Tsukure Mad Labs Circuit Breaker with High and Low Voltage Protection

Voltage fluctuations have always been a problem and are responsible for most of the failure in AC appliances. Be it a normal home appliance like a Toaster or a high performance industrial  machine like a CNC, everything has a rated voltage only on which it will run without any problem at its maximum efficiency. Unfortunately our Domestic/Industrial Lines fails to provide us that rated voltage due to various reasons, hence in this project we are going to build a simple electronic circuit breaker which could trigger a relay to disconnect the load when a high/low voltage detected. 

This project is designed around the famous op-amp LM358. We are going to make the op-amp work in Differential mode thus making it to compare the current voltage with a preset voltage. The whole project can be built on a bread board (except the power lines) and could be made to work in no time.

Components used in this module...

Find out more about the components used in this STEM Module.

Let's Get Started!

Below you will find a list of bits to gather before hand, followed by a detailed schematic. Using a breadboard lay out the components and connect them together as shown. Alternatively you can purchase this module from our shop and simply solder the components in the places indicated on the quality assured printed circuit boards provided.

What You Need...

1 0.1uF (100nF) Capacitor (Polarized)
1 100uF Capacitor (Polarized)
1 10uF Capacitor (Polarized)
1 Bridge Rectifier DB101 Diode
1 LM358P Integrated Circuit (IC)
1 10K
[ Brown, Black, Black, Red ]
Resistor (0.25 Watt)
1 1K
[ Brown, Black, Black, Brown ]
Resistor (0.25 Watt)
1 2K
[ Red, Black, Black, Brown ]
Resistor (0.25 Watt)
1 2K2
[ Red, Red, Black, Brown ]
Resistor (0.25 Watt)
1 5K1
[ Green, Brown, Black, Brown ]
Resistor (0.25 Watt)
2 BC547 Transistor (NPN)
1 LM7805 Voltage Regulator

NB: Any resistor colour codes specified relate to 5 band resistor codes, the 5th band has not been shown intentionally. The 5th band indicates the resistor tolerence, we use only the highest tolerence resistors in our products.

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Just An Idea!

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