filter (11)
through tube (10).
•
From filter (11), oil reaches compressor (3) through tube (12). Oil is mixed with sucked air to form an
air/oil mixture that provides sealing and lubrication of compressor moving parts.
•
The air/oil mixture goes back to tank (5), where air and oil are first separated by centrifugation and
then by the oil separator filter (6).
•
As a result, tank (5) will deliver air only to air radiator (9) through tube (13). Air is then conveyed to
mains through a cut-off cock.
•
Min. pressure valve (7) serves also as a check valve.
•
Compressor delivers compressed air to outer air tank.
•
Tank inner pressure increases until reaching max. calibration value.
•
Once max. value is reached, pressure gauge starts timer and powers off solenoid valve of regulator
(2).
•
Regulator (2) closes and compressor stops compressing and starts idling.
•
Timer continues counting until reaching set value and, if pressure is unchanged, stops the electric
motor. If pressure drops to minimum value set on controller, solenoid valve is powered and opens
before timer counting is over.
•
Regulator (2) opens and compressor operates under normal load; timer is reset.
•
This cycle is automatically repeated.
16 | P a g e
Start-Up and Operation
PLUS 56-75-Cod.197DD8805