Tubing (Please see the figure of the tubing for the standard test.)
> PTFE tube (I.D. x O.D. = 2 x 3mm) is used for the tubing.
> The length of the tubing is set at 1000mm on the inlet side and at 100mm on the outlet side.
> A reservoir tank is placed below the metering pump. The height from the liquid surface to the inlet is set at 500mm.
> The height of the tip of the outlet tube is set at 0mm from the horizontal plane.
>  Depending on the set pumped volume, a nozzle is installed at the end of the tube to reduce the diameter of the tube. (*)
(* If the discharge of the metering pump is set low and the diameter of the tube is large, the pump may not discharge liquid in each cycle due to the influence of surface tension etc. )

Operating Conditions
> Ambient temperature and fluid temperature: 
  The temperature is maintained at room temperature (20°C).
> The rated voltage is applied. It is operated with the maximum operating frequency and duty cycle of 50%.
  Example: In the case of NRP-500P, it is operated with the operation frequency of 2Hz  (ON: 250ms, OFF: 250ms).


Measurement Conditions
> The liquid used for this measurement is water.
> The metering pump is continuously operated until the inside of the metering pump and the tubing are filled with the fluid before the measurements are commenced.
> The pumped volume of 10 cycles is measured by gravimetry after which the pumped volume per cycle is calculated.


Measuring the accuracy of the discharge
> The pumped volume of 10 cycles is measured ten times and the average is calculated.
> The difference between the maximum and minimum values of the ten cycles and the average is determined. The repeatability of pumped volume is expressed in percentage variation from the average.