© Copyright Sensirion AG, Switzerland
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2
Standard Operation
2.1
Assembly Instructions
Take the two supports and break them apart. Slide the circuit board into the slots in the supports, with one
support on each side of the LC display. Remove battery insulation foil. Optionally, the temperature can be
displayed in °F by pressing the switch button while inserting the battery.
2.2
Operation in Standalone Mode
This is the default operating mode. The measured values are shown on the LC display. The upper line optionally
shows relative humidity or dew point temperature while the lower line shows temperature. To switch between
relative humidity and dew point display, briefly press the switch button.
For displaying temperature values in °F, press the switch button while inserting the battery.
2.3
Operation in Bluetooth Mode
To enable (and disable) Bluetooth Smart mode, press the switch button for more than 1 second. When enabled,
the Bluetooth symbol in the display starts blinking. The device ID is shown on the display for a short time and the
SHT31 Smart Gadget is visible for master devices (“advertising mode”). In this time period, a master device
running a compatible app or software can establish a connection to the SHT31 Smart Gadget. An effective
connection to a master device is indicated by a constantly displayed Bluetooth symbol. If the connection to a
master device is lost, the Bluetooth symbol will start blinking. Once the SmartGadget is within reach again the
connection is established automatically. The battery life is improved when the Bluetooth mode is disabled.
2.4
Connecting to a Bluetooth Device
To connect the Smart Gadget to a smartphone, the Smart Gadget app has to be installed on the smartphone and
Bluetooth has to be enabled on the smartphone. To connect to a Smart Gadget, the corresponding Smart Gadget
has to be selected in the “Settings” tab in the app.
Smartphone apps can be downloaded from the corresponding app stores:
iOS (Apple iTunes Store):
https://itunes.apple.com/US/app/id787249829?mt=8
Android (Google Play Store):
https://play.google.com/store/apps/details?id=com.sensirion.smartgadget&hl=de
Please note that in order to work with the Smart Gadget, a smartphone or tablet needs to be Bluetooth 4.0
compatible.
2.5
Using the Smart Gadget as a Data Logger
The Smart Gadget stores the measurement values in the built-in memory. The measurement interval can be
defined through the app (“Settings”). The Smart Gadget will log measurement values even if the Bluetooth
connection is terminated. The stored values can be downloaded and displayed on the smartphone via the app.
2.6
System Requirements
In order for a mobile device to work with the Smart Gadget it needs to be Bluetooth 4.0 (also known as Bluetooth
Low Energy, BLE or Bluetooth Smart). This is the case for the majority of Android devices starting from
approximately generation 2013 and newer, Apple iPhones generation 4S and newer, and Apple iPad generation
3 and newer.