Top 250+ Solved Testing and Commissioning of Electrical Equipment’s MCQ Questions Answer
Q. The transient voltages that appears across the contacts at the instant of arcextinction is called ..............voltage
a. Supply
b. Recovery
c. Restriking
d. Peak
Q. The power loss is an important factor for the design of
a. Transmission line
b. Motor
c. Generator
d. Feeder
Q. SF6 gas is transported in
a. Air cylinders
b. Gas cylinders
c. Liquid from in cylinders
d. Solid form in boxes
Q. The short-circuit in any winding of the transformer is the result of
a. Mechanical vibration
b. Insulation failure
c. Loose connection
d. Impulse voltage
Q. The actuating quantity for the relays may be
a. Magnitude
b. Frequency
c. Phase angle
d. Any of the above
Q. The operating speed of a relay depends upon the
a. Rate of flux built up
b. Armature core air gap
c. Spring tension
d. All of these
Q. Inverse time current relays are used for the protection of
a. Feeders
b. Transformers
c. Alternators
d. Both A and B
Q. IDMT relays are used to protect the power transformers against
a. External short-circuit
b. Over loads
c. Internal short-circuits
d. Both A and B
Q. In distance protection, the relay measures
a. Negative sequence impedance of the light from relay up to the fault point
b. Positive sequence impedance of the line from relay up to the fault point
c. Self impedance of the line from relay up to the fault point
d. Zero sequence impedance of the line from relay up to the fault point
Q. The relay used for phase fault protection of short transmission lines is
a. Reactance relay
b. Impedance relay
c. Mho relay
d. IDMT relay
Q. Where severe synchronising swing occur, the relay employed is
a. Impedance relay
b. Mho relay
c. Reactance relay
d. Induction relay
Q. For the protection of lines against faults involving variable fault resistance, thepreferred relaying scheme is a
a. Plain impedance relay
b. Directional over-current relay
c. Mho relay
d. Reactance relay
Q. For ground fault we prefer
a. Plain impedance relay
b. Directional over current relay
c. Mho relay
d. Reactance relay