Sometimes, it is good to know when the power is out at your house. And this will help because it will notify you (by beeping until you make it stop)Therefore letting you know that the power is out. This is useful because if you are asleep and the circuit is in the other room this will let you know what to prepare for what might happen.

Step 1: What You Need:

For this project you will need:

Arduino Uno R3

3 LEDs of 3 different colors

1 2.2k ohm resistor

3 220 ohm resistors

1 Photoresistor (LDR)

1 buzzer (Piezo small)

7 wires of your choice

Step 2: Assembly

Here is a guide of how to build this circuit(Code and diagram).

PowerOutageAlarm.ino
Download

Step 3: Setup

This is the step which that we keep our alarm somewhere to stay.

You will need:

a battery pack

an artificial light source (keep it on)

Now, plug in your battery pack to your Arduino Uno and then turn on your light that the circuit is placed next to.

It should do nothing, that is good! Now turn off the light. Your circuit should light up and beep at the same time repeatedly, this means your circuit works!