Vernier Go Direct Surface Temperature User manual

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power button once. The LED will
blink red.
4. Launch Graphical Analysis or turn
on LabQuest.
5. If using Graphical Analysis, click
or tap Sensor Data Collection. If
using LabQuest, choose Wireless
Device Setup > Go Direct from the
Sensors menu.
6. Select your Go Direct sensor from
the list of Discovered Wireless
Devices. Your sensor's ID is located
near the barcode on the sensor. The
LED will blink green when it is
successfully connected.
7. Click or tap Done to enter data-
collection mode.
collect data.
Note: This sensor does not work with
the original LabQuest. It works with
LabQuest 2 or LabQuest 3.
Charging the Sensor
Connect Go Direct Surface Temperature to the included Micro USB Cable and
any USB device for two hours.
You can also charge up to eight Go Direct Surface Temperature Sensors using
our Go Direct Charge Station, sold separately (order code: GDX-CRG). An LED
on each Go Direct Surface Temperature indicates charging status.
Charging Blue LED on steady while sensor is connected to
the Charging Cable or Charging Station.
Fully charged Blue LED is off when charging is complete.
Providing Power
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-st
Go Direct®Surface
Temperature
(Order Code GDX-ST)
Go Direct Surface Temperature is designed for
use in situations in which low thermal mass or flexibility is required. Special
features include an exposed thermistor that results in an extremely rapid
response time.
Typical uses for Go Direct Surface Temperature include the following:
lSkin temperature measurements
lHuman respiration studies
lSpecific heat experiments
lHeat transfer experiments
lFriction and energy studies
Note: Vernier products are designed for educational use. Our products are not
designed nor are they recommended for any industrial, medical, or commercial
process such as life support, patient diagnosis, control of a manufacturing
process, or industrial testing of any kind.
What's Included
lGo Direct Surface Temperature
lMicro USBCable
Compatible Software
See www.vernier.com/manuals/gdx-st for a list of software compatible with
GoDirectSurfaceTemperature.
Getting Started
Please see the following link for platform-specific connection information:
www.vernier.com/start/gdx-st
Bluetooth Connection USB Connection
1. Install Vernier Graphical
Analysis™ on your computer,
Chromebook™, or mobile device. If
using LabQuest®, make sure
LabQuest App is up to date. See
www.vernier.com/ga4 for Graphical
Analysis availability or
www.vernier.com/downloads to
update LabQuest App.
2. Charge your sensor for at least
2hours before first use.
3. Turn on your sensor by pressing the
1. Install Graphical Analysis on your
computer or Chromebook. If using
LabQuest, make sure LabQuest
App is up to date. See
www.vernier.com/ga4 for software
availability or
www.vernier.com/downloads to
update LabQuest App.
2. Connect the sensor to the USB
port.
3. Launch Graphical Analysis or turn
on LabQuest. You are now ready to

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Specifications
Temperature range –25°C to 125°C (–13°F to
275°F)
Maximum temperature that the sensor can
tolerate without damage
150°C
Temperature sensor 20 kΩ NTC Thermistor
Accuracy ±0.5°C or better
Response time from 25°C to 100°C in water 5 seconds
Probe dimensions: probe length (handle plus
body)
Handle: 7 cm high, 3.5 cm
wide, 2 cm deep
Cable: 1 m
Submergible section: 7 cm
Care and Maintenance
Battery Information
Go Direct Surface Temperature contains a small lithium-ion battery in the
handle. 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 Surface Temperature 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
The body of the Go Direct Surface Temperature Sensor 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.
Connecting via Bluetooth
Ready to connect Red LED flashes when sensor is awake and
ready to connect via Bluetooth.
Connected Green LED flashes when sensor is connected via
Bluetooth.
Connecting via USB
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, fully charged Green LED solid when sensor is connected to
Graphical Analysis via USB and the unit is fully
charged.
Charging via USB,
connected via Bluetooth
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
Connect the sensor following the steps in the Getting Started section of this user
manual.
Important: Go Direct Surface Temperature is for use in air and water only. For
temperature measurements in harsher environments that require a more durable
probe, we recommend our Go Direct Temperature (order code GDX-TMP).
Calibration
It should not be necessary to perform a calibration when using this sensor. It is
calibrated before it ships.

