The Relay ESP01S is a compact and versatile relay module designed to work seamlessly with the ESP-01S Wi-Fi module. Manufactured by ESP, this component allows users to control high-voltage devices remotely via Wi-Fi. It is widely used in IoT applications, home automation systems, and smart appliances due to its ease of integration and reliable performance.
This circuit is a WiFi-enabled relay control system using an ESP8266-01 module and an MCP23017 I/O expander. The ESP8266 communicates with the MCP23017 via I2C to control an 8-channel relay module based on the state of 8 rocker switches, allowing for remote and manual control of connected devices.
Open Project in Cirkit Designer
This circuit consists of an ESP-01 microcontroller connected to an IR receiver. The ESP-01 is configured to receive data from the IR receiver through its GPIO0 pin, and both components share a common ground and power connection. The provided code for the ESP-01 microcontroller is a template with empty setup and loop functions, indicating that the specific functionality for the IR data processing has not been implemented yet.
Open Project in Cirkit Designer
This circuit features an ESP32 microcontroller connected to two 4-channel relay modules and a LORA_RA02 module. The ESP32 uses its GPIO pins to control the relay channels, enabling switching of connected devices, and to communicate with the LORA_RA02 module for wireless data transmission. The relays and the LORA module are powered by a 5v battery, with common ground shared across the components.
Open Project in Cirkit Designer
This circuit connects an NRF24L01 wireless transceiver module to an ESP8266 NodeMCU microcontroller. The ESP8266 controls the NRF24L01 via SPI communication, using its GPIO pins D1, D2, D5, D6, and D7 for CE, CSN, SCK, MISO, and MOSI respectively. The circuit is designed for wireless data communication, with the ESP8266 managing the network protocol and data handling, while the NRF24L01 handles the RF communication.
Open Project in Cirkit DesignerThe Relay ESP01S module has two main interfaces: the relay terminal block and the ESP-01S header pins.
| Pin Name | Description |
|---|---|
| VCC | 5V power input for the relay module |
| GND | Ground connection |
| TX | Transmit pin of the ESP-01S module |
| RX | Receive pin of the ESP-01S module |
| GPIO0 | Control pin for the relay (active LOW) |
| GPIO2 | General-purpose I/O pin (optional use) |
| Terminal | Description |
|---|---|
| COM | Common terminal for the relay |
| NO | Normally Open terminal (default open) |
| NC | Normally Closed terminal (default closed) |
The following code demonstrates how to control the Relay ESP01S using an ESP-01S module connected to an Arduino UNO.
#include <SoftwareSerial.h>
// Define RX and TX pins for ESP-01S communication
SoftwareSerial espSerial(2, 3); // RX = Pin 2, TX = Pin 3
// Define GPIO0 pin for relay control
const int relayPin = 4;
void setup() {
// Initialize serial communication with ESP-01S
espSerial.begin(9600);
// Initialize relay control pin
pinMode(relayPin, OUTPUT);
digitalWrite(relayPin, HIGH); // Ensure relay is off initially
// Debugging via Serial Monitor
Serial.begin(9600);
Serial.println("Relay ESP01S Control Initialized");
}
void loop() {
// Example: Turn relay ON for 5 seconds, then OFF for 5 seconds
Serial.println("Turning relay ON");
digitalWrite(relayPin, LOW); // Activate relay (active LOW)
delay(5000); // Wait for 5 seconds
Serial.println("Turning relay OFF");
digitalWrite(relayPin, HIGH); // Deactivate relay
delay(5000); // Wait for 5 seconds
}
Relay Not Activating:
ESP-01S Not Responding:
High-Voltage Device Not Working:
Can I use a 3.3V power supply for the relay module? No, the relay module requires a 5V power supply to operate correctly.
Is the Relay ESP01S compatible with other ESP modules? The module is specifically designed for the ESP-01S. Other ESP modules may not fit the header pins.
How do I reset the ESP-01S module? Pull the RESET pin of the ESP-01S module LOW momentarily to reset it.
By following this documentation, you can effectively integrate the Relay ESP01S into your projects and troubleshoot common issues.