25550557

Republic of the Philippines
Professional Regulation Commission
Board of Electrical Engineering
Electrical Engineering Board Examination 8:00 am – 12:00 noon
PROFESSIONAL ELECTRICAL ENGINEERING SUBJECTS SET A
ELECTRICAL2/Page 1
E2
INSTRUCTION: Select the correct answer for each of the following questions. Mark
only one answer for each item by shading the box corresponding to the letter of
your choice on the answer sheet provided.
STRICTLY NO ERASURES ALLOWED. Use pencil no. 1 only.
NOTE: Whenever you come across a caret (^) sign, it means exponentiation.
Ex. x^2 means x2; (x+y)^(x-z) means
(x+y) raised to the (x-z). Pi=3.1416
MULTIPLE CHOICE
1. Find the impedance which requires 1549 VAR AT 230 V rms and 10 A rms.
A. 17.40 - j15 ohms C. 17.09 - j15.39 ohms
B. 16.82 – j15.69 ohms D. 17.62 – j14.78 ohms
2. For a series RLC circuit with elements R = 50 Ω, L = 8 mH and C = 2.22 μF.
What is the equivalent impedance of the circuit if its frequency is 796 Hz?
A. 50 – j50 ohms C. 50 + j130 ohms
B. 50 + j50 ohms D. 50 – j130 ohms
3. Find the current that will follow in a series circuit containing a 5 kohm
resistor, a 470 picoF capacitor, a 150- mH inductor, and a 0.001 microfarad if
the exciting voltage is 65 volts at 25kHz.
A. 6.32 +j8.46mA C. 8.46+j6.22mA
B. 6.22-8.46mA D. 8.46-j6.22mA
4. Two impedances, Z1=0.8+j5.6 and zZ2=8-j16 and the single phrase motor are
connected in parallel across 200 Vrms. 60Hz supply. The motor draws 5 kVA at
80% power factor lagging. Find the complex power of impedance Z2?
A. -1-j2kVA C. 2+ j1kVA
B. 1-j2kVA D. -2-j1kVA
5. What are the two elements in a series circuit connection having a current and
voltage i= 13.42 sin (500t-53.4degrees) A and v= 150sin (500t+10degrees) V?
A. R= 8.8 ohms and L=35mH C. R= 6.3 ohms and L=25mH
B. R= 7.5 ohms and L=30mH D. R= 5.0 ohms and L=20mH
6. The impedance Z3 in series to the two impedances Z1= 10+ j10 ohms and Z2= 20-
j30 ohms that are connected in parallel. What is the value of the impedance Z3
in ohms that will produce resonant circuit?
A. –j13.1 C. j13.1
B. j5.4 D. –j5.4
7. One hundred picofarad capacitor is connected in series with a coil having
inductance of 100μH and a resistance of 100 ohm. At what frequency will this
network have at unity pf.
A. 1.4 MHz C. 1.8 MHz
B. 1.2 MHz D. 1.6 MHz
8. A 125-F capacitor that has a n initial voltage of 25-V is charge with a
current that varies with time according to the equation i = t (t2+6.83)1/2.
Find the voltage across the capacitor at 1 s.
A. 26 V C. 25 V
B. 20 V D. 20.2 V
9. Find the current through a 0.1 microfarad capacitor at t = 0, if the voltage
across it is -2 e-10^7t V.

Republic of the Philippines
Professional Regulation Commission
Board of Electrical Engineering
Electrical Engineering Board Examination 8:00 am – 12:00 noon
PROFESSIONAL ELECTRICAL ENGINEERING SUBJECTS SET A
ELECTRICAL2/Page 2
E2
A. 200 mA C. 20 A
B. 20 mA D. 2 A
10. A balanced three-phase wye-connected load of 150 kW takes a leading current
of 100 A, when the line is 2400 V, 60 Hz. What is the capacitance per phase?
A. 21 Mf C. 205 mF
B. 21 μF D. 205 μF
11. A balanced delta connected load of 4 – j3 ohms per phase is fed by a 380 V,
three-phase system. Find the reactive power.
A. 52 kVARS C. 69 kVARS
B. 29 kVARS D. 87 kVARS
12. The phase currents in a wye-connected unbalanced load are la – 44 – j33, lb =
-32 – j24, and lc = -40 + j25 A. What is the positive sequence current for
phase A?
A. -28 – j21 A C. 28 – j31 A
B. 40.8 + j8.9 A D. 40.8 – j8.9 A
13. A 240 V (line to neutral) three-phase source is connected to three 10 ohm
resistance loads with both source and load in the Y-configuration. Determine
the current in each phase
A. 22 A C. 24 A
B. 20 A D. 28A
14. A balanced three-phase wye connected source has using positive phase
sequence. Van = 220 V rms with 30 degrees angle. Determine Vbc.
A. 190.5 + j330 V C. -190.5 – j330 V
B. 190.5 – j330 V D. – j381 V
15. In a balanced three-phase system, the wye-connected impedances connected are
10 ohms with 30 degrees angle. If Vbc is equal to 416 V with 240 degrees
angle, determine Icn. Assume the phase sequence is abc.
A. 12 + j20.8 A C. 12 – j20.8 A
B. 20.8 – j12 A D. 20.8 + j12 A
16. Given the following phase currents, Ia = 3.5 + j3.5, Ib = 0 – j3 and Ic = -2.6
+ j1.6. determine the negative sequence current for phase A.
A. 0.333 + j0.678 C. 0.424 + j0.571
B. -0.333 – j0.678 D. -0.333 + j0.678
17. Given the following sets of symmetrical components currents, determine the
phase B current.
Current Magnitude Angle, degrees
Ia0 1.0 75
La1 1.0 15
La2 1.0 -45
A. 0.259 + j0.966 C. 1.932 + j0.518
B. 0.516 + j1.931 D. 1.414 + j1.414
18. A transformer having a 360 turn primary winding takes 150 W in power and 1.4
A in current at an input voltage of 230 volts. Determine the no-load power
factor.
A. 0.606 C. 0.466
B. 0.866 D. 0.523
19. A transformer when it is operated as a conventional two winding transformer

