• Go Direct Colorimeter
• 15 polystyrene cuvettes and 15 plastic cuvette lids
• Micro USB Cable

Choose a platform below to see its compatibility requirements.

LabQuest

Interface	LabQuest App
LabQuest 3	Full support
LabQuest 2 (discontinued)	Full support 1
LabQuest (discontinued)	Incompatible

Compatibility Notes

1. Wireless connection of this sensor to a LabQuest 2 requires a Go Direct Bluetooth Adapter when used with some older LabQuest 2 models.

Computers

	Software
Interface	Graphical Analysis
No interface required	Full support 1
LabQuest 3	Full support 2
LabQuest 2 (discontinued)	Full support 2 3

Compatibility Notes

1. For Bluetooth^® connectivity, only computers running Windows 10 or Mac OS X 10.10 or newer are supported. The computer must also have a compatible Bluetooth 4.0⁺ radio.
2. Connect this sensor directly to a computer or Chromebook via a USB or wireless Bluetooth^® connection for best results. Alternatively, this sensor is fully supported when used with LabQuest 2 or LabQuest 3 when the LabQuest is connected to a computer or Chromebook via Wireless Data Sharing.
3. Wireless connection of this sensor to a LabQuest 2 requires a Go Direct Bluetooth Adapter when used with some older LabQuest 2 models.

Chromebook

	Software
Interface	Graphical Analysis
No interface required	Full support
LabQuest 3	Full support 1
LabQuest 2 (discontinued)	Full support 1 2

Compatibility Notes

1. Connect this sensor directly to a computer or Chromebook via a USB or wireless Bluetooth^® connection for best results. Alternatively, this sensor is fully supported when used with LabQuest 2 or LabQuest 3 when the LabQuest is connected to a computer or Chromebook via Wireless Data Sharing.
2. Wireless connection of this sensor to a LabQuest 2 requires a Go Direct Bluetooth Adapter when used with some older LabQuest 2 models.

iOS

	Software
Interface	Graphical Analysis	Graphical Analysis GW
No interface required	Full support	Full support
LabQuest 3	Full support 1 2	Full support 1 2
LabQuest 2 (discontinued)	Full support 1 2 3	Full support 1 2 3

Compatibility Notes

1. Connect this sensor directly to a supported mobile device via a wireless Bluetooth^® connection for best results.
2. iOS and Android^™ devices can only connect to LabQuest 2 or LabQuest 3 via Wireless Data Sharing.
3. Wireless connection of this sensor to a LabQuest 2 requires a Go Direct Bluetooth Adapter when used with some older LabQuest 2 models.

Android

	Software
Interface	Graphical Analysis	Graphical Analysis GW
No interface required	Full support	Incompatible
LabQuest 3	Full support 1 2	Full support 1
LabQuest 2 (discontinued)	Full support 1 2 3	Full support 1 3

Compatibility Notes

1. iOS and Android^™ devices can only connect to LabQuest 2 or LabQuest 3 via Wireless Data Sharing.
2. Connect this sensor directly to a supported mobile device via a wireless Bluetooth^® connection for best results.
3. Wireless connection of this sensor to a LabQuest 2 requires a Go Direct Bluetooth Adapter when used with some older LabQuest 2 models.

Python

	Software
Interface	Python
No interface required	Full support

Javascript

	Software
Interface	Javascript
No interface required	Full support 1

Compatibility Notes

1. A wireless Bluetooth^® connection can be made with Go Direct sensors on any platform running a browser with WebBluetooth support. However, only a few operating systems have been tested and testing has been limited.

LabVIEW

	Software
Interface	NI LabVIEW
No interface required	Full support 1

Compatibility Notes

1. For Bluetooth^® connectivity, only computers running Windows 10 or Mac OS X 10.10 or newer are supported. The computer must also have a compatible Bluetooth 4.0⁺ radio.

Connect the Go Direct Colorimeter to the included USB Charging Cable and any USB device for two hours.

You can also charge up to eight Go Direct Go Direct Colorimeters using our Go Direct Charge Station, sold separately (order code: GDX-CRG). An LED on each Go Direct Colorimeter indicates charging status.

Charging	Orange LED next to the battery icon is solid while the sensor is charging.
Fully charged	Green LED next to the battery icon is solid when the sensor is fully charged.

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.

See the following link for up-to-date connection information:

www.vernier.com/start/gdx-col

Connecting via Bluetooth

Ready to connect	Red LED next to the Bluetooth icon flashes when sensor is awake and ready to connect.
Connected	Green LED next to the Bluetooth icon flashes when sensor is connected via Bluetooth.

