Dragino S31B-LB LoRaWAN Temperature & Humidity Sensor

1. Introduction

The Dragino S31B-LB is a sophisticated LoRaWAN Temperature and Humidity Sensor designed for Internet of Things (IoT) solutions. This device accurately measures ambient temperature and relative air humidity, transmitting this data to an IoT server using the LoRaWAN wireless protocol. Its robust design and advanced features make it suitable for various environmental monitoring applications.

Figure 1: Front view of the S31B-LB sensor, showing the main unit and external antenna. This image illustrates the compact and durable design of the device.

2. Key Features

• LoRaWAN 1.0.3 Class A: Supports standard LoRaWAN protocol for wide compatibility.
• Ultra-low Power Consumption: Designed for extended battery life, up to 5 years with an 8500mAh Li-SOCI2 battery.
• External SHT31 Probe: Features a 3-meter external SHT31 sensor for precise temperature and humidity measurements.
• Wide Measurement Range: Capable of measuring temperatures from -55°C to 125°C.
• Temperature & Humidity Alarm: Allows users to set alarms for instant notifications on threshold breaches.
• Datalog Feature: Stores data when the LoRaWAN network is unavailable and uploads it once connectivity is restored.
• BLE Configuration: Enables easy configuration via Bluetooth Low Energy.
• Wireless OTA Update: Supports Over-The-Air firmware updates for convenient maintenance.
• Pre-loaded Unique Keys: Each unit comes with unique keys for seamless LoRaWAN network registration.

3. Package Contents

The S31B-LB package typically includes the following items:

• 1 x Dragino S31B-LB LoRaWAN Temperature & Humidity Sensor Unit
• 1 x External SHT31 Temperature & Humidity Probe (3 meters)

4. Setup Guide

Follow these steps to set up your S31B-LB sensor:

1. Unpack the Device: Carefully remove the S31B-LB sensor and its external probe from the packaging.
2. Connect the Probe: Insert the external SHT31 probe connector into the designated port on the S31B-LB unit. Ensure it is securely fastened.


Figure 2: Angled view of the S31B-LB sensor, highlighting the connection point for the external SHT31 probe. The probe is designed to be waterproof and anti-condensation for long-term outdoor use.

3. LoRaWAN Registration: Each S31B-LB unit is pre-loaded with unique keys (DevEUI, AppEUI, AppKey). Register these keys with your local LoRaWAN Network Server (LNS). Refer to your LNS documentation for specific registration procedures.
4. Power On: The device is powered by an internal 8500mAh Li-SOCI2 battery. Once the probe is connected and keys are registered, the device will automatically attempt to connect to the LoRaWAN network upon power-on.
5. BLE Configuration (Optional): For initial configuration or parameter adjustments, you can use a compatible mobile application to connect to the S31B-LB via Bluetooth Low Energy (BLE). This allows for easy setup without needing a direct physical connection.
6. Placement: Position the sensor and its external probe in the desired location for temperature and humidity monitoring. Ensure the probe is exposed to the environment you wish to measure, avoiding direct sunlight or heat sources that could skew readings.

5. Operating Instructions

Once set up and connected to the LoRaWAN network, the S31B-LB operates autonomously:

• Data Measurement: The SHT31 probe continuously measures temperature and relative humidity.
• Data Transmission: Measured data is periodically transmitted to your LoRaWAN network server. The transmission interval can typically be configured via BLE or the LoRaWAN network server.
• Temperature & Humidity Alarm: You can configure specific temperature and humidity thresholds. If the measured values exceed or fall below these thresholds, the sensor can trigger an alarm, sending an immediate notification to your IoT platform.
• Datalog Function: In instances where the LoRaWAN network connection is temporarily lost, the S31B-LB will store measurement data internally. Once the network connection is re-established, the stored data will be uploaded to ensure no data loss.

6. Maintenance

The S31B-LB is designed for low maintenance:

• Battery Life: The internal 8500mAh Li-SOCI2 battery provides an estimated operational life of up to 5 years under typical usage conditions. Battery replacement should be performed by qualified personnel if necessary.
• Firmware Updates: The device supports wireless Over-The-Air (OTA) firmware updates. Check the Dragino official website or your LoRaWAN network provider for available updates to ensure optimal performance and access to new features.
• Probe Cleaning: While the SHT31 probe is housed in a waterproof, anti-condensation casing, occasional gentle cleaning of the probe's exterior may be necessary to remove dust or debris that could accumulate over time. Use a soft, damp cloth and avoid abrasive materials.

7. Troubleshooting

If you encounter issues with your S31B-LB sensor, consider the following:

• No Data Transmission:
  • Verify that the device's unique keys (DevEUI, AppEUI, AppKey) are correctly registered on your LoRaWAN Network Server.
  • Ensure the sensor is within range of a LoRaWAN gateway. Obstructions or distance can affect signal strength.
  • Check the battery status. Although designed for long life, extreme conditions or prolonged high-frequency transmissions can reduce battery life.
• Inaccurate Readings:
  • Ensure the external probe is securely connected to the main unit.
  • Verify the probe's placement. Avoid direct sunlight, heat sources, or areas with poor air circulation that could affect readings.
  • Clean the probe gently to remove any accumulated dust or debris.
• BLE Connection Issues:
  • Ensure Bluetooth is enabled on your mobile device.
  • Make sure you are using the correct mobile application for Dragino devices.
  • Ensure the sensor is powered on and within close proximity to your mobile device.

For further assistance, refer to the official Dragino documentation or contact their technical support.

8. Specifications

9. Warranty and Support

For information regarding product warranty, please refer to the warranty policy provided at the time of purchase or visit the official Dragino website. For technical support, troubleshooting assistance, or further inquiries, please contact your vendor or Dragino's customer support channels. Ensure you have your product model number (S31B-LB) and purchase details ready when seeking support.