Republic of the Philippines
Professional Regulation Commission
Board of Electrical Engineering
Electrical Engineering Board Examination 8:00 am – 12:00 noon
PROFESSIONAL ELECTRICAL ENGINEERING SUBJECTS SET A
ELECTRICAL2/Page 3
E2
is rated 10 MVA, 12/1.2 kV, 60 Hz. Under these conditions, its series
resistance and reactance are given as 2% and 7% pu respectively. This
transformer is to be used as 13.2/12 kV step-down autotransformer in a power
distribution system. What is the transformer’s series impedance in pu in the
autotransformer connection?
A. 0.0017 + j0.0058 C. 0.0020 + j0.0070
B. 0.0022 + j0.00778 D. 0.0018 + j0.0064
20. A transformers rated 500 kVA, 4800/480 V, 60 Hz when operated as a
conventional two winding transformer is to be used as a 5.28/4.8 kV step down
autotransformer in power distribution system. In the autotransformer
connection, when is the transformer’s rating when used in this manner?
A. 5MVA C. 5.5 MVA
B. 6MVA D. 6.5 MVA
21. The open circuit and short circuit tests were performed on the primary side
of the 25 kVA, 7620/240, 60 Hz transformer and the following data were
obtained, open circuit test; Eoc = 7620 V, Ioc = 0.30 A and Poc = 500 W. Short
circuit test Esc = 450 V, Isc = 3.5 A and Psc = 220 W. Determine the shunt and
series impedances refer to the primary of the transformer.
A. 116 + j26 k & 17.97 + j130  C. 112 + j22 k & 15.95 + j128 
B. 124 + j14 k & 21.85 + j134  D. 120 + j10 k & 19.95 + j132 
22. An induction motor is rated 240 V, 150 A and 0.707 power factor. What is the
size of the capacitor in kVAR which must be place in parallel with the circuit
to improve the power factor to 95% lagging?
A. 17.1 C. 41.9
B. 24.3 D. 26.9
23. A transmission line cable consists of 26 strands of identical copper
conductor, each 1.255 mm in diameter. The length of the cable is 10 km but
because of the twist of the strands, the actual length of each conductor is
increased by 5%. If the resistivity of the copper is 1.72 x 10-8 ohm-meter,
what is the resistance of the cable in ohms?
A. 1.08 C. 1.13
B. 5.39 D. 5.66
24. A single-phase transmission line 90 km is made up of hard drawn copper 500
mils in diameter. If the resistivity of the hard drawn copper at 20°C is 1.72
x 10-8 ohm-meter. Determine the loop resistance at 20°C.
A. 0.1394 ohm/km C. 0.546 ohm/km
B. 1.348 ohm/km D. 0,434 ohm/km
25. A three-phase transposed distribution line is designed with equilateral of 12
ft. it is decided to build the line with horizontal spacing D31=2D12=2D23.
What should be the spacing between adjacent conductors in order to obtain the
same inductance as the original design?
A. 9. 5246 ft C. 9.5066 ft
B. 9,6437 ft D. 9.6198 ft
26. A 69 kV three phase transposed line is composed of one ACSR 336,400 cmil,
36/7 Linnet conductor per phase with a horizontal configuration of D12=5 ft,
D23= 5 ft and D23=10 ft. The conductors have diameter of 0.721 inch,
resistance of 0.306 ohm per mile and gmr of 0.0244 ft. What is the reactance
for 12 miles line.
A. 6 ohms C. 4 ohms
B. 2 ohms D. 8 ohms

