Different types of conventional circuit breakers • Merits of different types of conventional circuit breakers • Modern trends Fuse • Miniature Circuit Breaker MCB • Earth-leakage circuit breaker (ELCB) • Residual Current Circuit Breaker (RCCB) • Molded Case Circuit Breaker (MCCB)

1. NAME : Ravirajsinh Solanki
ENROLLMENT NO: 150990109011
SUBJECT : Switch Gear & Protection(2170908)
TOPIC : Merits Of Different Types Of Conventional
Circuit Breakers & Modern Trends Of C.B
BRANCH: Electrical Engineering
SEM:7th
Guided By
Mrs.Jalpa Thakkar

2. CONTENT
• Different types of conventional circuit breakers
• Merits of different types of conventional circuit
breakers
• Modern trends
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3.  Different types of conventional circuit breakers
• Fuse
• Miniature Circuit Breaker MCB
• Earth-leakage circuit breaker (ELCB)
• Residual Current Circuit Breaker (RCCB)
• Molded Case Circuit Breaker (MCCB)
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4.  Advantage Of Different
Types Of Circuit Breaker
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5.  Fuse
• It is the cheapest form of protection, and it does need any
maintenance.
• Operation of fuse is simple and no complexity is involved
• The operation time of fuse can be made much smaller than operation
of circuit breaker. It is the primary protection device against short
circuits
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6. Miniature Circuit Breaker (MCB)
• MCB is more sensitive to current than fuse. It detects any abnormality in
the current flow and automatically switches off the electrical circuit.
• In case of MCB, the faulty zone of electrical circuit can be easily
identified. Faulty circuit trips to the off position. On the other hand in
case of fuse, the complete fuse wire needs to be checked by opening fuse
grip for confirming the faulty zone.
• With MCB it is very simple to resume to the supply. You just need to
push the knob of MCB back to on position. But in case of fuse, the entire
fuse wire needs to be replaced.
• Handling MCB is electrically safer than handling a fuse.
• CB is reusable and hence has less maintenance and replacement cost.
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7.  Earth-leakage circuit breaker (ELCB)
• The main purpose of ELCB is protects the animals and human from
the electrical shock.
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8.  Residual Current Circuit Breaker (RCCB)
• A ground fault circuit interrupter circuit breaker (GFCI breaker
in USA and Canada) and residual-current breaker with
overload are devices that combine the functions of a residual-
current device with a circuit breaker.
• They detect both supply imbalance and overload current.
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9.  Molded Case Circuit Breaker (MCCB)
• MCCB are compact in size ,so for this reason it saves considerable
space in panel design.
• MCCS are maintenance free.
• It can be reset & switched on again immediately after finding the
fault that caused the tripping during operation.
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10. Modern Trends Of Circuit
Breaker
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11. • According different criteria there are different types of circuit
breaker
• According to their arc quenching media the circuit breaker can be
divided as-
1. Vacuum circuit breaker.
2. SF6 circuit breaker.
3. Oil circuit breaker.
4. Air circuit breaker.
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12.  Vacuum Circuit Breaker
• A vacuum circuit breaker is such kind of circuit breaker where the arc
quenching takes place in vacuum.
• The technology is suitable for mainly medium voltage application.
• As time goes on, the size of the vacuum interrupter is being reduced
from its early 1960’s size due to different technical developments in
this field of engineering.
• The contact geometry is also improving with time, from butt contact
of early days it gradually changes to spiral shape, cup shape.
• The vacuum circuit breaker is today recognized as most reliable
current interruption technology for medium voltage switchgear.
• It requires minimum maintenance compared to other circuit breaker
technologies.
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14.  SF6 Circuit Breaker
• A circuit breaker in which the current carrying contacts operate in
sulphur hexafluoride or SF6 gas is known as an SF6 circuit breaker.
• SF6 has excellent insulating property.
• So due to its high dielectric strength and high cooling effect SF6 gas
is approximately 100 times more effective arc quenching media than
air. Due to these unique properties of this gas, SF6 circuit breaker is
used in complete range of medium voltage and high voltage
electrical power system. These circuit breakers are available for the
voltage ranges from 33KV to 800 KV and even more.
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15. • According to their services the circuit breaker can be divided as-
1. Outdoor circuit breaker
2. Indoor breaker.
• According to the operating mechanism of circuit breaker they can be
divided as-
1. Spring operated circuit breaker.
2. Hydraulic circuit breaker.
• According to the voltage level of installation types of circuit breaker
are referred as-
1. High voltage circuit breaker.
2. Medium voltage circuit breaker.
3. Low voltage circuit breaker.
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16. THANK YOU
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