5V Single-Channel Relay Module with Optocoupler
High-Power Switching Module for Microcontroller Control
This singlechannel relay module enables a microcontroller to independently control one highpower device such as lights, motors, and solenoids[citation:1]. It provides complete electrical isolation between the lowvoltage control circuit and the highpower load circuit, protecting your microcontroller[citation:1].
Controls 1 AC/DC Load - Switch up to 250V AC @ 10A or 30V DC @ 10A[citation:3][citation:8]
Optocoupler Isolation Provides excellent antiinterference and protects the control circuit[citation:3]
Operating voltage is 5V DC with each channel requiring 5mA trigger current[citation:3][citation:8]
Total module operating current is approximately 190mA when the relay is active[citation:6]
The module can be set to active HIGH or active LOW via a jumper on some versions[citation:3]
Technical Specifications
| Parameter | Value |
|---|
| Operating Voltage | 5V DC[citation:1] |
| Trigger Current | 5mA[citation:3] |
| Active Current | ~190mA[citation:6] |
| Maximum Load (AC) | 250V @ 10A[citation:3][citation:8] |
| Maximum Load (DC) | 30V @ 10A[citation:3][citation:8] |
| Isolation | Optocoupler[citation:3] |
| Dimensions | ~50mm x 26mm[citation:6] |
= Pin Configuration =
*Input Pins (Control Side):*
- VCC: 5V DC power supply[citation:1]
- GND: Ground connection[citation:1]
- IN: Control pin for the relay (LOW or HIGH trigger)[citation:1]
*Output Terminals (Load Side)[citation:1]:*
- COM: Common terminal
- NO (Normally Open): Load connects here when relay is activated
- NC (Normally Closed): Load connects here when relay is deactivated
On many modules, a LOW signal (0V) on IN activates the relay[citation:2][citation:9]
Some modules have a jumper to select high or low trigger[citation:3]
Applications
- Home automation (lights, fans, appliances)[citation:1]
- Industrial control systems[citation:1]
- Robotics and IoT projects
- Security systems (alarms, locks)
Versatile Control Manage highpower devices with microcontroller logic
Wide Compatibility - Works with Arduino, ESP32, Raspberry Pi, and other microcontrollers[citation:2]
√ Each relay has an independent LED status indicator for monitoring[citation:1]
√ Standard screw terminals for easy load wiring[citation:1]
√ Includes flyback diode for protection against voltage spikes[citation:1]
Troubleshooting
Relay not activating:
- Ensure the module is powered with a stable 5V DC supply
- Check if your module is active LOW or HIGH using a multimeter
- Verify signal logic matches the module's configuration
Load not switching:
- Verify wiring to NO/NC and COM terminals[citation:1]
- Ensure load does not exceed 250V AC @ 10A or 30V DC @ 10A rating[citation:3]
Arduino resets or module behaves erratically:
- Use an external 5V power supply for the relay module[citation:1]
- The Arduino's 5V pin may not supply sufficient current for reliable operation
