Ingersoll-Rand VHP40RMD, Руководство по эксплуатации и техническому обслуживанию

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36 23221138 (12-07) Rev A
Unloader Pressure Adjustment
• The pressure regulation is accomplished by adjustment available on the unloader
valve. The factory setting is 175 psig, but the end user if desired can lower this.
• At the set pressure, the unloader opens to divert flow from the air pump overboard.
At the same time, pressure to the engine throttle control air cylinder is provided to
bring the engine to idle speed.
• When the unit is unloaded and the discharge pressure reduces as service air is
consumed, the pressure reduces to a point that the unloader valve returns to the load
sense. This closes the diverter valve and re-establishes the airflow through the
normal discharge port. The pressure at which this occurs is approximately 30 psi less
than the unload pressure, and this regulation range is not reset table by the end user.
• To reset the unload pressure, loosen the lock nut that secures the adjusting screw
just under the hand unloader toggle. Turn the adjusting screw outward (ccw) to
reduce the pressure. Turn the screw inward (cw) to increase pressure.
CAUTION
!
Do not set the pressure at above 175 psig.
• Adjustments can be made with the unit off, loaded, or unloaded, but must be checked
by allowing the unit to unload and noting the pressure at which this occurs. If
necessary, readjust and repeat until desired pressure is achieved.