Switchgear Protections Multiple Choice Questions and Answers Preparation for Competition exams pdf

1.    The main function of a fuse is to
(a)     protect the line
(b)     open the circuit
(c)    protect the appliance
(d)    prevent excessive currents
(e)    none of the above
Ans: d

2.    On which of the following routine tests are conducted ?
(a)    Oil circuit breakers
(b)    Air blast circuit breakers
(c)    Minimum oil circuit breakers
(d)    All of the above
Ans: d
3.    SF6 gas
(a)    is yellow in colour
(b)    is lighter than air
(c)    is nontoxic
(d)    has pungent small
(e)    none of the above
Ans: c
 
4. The arcing contacts in a circuit breaker are made of
(a)     copper tungsten alloy
(b)     porcelain
(c)    electrolytic copper
(d)    aluminium alloy
Ans: a

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

6. With which of the following, a circuit breaker must be equipped for remote operation ?
(a) Inverse time trip
(b) Time-delay trip
(c) Shunt trip   
(d) None of the above
(e) All of the above
Ans: c

7.    Fault diverters are basically
(a) fuses   
(b) relays
(c) fast switches    
(d) circuit breakers
Ans: c

8.    A thermal protection switch can protect against
(a) short-circuit     
(b) temperature
(c) overload   
(d) over voltage
Ans: c

9.    Arc in a circuit behaves as
(a)     a capackive reactance
(b)     an inductive reactance
(c)    a resistance increasing with voltage rise across the arc
(d)    a resistance decreasing with voltage rise across the arc
Ans: d

10.    Thermal circuit breaker has
(a)    delayed trip action
(b)    instantaneous trip action
(c)    both of the above
(d)    none of the above
Ans: a

Read More Switchgear Protections Questions and Answers => Click Here