5 V Four-Channel Relay Module with Optocouplers

Add separately controlled relay outputs to a compatible microcontroller build with a compact four-channel board.

Bring four switching channels into one project

• ✅ Use inputs IN1 to IN4 to control separate output channels.
• ✅ Connect field wiring through the screw terminals rather than loose temporary contacts.
• ✅ Plan the relay supply arrangement around the VCC, GND and JD-VCC connections.

5 V DC four-channel relay module with optocouplers and low-level trigger inputs; approximately 75 × 50 mm. Match the wiring and connected loads to the actual relay markings and control-circuit requirements.

Photos show the actual board and wiring examples; controller, power supply and example loads are not included.

Match the relay board to your circuit and build your next switching project.