In this quick Arduino tutorial I will explain how you can control a relay using the Arduino Board, one 1K and one 10K resistors, 1 BC547 transistor, one 6V or 12V relay, one 1N4007 diode and a 12V fan ...

Want to control high-power devices with a microcontroller? These relay modules are super handy. You get two identical boards, each with 8 relays. Each relay can switch up to 10A at 250V AC or 30V DC – ...