8 Channel Relay Board - 5V Opto-Isolated for Arduino & Raspberry Pi

Specifications

• Channels: 8 Independent Relays.

• Control Signal: 5V DC (Active Low).

• Switching Capacity: 10A @ 250VAC / 10A @ 30VDC.

• Isolation: Opto-isolated.

• Indication: Individual LED status indicators for each channel.

• Power Requirement: 5V DC for VCC.

• Dimensions: 138mm x 56mm x 19mm.

• Terminals: High-quality Screw Terminals (NO, COM, NC).

Key Applications & Projects

• Smart Home Automation: Control 8 different lights or appliances via Wi-Fi (using an ESP32).

• Industrial PLC Replacement: Creating custom logic controllers for machinery.

• Automated Greenhouses: Managing water pumps, fans, and grow lights on a schedule.

• Audio/Visual Switching: Routing high-power signals in theatre or stage setups.

Project Evolution

• Past Projects (Prerequisites): If you've controlled a single LED or a single relay module, you've mastered the basics.

• Feature Upgrade: This board unlocks Multi-Load Synchronised Control. You can now program complex "scenes" (e.g., turn off the lights, lock the door, and start the fan with one command).

• Effort/Requirements: Beginner-Friendly. Requires only basic digital output programming and standard jumper wires.

Virtual Technician & Wiring

⚠️ Safety Warning: You are dealing with Mains Voltage (220V). Always disconnect the power before wiring and ensure all connections are tight and insulated.

Package Includes: 1 x 8 Channel Relay Board - 5V Opto-Isolated

Frequently Asked Questions (FAQ)

• Can I use this with a 3.3V ESP32 or Raspberry Pi? Yes, though it is a 5V board, most 3.3V logic pins can trigger the opto-isolators; however, a level shifter is recommended for long-term reliability.
• What does "Active Low" mean? It means the relay turns ON when you send a LOW (0V) signal and OFF when you send a HIGH (5V) signal.
• Can I control AC motors with this? Yes, up to a 10A load.
• Does it need an external power supply? Yes, for 8 relays, we recommend a 5V 1A power supply as the Arduino's 5V pin may not provide enough current.
• How do I separate the logic power from the relay power? Remove the VCC-JDVCC jumper and provide separate 5V to the JDVCC pin.
• What is the LED for? It lights up when the specific relay channel is energized.
• Are the screw terminals removable? No, they are securely soldered to the PCB.
• Can I use this for DC loads? Yes, it switches DC up to 30V.
• How many relays can I turn on at once? All 8 can be active simultaneously if your power supply can handle the ~500mA draw.
• Is it compatible with 24V? The control is 5V, but you can switch a 24V load.
• Does it have mounting holes? Yes, there are four mounting holes in the corners.
• Is it "Clicky"? Yes, mechanical relays make a distinct clicking sound when they switch.
• What is the life expectancy? Rated for over 100,000 mechanical operations.
• Does it work with the "Blynk" or "Home Assistant" app? Yes, it is the standard hardware used for such IoT projects.
• What wire gauge should I use? Up to 14 AWG for the screw terminals.
• Is it protected against reverse polarity? No, ensure VCC and GND are connected correctly.
• Can it switch high-frequency signals? No, mechanical relays are meant for slow switching (lamps, pumps, etc.).
• Does it generate heat? Minimal heat is generated by the coils when energized.
• What is the "NC" terminal used for? It’s used for devices that should be ON by default and turn OFF when you send a signal.
• Is the chip/silicon verified? Yes, we use high-grade PC817 opto-isolators for maximum protection.