AC220V ESP8266 1 Channel WIFI Relay Module ESP-12S Wifi Development Board

The AC220V ESP8266 1 Channel WIFI Relay Module is an IoT-enabled relay control board that integrates the powerful ESP-12S WiFi module with a high-capacity AC relay, enabling remote switching of AC220V loads over WiFi networks. Electronics engineers, automation technicians, and IoT developers use this module to build smart home systems, industrial automation projects, and remote device control applications. This product solves the critical challenge of controlling high-voltage AC equipment remotely without requiring expensive industrial PLC systems or dedicated control infrastructure.

Product Overview

The ESP8266 1 Channel WIFI Relay Module combines the ESP-12S WiFi microcontroller with a single-channel relay rated for AC220V operation, allowing seamless integration of WiFi connectivity with high-voltage switching capability. The ESP-12S processor operates at 80MHz with 160MHz turbo mode, featuring 4MB flash memory and robust WiFi 802.11 b/g/n support. The relay circuit includes optical isolation between the control logic and AC switching circuits, preventing voltage spikes and noise from affecting the microcontroller while maintaining safe galvanic isolation. The module supports multiple control protocols including HTTP REST APIs, MQTT messaging, and custom firmware development through the Arduino IDE, making it adaptable to virtually any IoT ecosystem.

This development board excels in applications requiring reliable AC load switching with remote WiFi control capabilities. The onboard voltage regulation provides stable 3.3V to the ESP-12S module, while the relay driver circuit ensures proper gate-drive voltage for the switching element. The module includes status indicator LEDs for relay state and power status, facilitating real-time debugging during development. Built-in protection features include reverse polarity protection on the AC input, transient suppression on the relay coil, and current limiting resistors on all GPIO lines, making this module suitable for both prototype development and field deployment in demanding environments.

Key Specifications

Specification	Details
Product Type	WiFi Relay Module with ESP8266
Brand	Generic OEM
Origin	Original/Authentic
Warranty	7 days on manufacturing defects
Shipping	1-5 days from Bengaluru
Delivery	7-8 days across India
Support	24/7 via Email and WhatsApp
WiFi Module	ESP-12S with 4MB Flash Memory
Processor	ESP8266 80MHz/160MHz Turbo
Relay Specification	1 Channel AC220V 10A Rating
Input Voltage	AC 220V 50Hz/60Hz
Control Voltage	3.3V DC Logic Level
Isolation	Optical Isolation between Control and AC Circuits

Key Features

• ESP-12S WiFi Module with 4MB Flash enabling full Arduino IDE compatibility and custom firmware development for advanced IoT applications
• AC220V 10A Relay with optical isolation providing safe galvanic separation between low-voltage control circuitry and high-voltage switching elements
• Multiple Control Protocols supporting HTTP REST APIs, MQTT, and CoAP for seamless integration with popular IoT platforms and cloud services
• Onboard Status LEDs for Power and Relay State indication enabling real-time visual feedback during development and troubleshooting
• Built-in Protection Circuits including reverse polarity protection, transient suppression, and current limiting resistors for enhanced reliability
• Compact Form Factor with standard pin headers allowing easy integration into breadboards and custom PCB designs

Applications and Use Cases

• Smart Home Automation Systems for remote control of lighting, fans, water heaters, and air conditioning units through WiFi-enabled mobile applications
• Industrial IoT Monitoring where equipment status and control signals are transmitted over WiFi networks for centralized factory floor management
• Agricultural Automation Projects for remote switching of irrigation pumps, greenhouse ventilation systems, and livestock watering equipment
• Laboratory and Test Equipment Control enabling researchers to automate power sequencing for multi-stage experimental setups via networked interfaces
• Building Energy Management Systems for demand-side management and load scheduling of HVAC and lighting systems in commercial facilities
• Remote Device Control in off-grid installations where WiFi mesh networks provide connectivity for distributed relay switching across multiple locations

How to Use

Begin by connecting the AC220V power source to the relay input terminals, ensuring proper polarity and secure terminal connections to prevent arcing. The module requires a 3.3V DC power supply for the ESP-12S microcontroller, which can be derived from an isolated AC-DC converter or a dedicated 3.3V regulator module. Program the ESP-12S using the Arduino IDE by installing the ESP8266 board package, then upload your custom firmware or use pre-built sketches to configure WiFi credentials, relay control logic, and communication protocols. Connect the relay output terminals to your AC220V load device, ensuring the total current draw does not exceed the 10A relay rating. Test the relay operation using GPIO pin D1 (or your configured control pin) by sending HTTP requests or MQTT messages from your control application to verify bidirectional communication and relay switching.

