Testing and Commissioning of Electrical Equipments (2180901) MCQs

MCQs of Installation and Commissioning of Rotating Electrical Machines

Showing 21 to 30 out of 45 Questions
1 2 3 4 5
21.
What should be the reason? Thermal overload protection operates while the motor is running
(a) Frequency very high
(b) One phase block making single phasing
(c) Ventilation not proper
(d) All of these
Answer:

Option (d)

22.
What should be the reason? Motor produce humming sound.
(a) Opening of one phase
(b) conductors shorted
(c) Earth fault
(d) All of these
Answer:

Option (d)

23.
What should be the reason? Motor runs at a slow speed
(a) Heavy overload
(b) low supply voltage
(c) High Rotor resistance (rotor starter not removed properly)
(d) All of these
Answer:

Option (d)

24.
What should be the reason? Motor runs at a very fast speed
(a) High Supply Voltage
(b) High Supply frequency
(c) Load through out
(d) All of these
Answer:

Option (d)

25.
The motor in close is used for collieries, the chemical plant is
(a) Flame proof type
(b) Splash proof type
(c) Totally enclosed type
(d) Pipe ventilated type
Answer:

Option (a)

26.
The motor enclosure used in the wood-working industry is
(a) Protected type
(b) Totally enclosed fan cooled type
(c) Flame proof type
(d) Splash proof type
Answer:

Option (b)

27.
The motor enclosure used for industrial purposes is
(a) Protected type
(b) Drip proof type
(c) Totally enclosed type
(d) Open type
Answer:

Option (a)

28.
15 minute rated motors are suitable for
(a) Light duty cranes
(b) Medium duty cranes
(c) Heavy duty cranes
(d) All of the above
Answer:

Option (a)

29.
For medium-duty cranes the short time rating motor used is
(a) 10 minutes
(b) 15 minutes
(c) 30 minutes
(d) any of the above
Answer:

Option (c)

30.
While selecting a motor for air-conditioner the feature of utmost importance is
(a) Type of enclosure
(b) Type of bearing
(c) Noise
(d) Power transmission arrangement
Answer:

Option (c)

Showing 21 to 30 out of 45 Questions
1 2 3 4 5