Tech Note 473 Detail

Drop Counter Calibration Procedure

Affected Products:

PS-2117 PASPORT High Accuracy Drop Counter
CI-6499 ScienceWorkshop Drop Counter (High Accuracy)

Problem/Symptom:
What is the procedure for calibrating the Precision Drop Counter in DataStudio?

PASCO Solution:

Drop Counter Calibration (DataStudio weight method)

  1. Setup the Drop Counter as shown in Drop Counter Quick Start Card.
  2. Fill syringe or (preferably) a burette with distilled/deionized water.
  3. Weigh the beaker that you will use to catch drops to a resolution of 0.01g. Record this weight and then place the beaker under the Drop Counter.
  4. In the DataStudio program, click the Setup button to bring up the Experiment Setup window.
  5. Within the Calibrate Sensors window, select Drop Counter.
    NOTE: Once the Calibration window is open DataStudio is actively counting drops. If an error occurs while calibrating, such as allowing too many drops to fall at once, one must close the Calibration window by clicking on the Cancel button, and reopen the Calibration window to reset the counter.
  6. Slowly let at least 100 drops fall through the drop counter.
  7. Stop the flow of water and carefully remove the beaker.
  8. Weigh the beaker with the the water.
  9. Subtract the initial weight of the beaker from the new weight of the beaker to find the weight of the water.
  10. Given that the density of water is 1.0 g/ml find the volume (in ml) of water that passed through the drop counter. (For an more accurate value of the density of water, determine the temperature of the water used and determine the actual density of water at that temperature.)
  11. Type in the volume of water determined in the previous step into the Standard Value box located in the Calibrate Sensors window.
  12. Click OK button to accept the new calibration.
  13. In the Experiment Setup window, check Fluid Volume.

Drop Counter Calibration in DataStudio (volume method)

  1. Setup the Drop Counter as shown in Drop Counter Quick Start Card.
  2. Fill a calibrated burette with the titrant that you will be using in the experiment.
  3. Record the initial volume.
  4. In the DataStudio program, click the Setup button to bring up the Experiment Setup window.
  5. Within the Calibrate Sensors window, select Drop Counter.
    NOTE: Once the Calibrate Senors window is open DataStudio is actively counting drops. If an error occurs while calibrating, close and reopen the Calibrate Sensors window to reset the counter.
  6. Slowly let at least 100 drops fall through the drop counter.
  7. Record the final burette volume.
  8. Type the value of the difference in initial and final volumes into the Standard Value box located in the Calibrate Sensors window.
  9. Click OK button to accept the new calibration.
  10. In the Experiment Setup window, check Fluid Volume.

Drop Counter Calibration on the Xplorer GLX (volume method)

  1. Setup the Drop Counter as shown in Drop Counter Quick Start Card.
  2. Fill a calibrated burette with the titrant that you will be using in the experiment.
  3. Note the initial volume Vi on the burette.
  4. Go to the Home>Sensors menu.
    NOTE: Once the Calibration window is open DataStudio is actively counting drops. If an error occurs while calibrating, such as allowing too many drops to fall at once, one must close the Calibration window by clicking on the Cancel button (F2), and reopen the Calibration window to reset the counter.
  5. Set Fluid Volume to Visible.
  6. Go to the Sensors>Calibrate menu.
  7. Slowly let at least 100 drops fall through the drop counter.
  8. Press Read Pt 2, which will record the number of drops that have fallen.
  9. Record the final volume Vf of the burette.
  10. Type the value of the difference between the initial and final volumes Vf-Vi into the Pt 2 (drops) box.
  11. Click the OK button to accept the new calibration.

Creation Date: 02/25/2004
Last Modified: 04/6/2010
Mod Summary: