A 5V Relay Module Remote WiFi Switch is a smart control system that lets you switch electrical devices ON/OFF remotely using WiFi (usually via a phone app or web interface).
It combines two main parts:
- Relay module (5V control side)
- WiFi controller (usually ESP8266 or ESP32 based)
What it does
It allows you to control high-voltage or high-current devices like:
- Lights
- Small appliances
- Heaters (within relay rating)
- Fans
- Power sockets (DIY smart plug setups)
All controlled from your phone or network.
How it works
- Your phone sends a command over WiFi
- The WiFi module (ESP8266/ESP32) receives it
- It triggers the 5V relay coil
- The relay physically switches the high-voltage circuit ON/OFF
So the low-voltage WiFi side is safely isolated from the mains side (when built correctly).
Typical specifications
- Input voltage: 5V DC
- Relay channels: 1 / 2 / 4 / 8 channel versions
- Relay rating: usually 10A @ 250V AC (check actual marking)
- Control chip: ESP8266 / ESP32 (most common)
- Control method: WiFi (2.4GHz)
- App support: commonly Tuya / Smart Life or custom firmware
App control
Many modules use cloud apps like:
- Tuya Smart
- Smart Life (very similar ecosystem)
Features usually include:
- Remote ON/OFF
- Timer scheduling
- Countdown function
- Voice control (Alexa / Google Home integration)
Wiring basics
Low-voltage side:
- 5V power → module VCC
- GND → ground
- WiFi handles control logic
High-voltage side:
- Live wire goes through relay COM → NO terminal
- Load connects to output side
Only switch the LIVE wire, not neutral.
Important safety notes
- Mains voltage (220–240V in South Africa) is dangerous
- Enclosure is required (no exposed terminals)
- Do not exceed relay rating (10A is often optimistic)
- Not suitable for high inrush loads (large motors, compressors) unless properly rated
When to use it
Good for:
- Smart home DIY projects
- Remote switching of lights or small appliances
- Automation systems
- IoT learning projects
When NOT to use it
Avoid for:
- High-power geysers or ovens (unless properly rated relay/contactor used)
- Industrial motors
- Safety-critical systems
This product was added to our catalog on Saturday 06 June, 2026.