Low power relays boards are one of the most common interfaces between a Arduino/Raspberry Pi and the outside world. These relay boards provides electrical isolation between the low voltage circuits of the Arduino/Raspberry Pi and the high voltage loads. So why this I2C relay board? i2c relay boards only requires 4 pins from Arduino/Raspberry pi to control up to 128 relay. Raspberry Pi i2c Example of controlling i2c relay board from Raspberry Pi 1 – +5V 2 – GND (common…