Quiz Questions

ITI Quiz - 21-Apr-2026 03:16 PM (ITISKILL355085)

Q-Paper A-Paper
Question 1 1 Marks
What is the use of suction baffle in a scroll compressor?
A
Reduce noise of compressor
B
Increase noise of compressor
C
Reduce capacity of compressor
D
Allow liquid to enter into compressor
Question 2 1 Marks
What is the reason for poor compression?
A
Less clearance volume
B
Scratches on the piston surface
C
Lapped valve plate and reed seat
D
Good lubrication on the moving parts
Question 3 1 Marks
Where the refrigerant vapour is compressed in scroll compressor?
A
Fixed and reciprocating scroll
B
Between fixed and orbiting scrolls
C
Crank and connecting rod
D
Eccentric and cylinder
Question 4 1 Marks
Which cooling medium is used to cool the motor of a hermetic reciprocating compressor in AC?
A
Discharge vapour
B
Liquid refrigerant
C
Suction vapour
D
Water
Question 5 1 Marks
Which instrument is used to identify the
terminals of a compressor motor?
A
Ammeter
B
Voltmeter
C
Ohm meter
D
Anemometer
Question 6 1 Marks
Which is used to connect the rotor bars in 3phase squirrel cage induction motor?
A
Screw
B
Welded
C
End ring
D
Nut and bolt
Question 7 1 Marks
Which part connects the piston with small end of connecting rod in a reciprocating compressor?
A
Piston pin
B
Piston bolt
C
Piston rings
D
Piston sleeve
Question 8 1 Marks
What is the use of capacitor in PSC
operated induction motor?
A
Decrease the starting torque
B
Cancel the starting torque
C
Improve the power factor
D
Decrease the power factor
Question 9 1 Marks
Which capacitor is disconnected by relay in capacitor start and induction run motor?
A
Starting capacitor
B
Running capacitor
C
Boosting capacitor
D
Power factor correction capacitor
Question 10 1 Marks
What is the physical condition of refrigerant
in hermetic dome of rotary compressor?
A
LP Liquid
B
HP Liquid
C
HP Vapour
D
LP Vapour
Question 11 1 Marks
What is the cause for frequent tripping of circuit breaker while starting a single phase motor?
A
Winding open
B
Winding short
C
Motor belt removed
D
No load on the motor
Question 12 1 Marks
Which winding is made of thick wire in single phase induction motor?
A
Starting
B
Running
C
Auxiliary
D
Additional
Question 13 1 Marks
Which type of compressor is used for domestic refrigerator?
A
Semi sealed compressor
B
Centrifugal compressor
C
Hermetic compressor
D
Open type compressor
Question 14 1 Marks
Which motor has the least starting
torque?
A
CSIR
B
CSR
C
RSIR
D
PSC
Question 15 1 Marks
Which lubricant oil is used in swash plate of R 134a compressor?
A
Servo 20
B
POE
C
SAE - 40
D
Mineral oil
Question 16 1 Marks
Which motor has the least starting
torque?
A
CSIR
B
CSR
C
RSIR
D
PSC
Question 17 1 Marks
Why the top of dome is hot in a scroll compressor?
A
Discharge plenum is at top
B
Suction super heat is less
C
Suction gas not cooled
D
Undercharged system
Question 18 1 Marks
What is the reason for swash plate compressor failure in car AC?
A
Oil level is low
B
Oil level is medium
C
Thermostat not working
D
Refrigerant charge normal
Question 19 1 Marks
Which movement of the scroll compresses the low pressure vapour in scroll compressor?
A
Reciprocating
B
Centrifugal
C
Rotating
D
Orbital
Question 20 1 Marks
Which winding is made of thin wire in single phase motor?
A
Main
B
Series
C
Starting
D
Running
Question 21 1 Marks
Which is disconnected by centrifugal switch is RSIR motor?
A
Running winding
B
Common winding
C
Starting winding
D
Running capacitor
Question 22 1 Marks
Which gas is used for pressure testing the compressor dome?
A
Air
B
Oxygen
C
Nitrogen
D
Refrigerant
Question 23 1 Marks
How the difference between the
synchronous speed and the actual rotor speed is
specified?
A
Lead
B
Lag
C
Slip
D
Trip
Question 24 1 Marks
What is the formula to find out the
synchronous speed of induction motor?
A
Ns=(150P/f)
B
Ns=(120f/P)
C
Ns=(150f/P)
D
Ns=(120P/f)
Question 25 1 Marks
What is the method of starting a 3 phase slip ring induction motor?
A
With starting relay
B
Using starting capacitor
C
With running capacitor
D
Adding resistance to rotor winding
Question 26 1 Marks
How to change the direction of rotation in
3 Phase induction motor?
A
Change neutral
B
Change all phase
C
Change any two phase
D
Change the winding only
Question 27 1 Marks
What is the temperature set in thermostat that stops the compressor motor?
A
Cut in
B
Range
C
Cut out
D
Differential
Question 28 1 Marks
Which valve is closed during compression stroke in reciprocating compressor?
A
Service valve
B
Liquid line valve
C
Discharge valve
D
Suction valve
Question 29 1 Marks
What is the revolving part of induction motor?
A
Stator
B
Rotor
C
Relay
D
Winding
Question 30 1 Marks
Which is a positive displacement
compressor?
A
Centrifugal compressor
B
Scroll compressor
C
Water pump
D
Oil pump
Question 31 1 Marks
Which type of rotor is used in 3 Phase induction motor?
A
Squirrel cage rotor
B
Shaded pole rotor
C
Laminated rotor
D
Solid rotor
Question 32 1 Marks
What is the advantage of a hermetically sealed compressor in refrigerator?
A
Silent operation
B
Easily serviceable
C
Noise is more
D
Cost is high
Question 33 1 Marks
What is the use of a starting capacitor in single phase induction motor?
A
Improve power factor
B
Increase starting torque
C
Decrease starting torque
D
Dis connect starting winding
Question 34 1 Marks
What is the effect of moist air present inside the hermetic system?
A
Capacity of compressor will increase
B
Less wear and tear in compressor
C
Harmful to the compressor and motor
D
Increase the life of compressor