2
Assembly of sensor, cap, tape, and tip
Calibrating the Sensor
It may not be necessary to perform a calibration when using Go Direct Ethanol
Vapor. If your experiment or application is evaluating the rate of ethanol
production, such as determining fermentation rates with yeast, or the relative
change in ethanol concentration, then the stored calibration works well.
For quantitative analysis of ethanol samples, it is best to use a two-point
calibration to improve accuracy. The two points you choose for your calibration
will depend on the expected amount of ethanol in your sample. For best results
at low concentrations (0.1–1%), calibrate using 1% and 0.1% ethanol. For best
results at high concentrations (1.0–3.0%), calibrate using 3.0% and 1% ethanol.
If you are measuring an intermediate range you can also calibrate using 0.2%
and 2.0% ethanol.
To calibrate the sensor in Graphical Analysis, complete the following steps.
1. Click or tap the sensor meter to view sensor options.
2. Select Calibrate and follow the applicable prompts on the Calibrate Sensor
screen.
Once you have calibrated your Go Direct Ethanol Vapor, the calibration is
automatically stored to the sensor and will be used each time you connect to
your device. You can always choose to restore factory defaults if you feel the
custom calibration is invalid.
To restore factory defaults in Graphical Analysis, complete the following steps.
1. Click or tap the live readouts meter and choose Calibrate.
2. Click or tap Reset Calibration.
A window will appear warning you that you are about to reset the calibration.
Choose Reset Calibration.
Making Ethanol Standards for Calibration
To make solutions for the ethanol calibration, you will need to dilute fresh,
stock ethanol to the appropriate concentration. Denatured ethanol or non-
denatured, grain ethanol may be used. Ethanol that is 70% is more stable than
95%. For the most accurate results, use a volumetric flask to make the standards.
Use the following equation to guide you:
Powering the Sensor
Turning on the sensor
Press button once. Red LED indicator flashes
when unit is on.
Putting the sensor in sleep
mode
Press and hold button for more than three
seconds to put into sleep mode. Red LED
indicator stops flashing when sleeping.
Connecting the Sensor
See the following link for up-to-date connection information:
www.vernier.com/start/gdx-etoh
Connected and charging
Blue and Green LED solid when sensor is con-
nected to Graphical Analysis via USB and unit
is charging. (Green LED is obscured by the blue
one.)
Connected
Green LED solid when sensor is connected to
Graphical Analysis via USB and the unit is fully
charged. Green LED flashing when sensor is con-
nected to Graphical Analysis via Bluetooth wire-
less technology.
Charging via USB,
connected via Bluetooth
wireless technology
Blue LED is solid and green LED is flashing, but
the green flashing LED looks white because it is
overwhelmed by the blue.
Identifying the Sensor
When two or more sensors are connected, the sensors can be identified by
tapping or clicking Identify in Sensor Information.
Using the Product
1. Remove the tip of the cap from the sensor. Discard the tissue paper covering
the cap (first use only).
2. Cut a 1.5 centimeter piece of plumber’s tape (included).
3. Cover the cap entirely with the tape and inspect the tape for wrinkles or
gaps.
4. Place the tip over the tape and verify that it is secure before proceeding.
5. Connect the probe following the steps in the Getting Started section of this
user manual.
Note:
Remove the tape from the cap at the end of the experiment. For best
results, use a new piece of tape each day the sensor is used.