Ingersoll-Rand EP 60, Варианты руководства оператора/инструкции по эксплуатации

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4.7 COMPRESSOR CONTROL SYSTEM
The Intellisys® controls the various operating modes
of the compressor, monitors key compressor operating
parameters, and shuts the compressor down in the
case of an operating problem. The control system has
customer adjustable inputs as described in the
Intellisys® section 3.0. The compressor control system
has the following standard features.
• Automatic Unloaded Start.
• On/Off Line Capacity Control.
• Unloaded Stop.
• Automatic Start/Stop.
• Compressor Fault Warning.
• Compressor Fault Alarm Shutdown.
The following paragraphs provide a description of the
standard features. Please also refer to the flow
schematic in section 7.0.
Automatic Unloaded Start
Pushing the start button signals the Intellisys® to
engage the starter coils and opens the oil stop valve
(5SV). The compressor will always start in the
unloaded mode, with the inlet valve in the closed
position and the blowdown valve open to vent the
pressure from the separator tank. The unloaded start
ensures that the compressor has a low starting torque
requirement and that proper oil flow is established
before the compressor loads. Compressors with full
voltage starters will not load for seven seconds after
the starter button is pressed. Compressors with
optional star-delta starters will not load until two
seconds after star-delta transition. If system pressure
is below the on line set point pressure, the
compressor will automatically load at this time. Press
the load/unload button to prevent the compressor from
loading.
Adjustment Of Unloaded Sump Pressure.
During unloaded operation, the inlet valve must allow
some air flow past it to maintain sump pressure for
proper lubricant flow. This air is compressed by the
compression module and vented through the blowdown
valve (3SV). By adjusting the closed position of the inlet
valve plate, the unloaded sump pressure can be varied.
The unloaded sump pressure is set at the factory and
should not need adjustment under most circumstances.
If adjustment is required use the following procedure.
Tools Required
• 1/2" open end wrench.
• 9/16" open end wrench.
• Loctite® 242 or equivalent.
With the compressor shut down remove the nut that
fastens the inlet valve pivot anchor to the bracket on the
inlet valve. Apply Loctite® 242 or equivalent to threads
on spacer and loosely install nut. Start compressor and
press the unload button so that the compressor will not
load. Use the display select button to indicate sump
pressure on the display. Move the position of the pivot
anchor to alter the sump pressure until the sump
pressure is between 25-35 psig (1.7-2.4 bar). Moving
the pivot towards the inlet valve will raise the sump
pressure. Moving the pivot away from the inlet valve will
lower the sump pressure. Once the position is correct,
fully tighten the nut.
On/Off Line Control
The standard control system provides for either full
compressor capacity flow or zero flow based on the
system pressure. If the system pressure falls below
the on line set point, the Intellisys® energizes the
load/unload solenoid (1SV) and the blowdown
solenoid (3SV). This causes the inlet valve to open
and the blowdown valve to close. Compressed air
flows into the system.
If system pressure reaches the off line setting, the
compressor unloads to minimize power demands. The
Intellisys® de-energizes the load/unload solenoid
(1SV) and the blowdown solenoid (3SV). This causes
the inlet valve to close and vents the separator tank.
The minimum pressure check valve (MPCV) closes to
prevent back flow from the compressed air system.
The compressor operates at minimum power until the
system pressure falls to the on-line pressure setting.
Delay Load Time
This is the amount of time the line pressure must
remain below the on line set point before the
compressor will load or start (if the unit was stopped
due to an auto start/stop situation). This timer will not
delay loading after a start or if the time is set to zero.
The delay load time feature is useful if the compressor
is operating as a backup to another compressor and
is normally stopped in auto start/stop mode. The delay
load time prevents the compressor from starting and
loading if the system air pressure momentarily drops
below the on line setting of the backup compressor. If
no delay is desired the delay load time setting should
be set to zero.