ELECTRICIAN 2nd YEAR MODULE – Circuit Breakers and Relays ONLINE TEST

Question 1 of 15

1. What is the cause for the defect if phase to ground fault on the transmission line?

Fuse failure

Insulation failure

Human error

Components failure

Question 1 of 15

Question 2 of 15

2. How the rupturing capacity of circuit breaker is rated?

KV

KW

MVA

KVAR

Question 2 of 15

Question 3 of 15

3. What is the function of Buchholz relay in power transformer?

Over load and short circuit protection

Over voltage and earth fault protection

Open circuit and earth fault protection

Open circuit and over voltage protection

Question 3 of 15

Question 4 of 15

4. Which type of load is protected by 'G' series MCB?

Ovens

Air conditioners

General lighting systems

Geysers

Question 4 of 15

Question 5 of 15

5. Which circuit breaker is used as a switch and protective device in the domestic wiring circuit?

Moulded case circuit breaker

Miniature circuit breaker

Air circuit breaker

Earth Leakage circuit breaker

Question 5 of 15

Question 6 of 15

6. Which relay hold their contacts in position after power is cutoff?

Latching relay

Voltage relay

Current relay

Reed relay

Question 6 of 15

Question 7 of 15

7. What is the name of circuit breaker?

Air blast circuit breaker

Vacuum circuit breaker

Air break circuit breaker

Oil circuit breaker

Question 7 of 15

Question 8 of 15

8. What is the pick-up voltage in a over voltage relay indicated?

Minimum voltage rating of relay

Minimum voltage to start the relay

Maximum voltage rating of relay

Working voltage of relay

Question 8 of 15

Question 9 of 15

9. What is the purpose of trip coil used in circuit breakers?

Emergency operation

Remote operation

Easy operation

Accurate operation

Question 9 of 15

Question 10 of 15

10. Which type of relay is used in both A.C and D.C supply?

Reed relay

Thermal relay

Impulse relay

Clapper-type armature relay

Question 10 of 15

Question 11 of 15

11. What is the effect, if the test button marked as 'X' is closed permanently in ELCB?

Circuit trips intermittently

Circuit will not trip on leakage

Circuit switch off completely

Circuit functions normally

Question 11 of 15

Question 12 of 15

12. What is the defect in a oil circuit breaker if the oil heats up excessively?

Defective tripping mechanism

Poor dielectric strength

Excessive load

Line voltage is too high

Question 12 of 15

Question 13 of 15

13. What is the function of relay to the breaking operation of circuit breaker in control circuit?

Interpreting the fault situation to operate breaker

Controlling the Speed in case of fault

Analyzing the condition of breaker

Sensing the fault quantities

Question 13 of 15

Question 14 of 15

14. Which circuit breaker is installed along with wiring circuit against leakage current protection?

MCCB

MCB

OCB

ELCB

Question 14 of 15

Question 15 of 15

15. What is the defect in an air circuit breaker, if trips intermittently on loading?

Insufficient air pressure

Incorrect setting of relay

Excessive heat

Line voltage is too high

Question 15 of 15