Busbar

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Busbar

A busbar in electrical power distribution refers to thick strips of copper

Copper

Copper is a chemical element with the symbol Cu and atomic number 29.It is a ductile metal with very high thermal and electrical conductivity....
or aluminium

Aluminium

Aluminium or aluminum is a silvery white and ductile member of the boron group of chemical elements. It has the symbol Al; its atomic number is 13....
that conduct electricity

Electricity

Electricity is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena such as lightning and static electricity, but in addition, less familiar concepts such as the electromagnetic field and electromagnetic induction....
within a switchboard

Electric switchboard

An electric switchboard is a device that directs electricity from one source to another. It is an assembly of panels, each of which contain switches that allow electricity to be redirected....
, distribution board

Distribution board

A distribution board is a component of an electricity supply system which divides an electrical power feed into subsidiary Circuit , while providing a protective Fuse or circuit breaker for each circuit, in a common Enclosure ....
, substation, or other electrical apparatus.

The size of the busbar is important in determining the maximum amount of current that can be safely carried.

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plz. send me total description about busbar arrengments and i6ts protection

What is the factor that decides the minimum spacing to be kept between phases of an Isolated phase g...

Encyclopedia

A busbar in electrical power distribution refers to thick strips of copper

Copper

Copper is a chemical element with the symbol Cu and atomic number 29.It is a ductile metal with very high thermal and electrical conductivity....
or aluminium

Aluminium

Aluminium or aluminum is a silvery white and ductile member of the boron group of chemical elements. It has the symbol Al; its atomic number is 13....
that conduct electricity

Electricity

Electric switchboard

Distribution board

Electrical substation

An electrical substation is a subsidiary station of an electricity Electrical generation, electric power transmission and electricity distribution system where voltage is transformed from high to low or the reverse using transformers....
s may use metal tubes of 50 mm in diameter (1,000 mm²) or more as busbars.

Busbars are typically either flat strips or hollow tubes as these shapes allow heat

Heat

In physics and thermodynamics, heat is any transfer of energy from one body or thermodynamic system to another due to a difference in temperature....
to dissipate more efficiently due to their high surface area

Surface area

Surface area is how much exposed area an object has. It is expressed in square units. If an object has flat Face , its surface area can be calculated by adding together the areas of its faces....
to cross-sectional

Cross section (geometry)

In geometry, a cross-section is the intersection of a body in 2-dimensional space with a line, or of a body in 3-dimensional space with a plane, etc....
area ratio

Ratio

A ratio is an expression which compares quantities relative to each other. The most common examples involve two quantities, but in theory any number of quantities can be compared....
. The skin effect

Skin effect

The skin effect is the tendency of an alternating current to distribute itself within a Conductor so that the current density near the surface of the conductor is greater than that at its core....
makes 50-60 Hz AC

Alternating current

In alternating current the movement of electric charge periodically reverses direction. An electric charge would for instance move forward, then backward, then forward, then backward, over and over again....
busbars more than about 8 mm (1/3 in) thick inefficient, so hollow or flat shapes are prevalent in higher current applications. A hollow section has higher stiffness than a solid rod, which allows a greater span between busbar supports in outdoor switchyards.

A busbar may either be supported on insulators, or else insulation may completely surround it. Busbars are protected from accidental contact either by a metal enclosure or by elevation out of normal reach. Neutral

Ground and neutral

Since the neutral point of an electrical power system is often connected to earth ground , ground and neutral are closely related. Under certain conditions, a Electrical conduction used to connect to a system neutral is also used for grounding of equipment and structures....
busbars are typically bolted directly onto any metal chassis of their enclosure. Busbars may be enclosed in a metal housing, in the form of bus duct or busway, segregated-phase bus, or isolated-phase bus

Isolated-phase bus

In electrical engineering, isolated-phase bus, also known as Phase-isolated Bus in some countries, is a method of construction for circuits carrying very large currents, typically between a generator and its step-up transformer in a steam or large hydroelectric power plant....
.

Busbars may be connected to each other and to electrical apparatus by bolted or clamp connections. Often joints between high-current bus sections have matching surfaces that are silver-plated to reduce the contact resistance. At extra-high voltages (more than 300 kV) in outdoor buses, corona

Corona discharge

In electricity, a corona discharge is an electrical discharge brought on by the ionization of a fluid surrounding a conductor , which occurs when the potential gradient exceeds a certain value, but conditions are insufficient to cause complete electrical breakdown or electric arc....
around the connections becomes a source of radio-frequency interference and power loss, so connection fittings designed for these voltages are used.

Protection

Busbars are vital parts of a power system and so a fault should be cleared as fast as possible. A busbar must have its own protection, although they have high degrees of reliability. Bearing in mind the risk of unnecessary trips, the protection should be dependable, selective and should be stable for external faults, called 'through faults'.

The most common fault is phase to ground, which usually results from human error.

There are many types of relay

Relay

A relay is an electrical switch that opens and closes under the control of another electrical circuit. In the original form, the switch is operated by an magnet to open or close one or many sets of contacts....
ing principles used in busbar

A special attention should be made to current transformer

Current transformer

In electrical engineering, a current transformer is used for measurement of electric currents. Current transformers are also known as instrument transformers....
selection since measuring errors need to be considered.