Little Bird
4 channel 5V relay module with light coupling 5V
A 4-channel relay module with opto-isolated inputs for safe, reliable switching of high-power loads. Each relay is rated for up to 10A at 250VAC or 30VDC, ma...
A 4-channel relay module with opto-isolated inputs for safe, reliable switching of high-power loads. Each relay is rated for up to 10A at 250VAC or 30VDC, making it suitable for controlling lights, motors, heaters, and other mains-powered devices from a microcontroller.
The opto-isolators protect your microcontroller from electrical noise and voltage spikes, while requiring only 2mA per channel to trigger. Although designed for 5V logic, the module also works reliably with 3.3V systems.
Key Features
- 4 Independent Channels – Control four separate loads with individual relay outputs
- Opto-Isolated Inputs – Protects your microcontroller from high-voltage interference and ground loops
- Low Input Current – Only 2mA per channel, safe for direct microcontroller connection
- 3.3V/5V Compatible – Works with both 3.3V and 5V logic levels
- High-Power Switching – Each relay rated for 10A @ 250VAC / 10A @ 30VDC
- NO and NC Contacts – Each relay provides both normally-open and normally-closed terminals
- Status LEDs – Individual LED indicators show when each relay is energised
- Test Jumper – Disconnect VCC to test logic without activating relays
Ideal For
- Home automation and smart lighting control
- Arduino, Raspberry Pi, and ESP32 projects
- Controlling motors, pumps, and solenoids
- Switching mains-powered appliances
- Industrial and PLC control applications
Specifications
- Channels – 4
- Supply Voltage – 5V DC (also works at 3.3V)
- Input Logic – Active LOW (relay activates when input is pulled low)
- Input Current – 2mA per channel (opto-isolator/LED)
- Relay Coil Current – 60mA per relay
- Contact Rating – 10A @ 250VAC / 10A @ 30VDC
- Contact Type – SPDT (NO + NC + COM per channel)
- Dimensions – 73 × 54 × 19mm
Pinout
- VCC – 5V power supply
- GND – Ground
- IN1–IN4 – Control inputs (active LOW)
- COM – Common contact (one per relay)
- NO – Normally Open contact
- NC – Normally Closed contact
Jargon buster
Plain-language definitions for the technical terms used above.
- 3.3V and 5V logic levels
- Logic level refers to the voltage a board uses to represent digital on and off signals. Support for both 3.3V and 5V logic means this breakout can connect more easily to common microcontrollers and single-board computers without extra level-shifting hardware.
- active LOW
- Active LOW means an input is considered switched on when it is connected to a low voltage or ground. This matters when wiring buttons, switches, or other trigger signals so the board responds in the expected way.
- ESP32
- ESP32 is a family of microcontroller modules with built-in wireless features such as Bluetooth and WiFi. Knowing this product uses an ESP32-based module helps explain how it provides wireless serial communication and firmware update features.
- LED
- A light-emitting diode is a small electronic component that lights up when current flows through it in the correct direction. In this kit, LEDs create the flashing effect, so polarity and correct soldering matter for the project to work.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
Find this product in
Robotics & Motion
Related Tutorials
Free guides on learn.littlebird.com.au
