Updated 1-8-07

Fluid Standpipe Calibration Procedure

Flow Meter

  1. In your lab notebook, create the following chart so that it is big enough for the number of trials you plan on performing:

Table 1: Calibration Chart

Trial / Valve Control Voltage (V) / Time (sec) / Water (mL)
  1. Plug in power cord and turn the unit on.
  2. Attach military connector to appropriate side of lab station and turn on SCXI chassis.
  3. Connect the calibration hose directly to the exit of the flow meter. This is just a straight hose with a snap fitting on one end.
  4. Remove the calibration plug on the top of the water tank (see Figure 6) and put the red funnel in the hole.
  5. Place the end of the calibration hose into the funnel
  6. Start the VI by pressing the run arrow in the left hand corner. And set the valve control to 2 V.
  7. Move the tube from the funnel to the graduated cylinder and use your stop watch to see how long it takes to fill the graduated cylinder to about 200 mL. Record the exact time and volume in your notebook.
  8. Pour the water from the graduated cylinder back into the box.
  9. Do a few trials with the same valve control setting.
  10. Change the valve control setting and repeat steps 6-9.
  11. Set valve control to zero.
  12. Save your data using the Stop and Save Data button at the bottom of the VI.
  13. Average the flow rate voltage at each valve control setting and compare to the measured flow rate to get your calibration curve.
  14. Input your new equation into the LabView program and save.

Figure 6: Location of Plug on top of Water Box

Height/Pressure Sensor

  1. Attach the red hose to the snap fitting at the base of the standpipe and assemble standpipe as directed in main procedure.
  2. Make sure the red valve is open to the water tank (The black arrow is pointed at yellow).
  3. Open the Fluid Standpipe.vi and press run in the upper left hand corner.
  4. Set your valve control so the standpipe is partially filled.
  5. Open the calibration plug on top of the water tank.
  6. To eliminate any air bubbles that might distort your data, remove the tube from the pressure sensor and quickly move it to the hole in the water tank. You will probably spill some water but can mitigate this by covering the spout with your thumb while transferring the hose. Allow all bubbles to escape and then return the hose to the pressure sensor. Use sponge to clean any spills.
  7. Set your valve control to 2 and wait for the standpipe to reach steady state. Measure the height from the bottom of the o-ring at the base of the standpipe using your ruler. Record the height and the level transducer voltage in your notebook.
  8. Repeat step 8 for various valve control settings.
  9. Set the valve control to zero.
  10. Follow clean up procedure as outlined in the main procedure.

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