Gardner Denver INTEGRA EFB99F - Section 4 Controls & Instrumentation; Control Package Overview and Operation; Pressure Relief Valve Function and Safety

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SECTION 4
CONTROLS & INSTRUMENTATION
GENERAL - The electrical controls on the compressor package are prewired and require only connection
to the building wiring. The standard package has all of the necessary controls for protection and fully
automatic operation.
OPERATION - The switch on the control box has an OFF position and an ON position. For normal
operation, leave the power connected to the compressor continuously, and use this selector switch. To
run the compressor, turn the switch to its ON position. To stop operation, turn the switch to its OFF
position. The OFF position also resets the controls after a power failure or other protective shutdowns.
When in the automatic mode, the controls operate the compressor. When air is used, the pressure in the
plant drops, and the compressor will start. After the compressor builds up the pressure, the compressor
unloads, and the motor runs at light load. If the plant calls again for more air, the compressor reloads. If
there is no demand, the motor stops after a time delay is completed.
The compressor drive motor and wiring are protected from overload by a thermal overload relay inside of
the control box. The control system features thermal protection for the compressor and oil separator, and
will stop the compressor if high temperatures or defective sensors are detected.
CAUTION
Damage will occur to the machine if it is repeatedly restarted after high
temperature stops operation. Find and correct the malfunction before resuming
operation.
Relief Valve - A pressure relief valve(s) is (are) installed in the final discharge line and set at the factory
to approximately 120% of the unit’s full load operating pressure for protection against overpressure.
Periodic checks should be made to ensure its proper operation.
WARNING
When the relief valve opens, a stream of high velocity air is released, resulting
in a high noise level and possible discharge of accumulated dirt or other debris.
Always wear eye and ear protection and stand clear of the discharge port when
testing the relief valve to prevent injury.
CAUTION
Never paint, lubricate or alter a relief valve. Do not plug vent or restrict
discharge.