Circuit Breakers & Their Characteristics

Which component in the circuit breaker is responsible for suppressing arcs?

• arc chute or arc extinguishing device.

• circuit breaker handle

• circuit breaker casing.

• circuit breaker terminal.

As current flows through the bimetallic strip, what happens to it?

• It melts

• It bends

• It breaks

• It remains unchanged

What does the rated current (I n) indicate in the circuit breaker diagram?

• The maximum current the circuit breaker can carry without tripping.

• The voltage level at which the circuit breaker operates.

• The frequency of the electrical supply.

• The power rating of the circuit breaker.

Which part of the circuit breaker indicates its status?

• Status indicator

• Power switch

• Reset button

• Fuse holder

What is the function of the switch lever in the circuit breaker?

• To manually open or close the circuit

• To increase the voltage in the circuit

• To decrease the current in the circuit

• To provide a backup power source

How many different ways are there of tripping a modern circuit breaker?

• 1

• 2

• 3

• 4

For motors and transformers, a type K circuit breaker should be used. Is this statement true or false?

• True

• False

What is the nominal tripping current advised by the label on this circuit breaker? Give your answer in amps.

• 16 A

• 10 A

• 20 A

• 25 A

Which symbol shows a circuit breaker?

• 
• 
• 
• 

What happens when a circuit breaker trips?

• The current flow doubles

• The voltage increases

• The circuit opens, stopping the current flow

• The circuit remains closed