Here an electronic circuit breaker is designed which is based on the current sensing across a series element typically a CT (current Transformer). The current sensed which is compared against the preset value proportional to the voltage by comparator which is inbuilt in arduino to generate an output that drives a relay through a MOSFET to trip the load very fastly. The concept of electronic circuit breaker came into focus realizing that the conventional circuit breakers such as MCBs take longer time to trip. The steadily increasing population has more demand and consumption of electric energy in the market as raised and that of equipment’s used like electrical and electronics are also costlier So to protect the electrical system from overload or short circuit here is one possibility, which is by ultrafast acting electronic circuit breaker The electronic circuit breaker is based on the voltage drop across a series element proportional to the load current, typically a low -value resistor.

1. Raghu Institute of Technology
DAKAMARRI , VISAKHAPATNAM AP 531162
Development of Electronic Circuit Breaker
BY
GANESH BEHERA
Department of Electrical And Electronics Engineering

2. Contents:
• Objective
• Abstract
• Introduction
• Difference between fuse and C. B
• About circuit breaker
• Types of circuit breaker
• Block diagram
• Working
• Advantages
• Conclusion

3. Abstract:
Here an electronic circuit breaker is designed which is based on the current
sensing across a series element typically a CT (current Transformer). The current
sensed which is compared against the preset value proportional to the voltage by
comparator which is inbuilt in arduino to generate an output that drives a relay
through a MOSFET to trip the load very fastly.
The concept of electronic circuit breaker came into focus realizing that the
conventional circuit breakers such as MCBs take longer time to trip.
The steadily increasing population has more demand and consumption of electric energy
in the market as raised and that of equipment’s used like electrical and electronics are
also costlier
So to protect the electrical system from overload or short circuit here is one possibility,
which is by ultrafast acting electronic circuit breaker
The electronic circuit breaker is based on the voltage drop across a series element
proportional to the load current, typically a low -value resistor.

4. Voltage fluctuations have always been a problem and are responsible for most of the
failure in AC appliances.
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
electronic circuit breaker which could trigger a relay to disconnect the load when a
high/low voltage detected.
The main advantage of an electronic trip circuit breaker is that response can be
configured with high precision. Conventional thermal-magnetic breakers have internal
physical components that cannot be adjusted, while the operating parameters of a
microprocessor can be reprogrammed at any time.
Perhaps the most significant difference between circuit breakers and fuses pertains to
their lifespan. You must replace a fuse once it serves its purpose, but circuit breakers
operate via a switch that you simply reset.
Introduction

5. Unlike a fuse, which operates once and then has to be replaced, a
circuit breaker can be reset (either manually or automatically) to
resume normal operation.
Basic difference between fuse and circuit breaker ?

6. Detail picture of circuit breaker

7. Parts of Circuit breaker
1. Actuator lever
2. Actuator mechanism
3. Contacts
4. terminals
5. Bimetallic strip
6. Calibration screw
7. Solenoid
8. Arc divider/extinguisher

8. Operation of circuit breaker
The primary function of an electrical circuit breaker is to provide
opening and closing of the current carrying contacts. Although it is
seems to be very simple. But we should remember, that, one circuit
breaker remains at its closed position for maximum period of its life
span. Very occasionally it is required to operate a circuit breaker for
opening and closing its contacts.
Hence, circuit breaker operation must be very reliable without any
delay or sluggishness. For achieving this reliability the circuit breaker
operating mechanism becomes more complex than it was first thought.
Why an electronic circuit breaker is used ?
In this modern world we know that advanced technologies are paramount
for the use of electrical and electronic appliances. Now this can be a house
wiring system or substations we all know that the components are
sensitive . Even though we have conventional circuit breakers , fuses and
other stuff those are time dependent and by the time it shuts down the
components will be burned so to overcome this difficulty we use elctronic
circuit breaker which gives fast response and tripping time is milliseconds.
With the help of arduino programming and other power electronic
equipments we can know the status of our circuit breaker when it is
overloaded.

9. Circuit breaker for 3 phase supply

10. 2 pole circuit breaker

11. Types of circuit breakers
• Low Voltage Circuit Breakers
• Medium Voltage Circuit Breakers
• High Voltage Circuit Breakers
• Magnetic Circuit Breakers
• Thermal Circuit Breakers

12. Thermal over current circuit breaker
Ideally suited to protect against
overcurrent and short circuit of broad range of
equipment and systems- from motors and
transforms windings, through circuit boards.to the
low voltage power distribution circuits of road
vehicles, battery powered machines.

13. • Electronic circuit breaker is based on the voltage drop across a series element
proportional to the load current, typically a low value resistor.
• This voltage is sensed and rectified to DC which is and then compared with a
preset voltage by a level comparator to generate an output that drives a relay
through a MOSFET to trip the load.
• The unit is extremely fast and overcomes the drawback of the thermal type. It
uses a ARDUINO

15. OPERATION OF ELECTRONIC
CIRCUIT BREAKER
The main power supply is given directly to load through CT and step down transformer.
230 volt is Step down to 12v and supplied to regulated supply unit which consist of bridge
rectifier to convert ac to dc and passed through 7805 regulator to get 5v supply for
working of arduino, capacitor filters are used to remove the ripples to get pure constant dc
voltage[8]. The current passing to load is sensed by the current transformer and output of
CT will be in analog form is given to the ADC pin of arduino for converting the analog
output to digital data. The current sensed is compared with the inbuilt comparator of
arduino which as pre-set reference value
If the current sensed is less than the pre-set value than MOSFET will be in OFF state and
relay will not trip the supply to load. As we increase the load current drawn is more so if
the current is increased than the pre-set value than MOSFET will turn ON and energizes
the relay. Thus LED used as an indicator is properly biased, and it glows. The relay coil
gets energized, causing the armature to shift its position to the normal open point from the
normal closed point[2]. The AC supply to the load is thus cut off from the load and the
load is tripped. Once the circuit is tripped it must be reset for further use using reset
button. In either case, the arduino is programmed so as to show the status of the output
on the LCD interfaced to it. In case of normal operation arduino will pin will receive 5v dc
from regulator and accordingly displays the status on the LCD

16. ● Debugging :- The arduino Environment provide easiest debugging environment
which is cross-platform and is accepted by every member of the family.
● No programmer or dumping flash by dirty ways,With most of the companies
already providing on-board debugger still compared to a lot of
microcontroller(8051) upload is a click away.
● Every time you don't need to take datasheet out and figure what the architecture
is what are the addresses of the microcontroller to write simple functions like
delay or interrupt.
● Design of the board is very carefully crafted for beginners be it normal Switch or
ISP header to the polarity of power,The chances are steep that you would be blow
it.
● Peripherals and Modular Design : Arduino Ecosystem has fantastic modular
design,you can simply add the already designed shields to the board with out any
wire,just plug and play with peripherals like motor shield,Bluetooth shield,Wifi and
what not already made.
● Libraries:A lot of libraries and IC's have already been build for the same which is
crucial a lot of times.
WHY ARDUINO ?

17. • Power Supply Block
• ARUDINO(Atmega 328)
• Relay
• LCD
• MOSFET
• Keil Compiler
• Language: Embedded C or Assembly.
Equipment Required
Hardware
Software

19. • This fast acting electronic circuit breaker has
very short tripping time as compared to other
circuit breakers.
• It is more efficient and reliable as compared to
other circuit breakers.
• It is less costly as compared to other circuit
breakers
.
Advantages
• Using this device fast acting electronic
circuit breaking can be achieved to save
expensive equipment from possible
damage.
• Using this unique concept a prototype can
be developed as a projects work for
electrical engineering students
Conclusion