The pump <em>increases the hydraulic pressure to the nominal value required by the system.
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<u>Variable displacement pump</u>: <em>A variable displacement pump has a fluid outlet that varies to meet the system's pressure demands. The pump output is automatically changed to a compensating pump inside the pump.
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Variable displacement pumps are independent of the number of revolutions per minute of the pump as the amount of liquid displaced depends on the needs of the system.
