SUPARCO Assistant Manager Electrical Power Past Papers Solved

SUPARCO Assistant Manager Electrical Power Past Papers Solved 2021

The following multiple-choice questions are from the SUPARCO Assistant Manager Electrical Power Test conducted on 2021. These questions cover a range of topics relevant to electrical engineering, and they are essential for candidates preparing for positions at the SUPARCO . The bolded question statements aim to facilitate easy navigation, providing a comprehensive review of key concepts necessary for success in the Electrical Engineer/Electronics examination.

1) As a matter of economy, voltage for power transmission should be

1. low
2. medium
3. high
4. none of above
5. The greatest eddy current loss occurs in the __ of a dc machine
6. field poles
7. commutating process
8. yoke
9. armature
10. The watt hour meter is __ instrument.
11. A transfer
12. A recording
13. An indicating
14. An integrating
15. The power transformer is usually rated in
16. kVAR
17. kW
18. kVA
19. kWh
    5 The relative permittivity has the following units
20. Wb/m
21. no units
22. m/F
23. F/m
    6 An example of a data storage device is
    (a) the logic gate
    (b) the flip-flop
    (c) the comparator
    (d) the register
    (e) both answers (b) and (d)
    7 Which of these sets of logic gates are designated as universal gates?
24. NOR, NAND
25. XNOR. OR, NOT
26. AND. XOR, NOR
27. NAND. NOR, NAND

8 A five variable Karnaugh map needs
A. 32 squares
B. 33 squares
C. 34 squares
D. 35 squares
9 Which diode is used in oscillator circuit?
A. tunnel diode
10 The output of XOR is high when
A. both the inputs are different
B. both the inputs are same
11 Output of ADC
A. binary

12. 1’s Complement of 1010
    A. 0101
    13) Passive antennas are antennas that have no amplification stages, like the CP Beam. An active
    antenna is a passive antenna that simply includes an onboard amplifier. Active antennas can be used
    for both receiving and transmitting applications, but they are most often seen as receiving antennas
    14) Superposition theorem applicable on
    a) linear networks
    b) non linear
    c) linear and bilateral
    d) linear and unilateral
    15) Capacitance of transmission line is a
    a) series component
    b) Shunt component
    16 The Ohm’s law is valid for _ circuit/s.
    A. linear
    B. non-linear and linear
    C. non-linear
    D. semiconductor
    17 Greatest Resistance offered by
    a) Galvanometer
    b) 1mA Ammeter
    c) 10V Rang Voltmeter
    18 Fuse used for
    a) Protection
    b) Current limiting
    c) Current Controlling
    d) all

19 Best connection for 3phase 4 wire system
a) Y-Y
b) Delta-Y
20 Weight of DC machine is __ than AC Machine
a) Greater
b) Smaller
21 Conditions for parallel operation of Transformers:
a) The line voltage ratio of two transformers must be equal
b) The per-unit impedance of each transformer should be equal and they should have the same
ratio (X/R) of equivalent leakage reactance to the equal resistance (X/R)
c) The transformers must have the same polarity.
d) The Transformers should have same phase sequence (Three-phase transformer)
e) The phase displacement between primary and secondary must be the same for all
transformers connected in parallel
f) all
22 Battery Capacity is measured in
a) Ah
b) Wh
c) J
23 Armature reaction decrease
a) Total flux
24 If the load on a synchronous motor increase, then its

1. Current drawn by motor increases and load angle also increases but decrease p.f.
   25 FM requires _ channel bandwidth over AM signal
2. much wider
   26 torque of induction motor is proportional to voltage by relation
3. V2
   27 Usually shape of tv antenna is
4. Rhombic
5. Yagi
6. Horn
   28 Best method to find transient and stability response
7. Root locus
   29 Skin effect increases when frequency increases
   30 Q factor increases bandwidth decreases
   31 Bundled conductor advantages
   Mechanical stability
   Current carrying capability increase
   Decreases reactance

32 Red, green, black, brown and silver resistance (BBROYGBVGW G(5)S(10))

1. 1500 +_ 10%
   33 Addition function in binary is
2. And
3. Or
   34 Graphite is used in nuclear reactor as
4. Moderator
5. Absorber
   Which of the following effects dominate in long transmission lines?
   (skin, Ferranti, Compton)
   Disruptive critical voltage for air is?
   (10kv/cm, 20kv/cm, 30kv/cm, 40kv/cm)
   At 11kv which of the following insulators used?
   (pin type, suspension, string, none of above)
   surge impedance of HV transmission line has a value of ?
   (20, 100, 300, 400, 500)
   The characteristic impedance of a transmission line is
   A. directly proportional to its length
   B. inversely proportional to its length
   C. independent of its length
   D. none of the above
   shielding angle for overhead transmission lines?
   (15, 30, 45, 60)
   If the normal system frequency is 50 Hz and if it is operating at 53 Hz, the equipment on the
   system most adversely affected is
   (a) Power transformer
   (b) Alternator
   (c) Turbine
   (d) all the above are equally
   Find the number of insulator discs required in string insulator, if operating voltage is 220 kV and
   maximum voltage of each disc is 11 kV?
6. 20
7. 10
8. 13
9. 21
   HVDC used for?
   (Long distances, short distances, medium)

Which of the following is an effect of non-uniform current distribution in a conductor?

