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Changing the suction height affects pumped volume. The higher the suction height is, the smaller the pumped volume becomes. The lower the suction height is, the larger the pumped volume becomes. 
The table below shows an example of measured changes in pumped volume resulting from changes in suction height.

Model number used: NRP-500P
Measurement conditions: 
The pumped volume is set at 500mm3 when the suction height is 500mm.
(Other than the conditions specified below, the measurements follow the standard test conditions.)  

Experimental data of pumped volume versus suction height

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