MCQ on Control and Protection 4
1. The acting contacts for circuit breakers are made of:
a. stainless steel
b. hard press iron
c. copper tungsten alloy
d. porcelain
2. A fuse wire should have :
a. Low specific resistance and high melting point
b. High specific resistance and low melting point
c. High specific resistance and high melting point
d. Low specific resistance and low melting point
3. Fuse protection is used for current ratings up to:
a. 10 amp
b. 20 amp
c. 50 amp
d. 100 amp
4. A material best for fuse wire is:
a. silver wire
b. copper wire
c. lead wire
d. aluminuim wire
5. HRC fuse provides best protection in case of:
a. open circuits
b. short circuits
c. overloads
d. all of the above
6. which of the following elements serves as a protection against overload?
a. Fuse
b. Switch
c. Resistor
d. Relay
7. A PT is connected in:
a. series with the line
b. parallel with the line
c. both a and b
d. none of the above
Also view: MCQ on Control and Protection
8. A CT is connected in:
a. series with the line
b. parallel with the line
c. both a and b
d. none of the above
9. A fuse is normally a:
a. current limiting device
b. power factor correcting device
c. voltage limiting device
d. power limiting device
10. Buchholz relay is operated by:
a. gas pressure
b. eddy currents
c. electromagnetic induction
d. electro static induction
In a circuit breaker the time duration from the instant faults to the extinction of arc is known as:
a. lead time
b. lag time
c. operation time
d. total clearing time
In a circuit breaker the time duration from the instant faults to the instant of closing of contact is know as:
a. gross time
b. re-closing time
c. total time
d. operation time
Also View: MCQ on Control and Protection 3