NEB Class 12 Science Switch Gear and Protection Question Paper 2082 (Set D)
Group 'A' (Multiple choice questions)
Rewrite the correct option of each question in your answer sheet.
The earth fault involves
The arcing contacts in a circuit breaker are made of
A thermal trip in MCB is used for protection against
The single unit of vacuum circuit breaker can be used for voltage up to
Drop out fuse is generally used for
What is the purpose of secondary winding in current transformer?
A potential transformer (PT) is connected in ............ with the line.
The fault clearing time of a circuit breaker is usually
Faulty condition in a power system is firstly sensed by
Group 'B' (Short answer questions)
Attempt all the questions.
Define fuse and fusing current. Write four advantages and two disadvantages of fuse.
Define switch gear. Explain construction and working principle of a contractor.
Explain the construction and working principle of potential transformer.
What are the errors that occur in current transformer (CT)? Explain. Also write the error reducing techniques in CT.
Define relay. Mention the types of electromagnetic relay and explain any one of them in detail.
Group 'C' (Long answer questions)
Attempt all the questions.
Mention few duties of circuit breaker and explain the working principle of oil circuit breaker (OCB) along with its construction details.
List out the different types of faults in alternator. Explain the differential protection scheme for a generator.