Go Direct® Drop Counter (GDX-DC)
Specifications and User Guide

-Primary Test: If your Drop Counter is not counting drops, check the alignment of the sensor beneath the tip of the reservoir or buret. Adjust the Reagent Reservoir so that the drop passes closer to the center of the slot.
-Secondary Test: The Drop Counter works best when the drops fall at a rate of 2 seconds per drop or slower.

-If you cannot get it to count drops, use your finger or a pen to break the beam and see if this registers in the software.

Do you have a drop counter?
How can I improve my results with the Drop Counter?
Why is the Drop Counter calibration lost?
I want to use my drop counter to get a graph of drops per second.

-Calibrate? Not always. The sensor is set to use a default calibration of 28 drops/mL.
Graphical Analysis, Graphical Analysis Pro, and LabQuest App (version 2.8.4 or newer) support calibration with the following instructions:

Go Direct Drop Counter Calibration in Graphical Analysis

To perform your own drops-per-mL calibration. View the video above. The steps are here:
a. Place a 10 mL graduated cylinder below the slot of the Drop Counter.
b. Fill the reagent reservoir about 3/4 full with the titrant solution.
c. Choose to calibrate the Drop Counter in your data-collection program.
d. Open the bottom 2-way (on-off) valve to begin releasing drops through the Drop Counter.
e. Release drops until there are 9-10 mL of liquid in the graduated cylinder.
f. Close the bottom valve to stop the drops.
g. Type the exact volume, to the nearest 0.1 mL, of liquid in the graduated cylinder in the Volume (mL) box of the Calibrate drops dialog box.
h. Choose to stop the calibration routine of your program.
i. The number of drops/mL will be displayed.
j. You can now continue with the titration.

Note: You may manually enter a drops/mL ratio that was done from a previous calibration.

If the sensor can be turned on when connected by USB but not when disconnected from USB, the battery either needs charging or has reached its end of life and can no longer hold a charge. First, try charging the sensor for several hours. If the sensor still won’t turn on when disconnected from USB, the battery has likely reached its end of life. If you intend to use this sensor wirelessly, the battery will need to be replaced. The rechargeable battery in this sensor is covered by a one year warranty but should last two to five years in typical use.

Microstirrer (MSTIR)
Stir Station (STIR)
Go Direct® pH Sensor (GDX-PH)
Reagent Reservoir, 2 Valves, and Tip (VDC-RR)
Stopper Stem (PS-STEM)
Plastic 2-Way Valve (PS-2WAY)
Micro USB Cable (CB-USB-MICRO)