For production deployments, implement proper circuit protection by adding a thermal fuse or circuit breaker on the AC input side rated for 10A, and use shielded twisted-pair cabling for relay control signals to minimize EMI coupling. Configure the module to connect to your home WiFi network or industrial IoT platform, then verify relay state synchronization across all control interfaces. Implement authentication mechanisms such as API tokens or MQTT username/password credentials to prevent unauthorized device control. Monitor the module temperature during continuous operation, as the relay coil generates heat during extended switching cycles; ensure adequate ventilation around the module to maintain safe operating temperatures below 70 degrees Celsius.

Frequently Asked Questions

Can I control multiple relays with a single ESP-12S module?

The standard AC220V ESP8266 1 Channel module includes one relay, but the ESP-12S processor has multiple GPIO pins available. You can design custom firmware and add external relay driver circuits to control additional relays using the same microcontroller. However, each relay will require its own driver circuit, isolation transformer, and AC switching components. Alternatively, you can purchase multiple single-channel modules and synchronize them via WiFi for multi-channel switching applications.

What is the maximum switching frequency for the relay?

The relay contact rating is typically 10A at 220V AC for resistive loads. Mechanical relays have a switching frequency limitation of approximately 10-50 times per minute for extended lifespan due to mechanical wear on the contacts. For applications requiring high-frequency switching (above 100Hz), you should use solid-state relays or thyristor-based switching circuits instead. Exceeding the recommended switching frequency will significantly reduce relay contact life and increase failure risk.

Does this module work with 110V AC or only 220V AC?

The module is specifically rated for AC220V operation. Using it with 110V AC is not recommended as the relay coil may not receive sufficient voltage to pull in reliably, causing intermittent switching failures. However, the relay contacts themselves can typically handle lower voltages, so the main concern is the coil activation voltage. For 110V AC applications, you should use a module specifically designed for that voltage or use a step-up transformer to convert 110V to 220V.

How do I program the ESP-12S module with custom firmware?

Install the Arduino IDE on your computer and add the ESP8266 board package through the Boards Manager. Connect the module to your computer via a USB-to-UART adapter on the TX/RX pins, then select the ESP8266 board and appropriate COM port. Write your sketch using Arduino C++ syntax to control the relay GPIO pin, configure WiFi connectivity, and implement your desired control logic. Upload the compiled firmware to the module's 4MB flash memory. Detailed tutorials and example sketches are available in the official ESP8266 Arduino documentation.

When will I receive my order?

Orders are dispatched within 1-5 business days from our Bengaluru warehouse. Delivery takes 7-8 days to most locations across India.

What is your return and warranty policy?

We offer a 7-day return policy on manufacturing defects only. Contact support within 7 days of receipt for free replacement or full refund. Not applicable for user damage or misuse.

Are bulk discounts available?

Yes, wholesale pricing for orders of 10 or more units. Contact our sales team via WhatsApp or email for a customized bulk quote.

Why Buy from The Engineer Store

• Genuine Products: Sourced directly from authorized distributors with authentication
• Expert Team: Our technical team validates every product before listing
• Fast Shipping: Dispatched within 1-5 days from our Bengaluru warehouse
• Pan-India Delivery: 7-8 days to Mumbai, Delhi, Chennai, Hyderabad, Pune, Kolkata
• Payment Options: COD, UPI, credit/debit cards, net banking, EMI available
• Technical Support: 24/7 expert guidance via email and WhatsApp
• Returns: 7-day return policy on manufacturing defects only

Buy AC220V ESP8266 1 Channel WIFI Relay Module ESP-12S Wifi Development Board Online in India

Purchase the AC220V ESP8266 1 Channel WIFI Relay Module ESP-12S Wifi Development Board online at The Engineer Store, India's trusted source for genuine electronics. We deliver across Bengaluru, Mumbai, Delhi, Chennai, Hyderabad, Pune, Kolkata, Ahmedabad, Jaipur, and Surat. Get the best price on AC220V ESP8266 1 Channel WIFI Relay Module ESP-12S Wifi Development Board with fast shipping and expert support.

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