Which of the following medium is employed for extinction of arc in air circuit breaker ?

Which of the following medium is employed for extinction of arc in air circuit breaker ?
(a) Water 
(b) Oil
(c) Air 
(d) SF6

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1 Answer

Answer :

Which of the following medium is employed for extinction of arc in air circuit breaker ?
(a) Water 
(b) Oil
(c) Air 
(d) SF6

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Related questions

Which of the following medium is employed for extinction of arc in air circuit breaker ? (a) Water (b) Oil (c) Air (d) SF6

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Last Answer : (c) Air

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Description : The arc temperature in Oil Circuit Breaker may reach up to_______.  (A) 5,000° K (B) 8,000° K (C) 10,000° K (D) None of the above

Last Answer : The arc temperature in Oil Circuit Breaker may reach up to 5,000° K 

Arc in a circuit breaker is interrupted at?

Last Answer : Arc in a circuit breaker is interrupted at zero current.

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Last Answer : The arc voltage produced in A.C. circuit breaker is always in phase with the arc current.

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Last Answer : Air break circuit breaker Oil circuit breaker Minimum oil circuit breaker Air blast circuit breaker SF6 circuit breaker Vacuum circuit breaker

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Last Answer : Arc Extinction Process: During fault condition, when the tripping mechanism operates the circuit breaker to open its contacts, arc is produced between the contacts. There are two methods of arc ... contact space increases to such an extent that the arc does not continue after current zero.

Which of the following is used in a circuit breaker as the medium in which the arc forms?

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Last Answer : Air blast circuit breaker is used for repeated duty.

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Last Answer : Arc in a circuit behaves as a resistance decreasing with voltage rise across the arc.

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Last Answer : Answer: B

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The arc voltage in a circuit breaker is :

Description : The arc voltage in a circuit breaker is :

Last Answer : The arc voltage in a circuit breaker is : in phase with the arc current

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Last Answer : Construction of SF6 Circuit Breaker : A sulphur hexafluoride (SF6) circuit breaker consists of fixed and moving contacts enclosed in a chamber. The chamber is called arc interruption ... contact, moving contact and arcing horn are coated with a copper-tungsten arc-resistant material. 

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Explain construction and working of SF6 circuit breaker.

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With which of the following, a circuit breaker must be equipped for remote operation ?

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Last Answer : Earth Leakage circuit breaker (ELCB) works on the basis of Residual current

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A circuit breaker is designed to protect an electrical circuit from damage caused by :

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Description : ln a minimum oil circuit breaker the oil is used

Last Answer : ln a minimum oil circuit breaker the oil is used to act as circuit breaking medium only

In a circuit breaker the basic problem is to?

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Last Answer : The voltage appearing across the contacts after opening of the circuit breaker is called recovery voltage.

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Thermal circuit breaker has?

Last Answer : Thermal circuit breaker has delayed trip action.

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Last Answer : The arcing contacts in a circuit breaker are made of copper tungsten alloy.

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Last Answer : SF6 is Sulpher hexa Fluoride gas. If this gas is used as arc quenching medium in a Circuit breaker means SF6 CB.

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Description : In the illustration, the purpose of part B is to _________. EL-0033 A. increase resistance in series with the contacts as they close to prevent arcing B. create a magnetic field in the steel ... event of an overload D. provide ventilation to the contact when the breaker is close to rated capacity

Last Answer : Answer: B

A molded-case breaker provides protection against short circuits by using a/an ____________. A. shading coil B. arc quencher C. electromagnet D. holding coil

Description : A molded-case breaker provides protection against short circuits by using a/an ____________. A. shading coil B. arc quencher C. electromagnet D. holding coil

Last Answer : Answer: C

How arc is quenched in Generator Field Breaker?

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Which of the following mainly decides the current to be employed is arc welding? (A) Electrode size (B) Plate thickness (C) Voltage across the arc (D) Welded portion length

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Last Answer : (A) Electrode size

Another method of locating points on a map besides the longitude and latitude method which is frequently employed in the western states is known as the: w) Arc Method x) Tier and Range System y) Square Similar Method z) none of these

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Last Answer : ANSWER: X -- TIER AND RANGE SYSTEM

Reactance relays are employed for Phase faults in :

Description : Reactance relays are employed for Phase faults in : (A) Short lines (B) Medium lines (C) Long lines (D) Any line

Last Answer : Reactance relays are employed for Phase faults in : Short lines

Oil switches are employed for?

Last Answer : Oil switches are employed for high voltages and large currents circuits.

Which of the following busbar arrangement is generally employed in distribution system: a) One-and-half breaker arrangement b) Main and transfer arrangement c) Ring main distribution system d) Single busbar arrangement system

Description : Which of the following busbar arrangement is generally employed in distribution system: a) One-and-half breaker arrangement b) Main and transfer arrangement c) Ring main distribution system d) Single busbar arrangement system

Last Answer : Ans: C

Air blast circuit breakers for 400 kV power system are designed to operate in?

Last Answer : Air blast circuit breakers for 400 kV power system are designed to operate in 50 millisecond.

The current zero interruption, in oil and air blast circuit breakers, is achieved by?

Description : The current zero interruption, in oil and air blast circuit breakers, is achieved by?

Last Answer : The current zero interruption, in oil and air blast circuit breakers, is achieved by lengthening of the gap, cooling and blast effect.

What are the demerits of using oil as an arc quenching medium?

Description : What are the demerits of using oil as an arc quenching medium?

Last Answer : • The air has relatively inferior arc quenching properties • The air blast circuit breakers are very sensitive to variations in the rate of rise of restriking voltage • Maintenance is required for the compression plant which supplies the air blast

What are the hazards imposed by oil when it is used as an arc quenching medium?

Description : What are the hazards imposed by oil when it is used as an arc quenching medium?

Last Answer : There is a risk of fire since it is inflammable. It may form an explosive mixture with arc. So oil is preferred as an arc quenching medium.

What are the advantages of oil as arc quenching medium?

Description : What are the advantages of oil as arc quenching medium?

Last Answer : • It absorbs the arc energy to decompose the oil into gases, which have excellent cooling properties • It acts as an insulator and permits smaller clearance between line conductors and earthed components