5V 4-Channel Relay Module with Optocoupler
High-Power Switching Module for Microcontroller Control
This 4channel relay module enables a microcontroller to independently control up to four highpower devices such as lights, motors, and solenoids. Each relay provides complete electrical isolation between the lowvoltage control circuit and the highpower load circuit, protecting your microcontroller [citation:4][citation:11].
Controls 4 Independent AC/DC Loads - Each relay can switch up to 250V AC @ 10A or 30V DC @ 10A [citation:1][citation:8].
Optocoupler Isolation Provides excellent antiinterference capability and protects the control circuit [citation:2][citation:8].
Operating voltage is 5V DC with each channel requiring 15-20mA drive current [citation:2][citation:8].
Total module operating current is approximately 70mA per relay (300mA all four active) [citation:12].
Use an external 5V power supply for stable operation; Arduino 5V pin may not supply sufficient current.
Technical Specifications
| Parameter | Value |
|---|
| Operating Voltage | 5V DC [citation:4] |
| Trigger Voltage | 3.3V to 5V DC [citation:4] |
| Channels | 4 |
| Maximum Load (AC) | 250V @ 10A [citation:1][citation:8] |
| Maximum Load (DC) | 30V @ 10A [citation:1][citation:8] |
| Relay Type | SPDT (NO, NC, COM) [citation:2] |
| Isolation | Optocoupler [citation:4][citation:11] |
| Dimensions | ~75mm x 55mm x 19mm [citation:2][citation:8] |
= Pin Configuration =
*Input Pins (Control Side):*
- VCC: 5V DC power supply
- GND: Ground connection
- IN1 - IN4: Control pins for each relay (active LOW by default) [citation:8]
- JD-VCC: Relay power supply (jumper with VCC for same power source) [citation:2][citation:12]
Most modules are active LOW - a LOW signal (0V) activates the relay [citation:8].
Remove VCCJDVCC jumper for external relay power supply.
*Output Terminals (Load Side):*
- COM: Common terminal
- NO (Normally Open): Load connects here when relay is activated [citation:2]
- NC (Normally Closed): Load connects here when relay is deactivated [citation:2]
Applications
- Home automation (lights, fans, appliances)
- Industrial control systems
- Robotics and IoT projects
- Security systems (alarms, locks)
Versatile Control Manage multiple highpower devices simultaneously
Wide Compatibility - Works with Arduino, ESP32, Raspberry Pi
√ Each relay has independent indicator LED for status monitoring
√ Standard screw terminals for easy load wiring
√ Includes flyback diodes for protection against voltage spikes
Troubleshooting
Relays not activating:
- Ensure the module is powered with a stable 5V DC supply
- Check signal logic: module is active LOW by default [citation:8]
- Remove and reconnect VCCJDVCC jumper if using external power
Load not switching:
- Verify wiring to NO/NC and COM terminals
- Ensure load does not exceed 250V AC @ 10A or 30V DC @ 10A rating
Arduino resets or module behaves erratically:
- Use an external 5V power supply for the relay module
- Arduino's 5V pin may not supply sufficient current for all channels [citation:1][citation:3]
