Arduino Aquaponics: Relays

Introduction

One way to take any Arduino project to the next level is by using relays.  Relays are essentially mechanical switches, except they are electrically controlled and, therefore, can be controlled by an Arduino.  Many devices used in aquaponics have on/off states, such as pumps, grow lights and fans and therefore can be controlled with a relay.  This project will simply turn the relay package "on" and "off" without hooking up any additional hardware (like an aquaponics pump); we'll save that for other specific tutorials.

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