4 CHANNEL RELAY MODULE (VEL18E)

• Voltage (control): 5V DC
• Channels: 4 independent relays
• Max load per channel:
  • 10A @ 250V AC
  • 10A @ 30V DC
• Trigger: Usually LOW-level (active LOW)
• Inputs: IN1, IN2, IN3, IN4
• Outputs: NO / NC / COM terminals
• Indicator LEDs: One per relay
• Compatibility: Arduino, Raspberry Pi, PIC, etc.

🧠 Quick Explanation

• Each channel works like a switch controlled by your microcontroller
• You can control 4 separate devices (lights, pumps, motors, etc.)
• The 10A rating is per relay, not shared

⚠️ Important Tips

• Use a stable 5V power supply (relays draw ~15–20mA each)
• For safety:
  • Don’t exceed 10A per channel
  • Be careful with AC mains (220V)
• Many boards have opto-isolation → protects your microcontroller