LoRa Relay Switch – Control Home Appliances using LoRa

Overview: Control Home Appliances using LoRa Relay Switch

In this project, we will make a LoRa Relay Switch or LoRa Based Power Relay Control System using Arduino & RFM98 LoRa Module. The LoRa Relay Node will able able to transmit the data to Gateway. We can press the switch button on Sender or LoRa Node side which can turn OFF/ON the relay remotely.

The LoRa Relay Power Switch is a smart LoRa device for remotely controlling industrial and home appliances remotely. The Remote Power Switch can be used to remotely control the power of external devices or appliances. Appliances include the control of general devices, lighting, irrigation systems, pumps, remote servers, towers, enabling and disabling security systems, access control of gates and doors.

Communication with the Remote Power Switch is done using the integrated loRaWAN module. All you need to do is upload the code using Micro-USB port, connect to your LoRaWAN network, connect the Remote Power Switch to your power outlet, and connect your appliances to the Remote Power Switch.

Before getting started with this project, you can check our previous LoRa Based Projects, which will clear your all concepts of LoRaWAN Technology.

Bill of Materials

Following are the components required for making this project. All the components can be easily purchased from Amazon. The component purchase link is given below.

LoRa Relay Module 30A

This 30A Lora Relay Node or Switch is a relay module that could be controlled by Lora, with max current 30A/240V. Based on LoRa Module RFM98W, it supports max 4~5 km Lora communication.

This Lora relay module is preloaded Arduino Pro Mini(3.3v 8M) bootloader and simple demo firmware Lora Relay V1.1, the users could freely change/update the firmware with Arduino IDE, with a common UART tool.

Features

• Controller: Atmega328P
• Arduino bootloader: Pro mini(3.3V/8M)
• Lora frequency: 433M/ 868M/ 915M
• Current: 30A@240VAC
• Input Voltage: 12V

LoRa Receiver: Lora Radio (433M/868M/915M)

The Lora Radio Receiver is a mainboard based on the ATmega328 and 433MHZ/868MHz/915MHz RFM95 LoRa module. The LoRa Radio allows the user to send data and reach extremely long ranges at low data-rates. It provides ultra-long range spread spectrum communication and high interference immunity whilst minimizing current consumption. It has Arduino pro mini 3.3V 8MHz bootloader on this board and uses the CP2104 as USB to serial to upload the code using Arduino IDE. In this Lora Relay Control project, we will use it as a Receiver Gateway.

Features

• BAT Input Voltage: 3.4-4.2V
• Integrated Power Control System
• 127 dB Dynamic Range RSSI
• Uses the License-free ISM band: “European ISM” @ 433MHz/868MHz/915MHz
• +5 to +20 dBm up to 100 mW Power Output Capability (power output selectable in software)
• ~100mA Peak during +20dBm transmit, ~30mA during active radio listening
• Range of approx. 2Km, depending on obstructions, frequency, antenna, and power output

Setting Up LoRa Relay Receiver

The Lora Power Relay can be used to switch the AC bulb light on or off. I integrated the 30A current relay, which will give you a wide use for the large current devices.

For the demonstration process I use a bulb and connected to the output of the Relay. The device can be powered up either using a 12V Adapter or a 12V Battery. Here is a circuit diagram of the entire connection.

In order to upload code to the microcontroller, we need a USB-to-TTL or a FTDI Module.

Make a connection between Lora Relay Module and FTDI as shown in the table below.

So the complete connection and setup can be done as shown in the image below.

Setting Up LoRa Sender/Controller

Now let us setup the receiver now. The Receiver module has two extra connections. We need to connect a 0.96″ I2C OLED Display and a Push Button Switch.

The Assembly of the circuit can be either done in a breadboard or it can be done using a Custom design PCB.

LoRa Relay Receiver Code

The Receiver Controller Code that need to uploaded to LoRa Relay Node is given below.

The code requires a LoRa Library to compile. So download the LoRa Library and add it to the Arduino IDE.

In order to upload the code, from the top Arduino IDE menu, select Tools-> Board-> Arduino Pro or Pro Mini. Then select the correct COM Port and click the upload button.

If you upload the firmware fails, press and hold the Reset button before uploading the firmware. When the IDE shows below, then release the button that may help to upload the firmware success. That’s we need a reset the MCU when uploading the firmware.

LoRa Sender/Controller Code

The LoRa Sender code for Controlling LoRa Relay Wirelessly is given below. Before uploading code you need to install the OLED Library first along with the LoRa Library.

1. LoRa Library: Download
2. Adafruit GFX Library: Download
3. SSD1306 Library: Download

For uploading code select the select Tools-> Board-> Arduino Pro or Pro Mini. Then select the correct COM Port and click the upload button.

Control Home Appliances using LoRa Relay Switch

After setting up and uploading the code in both the LoRa Node & Gateway, you can now check the working of the device. Power ON both the circuit and then strat testing.

When you press the push button on the Sender side the Relay gets activated and Bulb turns ON.

When you press the push button once again on the Sender side the Relay gets disconnected and Bulb turns OFF.

Video Tutorial & Guide