Miniature Circuit Breaker

Q. (a) Draw the symbols to represent the following components of electrical circuits: cell, bulb, switch in the ‘ON’ position, switch in the ‘OFF’ position and battery.

(b) An electrician is doing some repairs in your house. He wants to replace a fuse by a piece of wire. Would you agree? Give reasons for your response. [5 MARKS]

Q. (a) What does MCB stand for? Explain the working of MCBs. Why are they preferred over fuses?

(b) Name the principle on which electric fuse works?
[3 MARKS]

Q. Pictures of various kinds of fuses and there uses?

Q. Generally, MCBs are designed to protect the household appliances from high _________.

1. dust
2. current
3. heat
4. light

Q. Which of the following is/are advantage(s) of a Miniature Circuit Breaker?

1. It automatically breaks the circuit if there is overheating.
2. It needs to be replaced after every single operation.
3. It can be manually or automatically reset.
4. It protects the appliances from large amounts of current.

Q. Which of the following is a disadvantage of a Miniature Circuit Breaker?

1. 
   It automatically breaks the circuit if there is overheating.
2. 
   It needs to be replaced after every single operation.
3. 
   It can be manually or automatically reset.
4. 
   It protects the appliances from large amounts of current.

Q. What is/are the advantage of MCB over fuses?

1. Its wire melts unlike fuses wire
2. It automatically turn off to save from excess electricity
3. None of these
4. It takes less time to break the circuit as compare to fuse while overloading

Q. In an household electrical circuit:
a) Where is the MCB ( Miniature Circuit Breaker ) connected?
b) What is the function of ELCB ( Earth Leakage Circuit Breaker )?

Q. What is the full form of MCB?

1. Micro Circuit Breakers
2. Miniature Circuit Breakers
3. Miniature Circuit Builders
4. Mega Circuit Blockers

Q. Choose the wrong option regarding miniature circuit breaker (MCB)?

1. Quick restoration of an MCB is possible just by switching on the operation when a breakdown occurs due to the current overload
2. MCB switches off the circuit automatically when the current passing through it exceeds a certain value
3. None of the above
4. MCB contains a metal that melts when the current passing through it exceeds a certain value and hence opens the circuit

Q. What is the advantage of replacing a fuse with a circuit breaker

Q. The circuit breaker device which can be used in place of a fuse is called

1. CBD
2. MCB
3. MCD
4. CBF

Q. MCB stands for:

1. Main circuit board
2. Master code bill
3. Miniature circuit breaker
4. None of these

Q. In which of the following cases, an MCB operates to break the circuit?

1. Underloading
2. Overloading
3. Short circuit
4. Faulty circuit design

Q.

What is a miniature circuit breaker?

Q. Which of the following is the function of MCB in household circuit?

1. This switch automatically turns off when current exceeds safe limit
2. This switch automatically turns on when current exceeds safe limit
3. Saves the electrical appliances from getting damaged due to excess current
4. Saves from short-circuiting

Q. Which of the following is/are advantage(s) of a Miniature Circuit Breaker?

1. It automatically breaks the circuit if there is overheating.
2. It needs to be replaced after every single operation.
3. It can be manually or automatically reset.
4. It protects the appliances from large amounts of current.

Q. An MCB functions basically as an electric switch.

1. False
2. True

Q. An MCB is always a better alternative to a safety fuse.

1. False
2. True

Q. Pick the safety device used in domestic electric circuits.

1. Battery
2. MCB
3. CFL
4. Switch

Q. In an electric circuit, MCB stands for:

1. Mother Control Board
2. Miniature Circuit Breaker
3. Mega Circuit Breaker
4. Main Circuit Board

Q. An MCB is always a better alternative to a safety fuse.

1. False
2. True