You can get your student force sensor back into working condition by adjusting the offset and the sensitivity to the original settings. This can be a little tricky, but if you follow the following process, the sensor can continue to function:

1. Set the program to read from the Student force sensor and when it asks you about calibration, choose “perform new.”
2. Place the sensor in the Zero-Force position (no mass hanging off of it).
3. Adjust the offset until you get a reading of 1.00 volts (If you are using a CBL, this will show on the CBL display, not the calculator).
4. Enter this as the Zero Force reading in the program.
4. For the second data point, hang a 1kg mass of the sensor, and adjust the Sensitivity screw until the voltage reads 0.02 Volts.
5. Enter this as your 9.8 newtons force reading.

Because the offset and the sensitivity settings affect one another, the sensor will probably not read zero newtons when you return it to the zero position. You will probably have to perform the above process 2 or three times before the sensor’s settings are returned to the factory settings. Once you have completed this, the sensor should work fine with the stored calibration that comes with the program.

For future reference – we do not recommend adjusting either the offset or the sensitivity settings on the sensor. The potentiometers often end up in positions such that a valid calibration can no longer be performed on the sensor.

Once the sensor is back to its original setting, we recommend putting a piece of tape over the the screws to discourage other people from undoing your work.