Connecting via USB

Connected and charging	Orange LED next to the battery icon is solid when the sensor is connected to Graphical Analysis via USB and the unit is charging. LED next to Bluetooth icon is off.
Connected, fully charged	Green LED next to the battery icon is solid when the sensor is connected to Graphical Analysis via USB and fully charged. LED next to Bluetooth icon is off.
Charging via USB, connected via Bluetooth	Orange LED next to the battery icon is solid when the sensor is charging. Green LED next to the Bluetooth icon flashes.

Connect the sensor following the steps in the Getting Started section of this user manual. After connecting the sensor, the following steps must be completed prior to starting data collection.

1. Press the < or > button on the Colorimeter to select the correct wavelength for your experiment (430 nm, 470 nm, 565 nm, or 635 nm).
2. Allow the Colorimeter to warm up for about five minutes before calibrating.
3. Calibrate the Colorimeter.
   1. Slide the lid of the Colorimeter open to reveal the cuvette slot.
   2. Insert a cuvette, filled with distilled water or other solvent used to prepare your solutions, for your calibration blank (100% transmittance or 0 absorbance).
      Important: Line up one of the clear sides of the cuvette with the arrow at the right side of the cuvette slot. Slide the Colorimeter lid closed.
   3. Press the CAL button on the Colorimeter to begin the calibration process. Release the CAL button when the red LED begins to flash.
   4. When the red LED stops flashing, the calibration is complete. The absorbance reading should be very close to 0.000 (100%T).
   5. Remove the blank cuvette from the Colorimeter.
4. Continue with data collection.

Calibration is required for use. See the Using the Product section for instructions.

Colorimeter range	0 to 3 (absorbance) (0 to 100% T)
Useful range	0.05 to 1.0 absorbance (90% to 10% T)
Wavelengths	430 nm, 470 nm, 565 nm, 635 nm

Battery Information

Go Direct Colorimeter contains a small lithium-ion battery. The system is designed to consume very little power and not put heavy demands on the battery. Although the battery is warranted for one year, the expected battery life should be several years. Replacement batteries are available from Vernier (order code: GDX-BAT-300).

Storage and Maintenance

To store Go Direct Colorimeter for extended periods of time, put the device in sleep mode by holding the button down for at least three seconds. The red LED will stop flashing to show that the unit is in sleep mode. Over several months, the battery will discharge but will not be damaged. After such storage, charge the device for a few hours, and the unit will be ready to go.

Exposing the battery to temperatures over 35°C (95°F) will reduce its lifespan. If possible, store the device in an area that is not exposed to temperature extremes.

Water Resistance

Go Direct Colorimeter is not water resistant and should never be immersed in water.

If water gets into the device, immediately power the unit down (press and hold the power button for more than three seconds). Disconnect the sensor and charging cable, and remove the battery. Allow the device to dry thoroughly before attempting to use the device again. Do not attempt to dry using an external heat source.

Light from an LED light source passes through a cuvette containing a solution sample. Some of the incoming light is absorbed by the solution. As a result, light of a lower intensity strikes a photodiode.

Here are some tips for best data-collection practices:

• Allow the Colorimeter to warm up for about 5 minutes before calibrating.
• Fill a cuvette two-thirds to three-fourths full with liquid, including the calibration blank, so that the light travels through the liquid reliably.
• After filling a cuvette with liquid, seal the cuvette with a cap to prevent spills.
• Make sure to place a cuvette in the Colorimeter so the path of the light source travels through the clear sides of the cuvette. An arrow to the right of the cuvette slot shows the light path.
• For best results, use one cuvette to make all your measurements for a given experiment.
• If you calibrate a Colorimeter and then change the wavelength, calibrate the Colorimeter again to ensure the proper identification of the new wavelength.

For best results, a sample's absorbance or transmittance values should fall within these ranges:

• percent transmittance:10–90%
• absorbance: 0.05–1.0

Beer’s law experiment results begin to lose their linearity at absorbance values above 1.0 (percent transmittance values less than 10%). If you have a solution that transmits such a low level of light, consider diluting the solution so that it falls within this range.

If you have followed the troubleshooting steps and are still having trouble with your Go Direct Colorimeter, contact Vernier Technical Support at support@vernier.com or call 888-837-6437. Support specialists will work with you to determine if the unit needs to be sent in for repair. At that time, a Return Merchandise Authorization (RMA) number will be issued and instructions will be communicated on how to return the unit for repair.

Item	Order Code
Micro USB Cable	CB-USB-MICRO
USB-C to Micro USB cable	CB-USB-C-MICRO
Go Direct 300 mAh Replacement Battery	GDX-BAT-300
Plastic Cuvettes (Visible Range)	CUV