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environment. The recycling of materials will help to conserve natural resources.
For more detailed information about recycling this product, contact your local
city office or your disposal service.
Battery recycling information is available at www.call2recycle.org
Do not puncture or expose the battery to excessive heat or flame.
The symbol, shown here, indicates that this product must not be disposed of
in a standard waste container.
Federal Communication Commission Interference Statement
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC rules.
These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment
generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause
harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If
this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and
on, the user is encouraged to try to correct the interference by one or more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.
FCC Caution
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference and
(2) this device must accept any interference received, including interference that may cause undesired operation
RF Exposure Warning
The equipment complies with RF exposure limits set forth for an uncontrolled environment. The antenna(s) used for this transmitter must
not be co-located or operating in conjunction with any other antenna or transmitter. You are cautioned that changes or modifications not
expressly approved by the party responsible for compliance could void your authority to operate the equipment.
IC Statement
This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject to the following two conditions:
(1) this device may not cause interference, and
(2) this device must accept any interference, including interference that may cause undesired operation of the device.
Industry Canada - Class B This digital apparatus does not exceed the Class B limits for radio noise emissions from digital apparatus
as set out in the interference-causing equipment standard entitled “Digital Apparatus,” ICES-003 of Industry Canada. Operation is subject
to the following two conditions: (1) this device may not cause interference, and
(2) this device must accept any interference, including interference that may cause undesired operation of the device.
To reduce potential radio interference to other users, the antenna type and its gain should be so chosen that the equivalent isotropically
radiated power (e.i.r.p.) is not more than that permitted for successful communication.
RF exposure warning: The equipment complies with RF exposure limits set forth for an uncontrolled environment. The antenna(s) used
for this transmitter must not be co-located or operating in conjunction with any other antenna or transmitter.
Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de licence. L’exploitation est
autorisée aux deux conditions suivantes :
(1) l’appareil ne doit pas produire de brouillage, et
(2) l’appareil doit accepter tout interférence radioélectrique, même si cela résulte à un brouillage susceptible d’en compromettre le
fonctionnement.
Cet appareil numérique respecte les limites de bruits radioélectriques applicables aux appareils numériques de Classe B prescrites dans
la norme sur le matériel interférant-brouilleur: “Appareils Numériques,” NMB-003 édictée par industrie Canada. L’utilisation est soumise
aux deux conditions suivantes:
(1) cet appareil ne peut causer d’interférences, et
(2) cet appareil doit accepter toutes interférences, y comprises celles susceptibles de provoquer un disfonctionnement du dispositif.
Afin de réduire les interférences radio potentielles pour les autres utilisateurs, le type d’antenne et son gain doivent être choisie de telle
façon que l’équivalent de puissance isotrope émis (e.i.r.p) n’est pas plus grand que celui permis pour une communication établie.
Avertissement d’exposition RF: L’équipement est conforme aux limites d’exposition aux RF établies pour un environnement non
supervisé. L’antenne (s) utilisée pour ce transmetteur ne doit pas être jumelés ou fonctionner en conjonction avec toute autre antenne ou
transmetteur.
How the Sensor Works
This probe uses the 20 kΩ NTC Thermistor, which is a variable resistor. When
the temperature increases, the resistance decreases non-linearly. The best-fit
approximation to this nonlinear characteristic is the Steinhart-Hart equation. At
25°C, the resistance is approximately 4.3% per °C. The interface measures the
resistance value, R, at a particular temperature and converts the resistance using
the Steinhart-Hart equation:
T = [K0+ K1(ln 1000R) + K2(ln 1000R)3]-1 – 273.15
where Tis temperature (°C), Ris the measured resistance in
kΩ,Ko=1.02119×10-3,K1= 2.22468 × 10-4, and K2= 1.33342 × 10-7. Our
programs perform this conversion and provide readings in °C (or other units, if
you load a different calibration).
Troubleshooting
First check that the sensor is responding: Connect the sensor and start the
data-collection program. Hold the tip of the sensor in your hand to warm it and
check that the temperature changes.
For additional troubleshooting and FAQs, see www.vernier.com/til/4052
Repair Information
If you have followed the troubleshooting steps and are still having trouble with
your Go Direct Surface Temperature, contact Vernier Technical Support at
[e-mail] 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.
Accessories/Replacements
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
Warranty
Warranty information for this product can be found on the Support tab at
www.vernier.com/gdx-st
General warranty information can be found at www.vernier.com/warranty
Disposal
When disposing of this electronic product, do not treat it as household waste. Its
disposal is subject to regulations that vary by country and region. This item
should be given to an applicable collection point for the recycling of electrical
and electronic equipment. By ensuring that this product is disposed of correctly,
you help prevent potential negative consequences on human health or on the

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Note: This product is a sensitive measurement device. For best results, use the cables that were provided. Keep the device away from
electromagnetic noise sources, such as microwaves, monitors, electric motors, and appliances.
Vernier Software & Technology
13979 SW Millikan Way • Beaverton, OR 97005-2886
Toll Free [phone] • [phone] • Fax [phone]
[e-mail] • www.vernier.com
Rev. 2/19/2021
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