1. Ferranti effect
2. Skin effect
3. Proximity effect
4. Skin effect or Proximity effect
   Thermal efficiency of a closed cycle gas turbine plant increases by……..
   A. Reheating
   B. Intercooling
   C. Regenerator
   D. All of the above
   Which of the following is more stable?
   cylindrical
   salient pole gen
   If the excitation of the synchronous generator fails, it acts as a/an
5. Synchronous generator
6. Synchronous motor
7. Induction motor
8. Induction generator
   Insulation resistance of a straight cable is:
9. Zero
10. Directly proportional to the length of cable
11. Inversely proportional to the length of cable
12. One
    Which tests are conducted to locate the fault location in the UG cables?
    a. Murray loop test
    b. Varley loop test
    c. Both (a) and (b)
    d. None of these
    When X/R=1, zero voltage regulation occur at p.f?
    (unity, leading 0.707, lagging 0.707, zero)
    real power transfer depends upon?
    (V diff, Angle diff, Vs, Vr, delta s)
    reactive power transfer depends upon?
    (V diff, angle diff, Vs, Vr, etc)
    power transfer angle practical value?
    (20, 30*, 45, 90)
    Which type is common for overhead lines?
    All Al, all Cu, ACSR
    A system which has some roots with real parts equal to zero, but none with positive real parts, is
13. Marginally stable
14. Relatively stable
15. Absolutely stable
16. Absolutely unstable

As frequency increases the flux inside the conductor
(a) Increases
(b) Decreases
(c) Constant
(d) Vanishes
Tunnel diode exhibits a special characteristic known as
A. positive resistance
B. positive reactance
C. negative resistance
D. negative reactance
What is the value of steady state error in closed loop control systems?
A. Zero
B. Unity
C. Infinity
D. Unpredictable
Reactors are used at various locations in the power system to
(i) increase short-circuit current
(ii) avoid short-circuit current
(iii) limit short-circuits current
(iv) none of above
Motor used for a domestic refrigerator is
A. Series motor
B. Shunt motor
C. Universal motor
D. Single phase induction motor
Generally which type of cooling method is recommended for transformers that are rated below 5
kVA:
Water cooling
Oil cooling
Forced water cooling
Air cooling
The fact as to how closely the instrument reading follows the measured variables is called the____.
a. Sensitivity
b. Fidelity
c. Precision
d. Accuracy
Which of the following is a desirable characteristic of an instrument?
A. High drift
B. High fidelity
C. High measuring lag
D. Poor reproducibility
Earth wire in overhead transmission lines:
Increases line inductance
Decreases line inductance
Increases line capacitance
Decreases line capacitance
The best suited motor to drive 3/4 H.P air compressor would be …………… motor.
(i) capacitor starts
(ii) single-phase series
(iii) shaded-pole
(iv) resistance split-phase
Sheaths are used in underground cables to

1. Provide proper insulation
2. Provide mechanical strength
3. Protect the cable from moisture
4. None of the above
   Primary current in a current transformer is determined by
   A. The load on the system
   B. The load on its own secondary
   C. The load on its own primary
   D. All of these
   The current in the electrical system is analogous to
   a. the temperature in the heat transfer system
   b. the heat flow in the heat transfer system
   c. the thermal conductance in the heat transfer system
   d. the thermal resistance in the heat transfer system
   As load factor of power plant increases, the electric power generation cost per kWh:
5. Increases
6. Decreases
7. Remains the same
8. Any of above
   The rating of the circuit breaker is usually determined on the basis of __ fault.
   A. Symmetrical
   B. Line to line
   C. Single line to ground
   D. Double line to ground
   If rated dc voltage is applied instead of ac to the primary of a transformer
   A. secondary of transformer will burn.
   B. primary of transformer will burn.
   C. secondary voltage will be excessively high.
   D. there will be no secondary voltage.
   The terminal voltage of dc shunt generator drops on load because of
   a) Armature reaction
   b) Armature resistance
   c) Weakening of the field due to armature reaction
   d) All of these
9. If the load on an over-compounded dc generator is reduced, the terminal voltage
   a) Increases
   b) Decreases
   c) Remains unchanged
   d) May increase or decrease
   Copper losses of an alternator can be measured by employing:
   Auto-transformer
   DC Motor
   Induction Generator
   Hydro-turbine
   The starting torque of a three-phase induction motor can be increased by
   A. Increasing slip
   B. Increasing current
   C. Both (A) and (B)
   D. None of the above
   The starting torque of a 3-phase induction motor can be increased:
10. by increasing the rotor resistance
11. by increasing the stator resistance
12. by increasing the air-gap between the stator and the rotor
13. none of these

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“The information presented in this blog post has been compiled from various engineering professionals’ accounts on social media platforms. It is intended for informational purposes only and does not necessarily represent official statements or policies of the individuals or organizations mentioned. Readers are encouraged to verify and cross-reference information independently.”