Republic of the Philippines
Professional Regulation Commission
Board of Electrical Engineering
Electrical Engineering Board Examination 8:00 am – 12:00 noon
PROFESSIONAL ELECTRICAL ENGINEERING SUBJECTS SET A
ELECTRICAL2/Page 4
E2
27. A single circuit, transposed overhead transmission line is composed of two-
conductors per phase. The diameter of each conductor is 5 cm. the distance
between the center of the bundle is 5 m. What is the inductance per km per
phase of the line.
A. 0.4412 mH C. 0.9323 mH
B. 0.9136 mH D. 0.8825 mH
28. A three-phase circuit, 60 Hz, 230 kV transposed transmission line is composed
of two 1272 MCM, 54/19 conductors per phase with horizontal configuration. The
bundle spacing is 50 cm while phase spacing between the centers of the bundle
is 10 m. If the GMR of the ACSR conductors is 0.466 ft, find the inductive
reactance in ohm/km/phase of the transmission line?
A. 0.3775 C. 0.3628
B. 0.3398 D. 0.3964
29. A 115-kV three-phase transposed transmission line is composed of two ACSR
336,400 cmil, 36/7 Oricle conductors per phase with horizontal
configuration:D12=7 ft; D23= 7 ft and D13= 14 ft. The line spacing as measured
from the center of the bundled conductors is 6 inches. The conductors have a
diameter of 0.741 inch a GMR of 0.02265 ft. Find the capacitance per phase for
20 km of the line in microfarads.
A. 0.2889 C. 0.2300
B. 0.2609 D. 0.2719
30. A 75 kVA, 13.2 kV/240V delta-wye distribution transformer has a resistance of
1% pu and reactance of 8% pu. Wht is the transformer’s phase impedance
referred to the high voltage side?
A. 69.70 + j557.57ohms C. 71.09 + j558.72 ohms
B. 69.95 + j543.63 ohms D. 70.58 + j564.54 ohms
31. The per phase parameters for a 60 Hz, 200 km long transmission line are
R=2.07 Ω and L=310.8 mH and C=1.4774 μF. The transmission line supplies a 100
MW, wye connected load at 215 kV (line to line) and 0.9 power factor lagging.
Using nominal π model, determine the sending end voltage line to line.
A. 229 kV C. 236 kV
B. 243 kV D. 233 kV
32. A generator of 50 MVA, 4 kV, X”d=25% and a transformer of 50 MVA, 4kV
delta/115 kV wye-grounded operating on a 3.8 kV tap where Xt”=10% to be
connected into a single equivalent reactance. What is the single equivalent
reactance on a 100 MVA, 110-kV base?
A. j0.7667 pu C. j0.8663 pu
B. j0.6039 pu D. j0.8241 pu
33. The effect of the dielectric is to
A. increase the capacitance C. decrease the capacitance
B. increase the working voltage D. reduce the working voltage
34. What will happen to an insulating medium if subjected to a voltage more than
its basic impulse insulation level? It will________.
A. change its molecular structure C. become magnetic
B. punctured D. melt
35. If the certain conductor has an area of 336,400 cmils, what is the radius of
this conductor in cm?
A. 0.663 C. 0.737
B. 0.8310 D. 0.921

Republic of the Philippines
Professional Regulation Commission
Board of Electrical Engineering
Electrical Engineering Board Examination 8:00 am – 12:00 noon
PROFESSIONAL ELECTRICAL ENGINEERING SUBJECTS SET A
ELECTRICAL2/Page 5
E2
36. A 110V dc motor draws current of 30A and is located 500ft from the power
source. What is the supply voltage if the diameter of the copper wire is 0.25
inch? Resistivity is 10.4 omhs-cmil per ft.
A. 119 V C. 121 V
B. 117 V D. 115 V
37. A series loop contains the following circuit elements in order a 8-volts
source, a 2k ohms resistor, a 3k ohm resistor, a 16-V source and a 7k ohm
resistor. What is the power absorbed by the 3k ohm resistor?
A. 12 mW C. 0.12 W
B. 1.2 mW D. 1.2 W
38. Three resistors 3, 4 and z ohms respectively are connected in parallel across
a constant current source of 10A. Find the value of z if the resistor draws 3
A current.
A. 6 ohms C. 4 ohms
B. 2 ohms D. 8 ohms
39. The voltage applied across the resistor was reduced by 50%. The power
consumed by resistor will reduced by?
A. 75 C. 25
B. 50 D. 100
40. A 6 V car radio draws a current of 6.5 A. What resistance in ohms must be
connected in series with it to operate it in a car with a 12 V battery?
A. 0.947 C. 0.923
B. 0.969 D. 0.981
41. Three resistors R1=9k ohm, R2=9k ohm and R3=9k ohm are connected in parallel
across a 12-V power supply whose internal resistance is 1k ohm. How much
current is drawn from the source?
A. 6mA C. 2.4 mA
B. 3mA D. 1.2 mA
42. A 20-ohm resistor is connected in parallel with a variable resistor R. The
parallel combination is the connected in series with a 4-ohm resistor and
connected across a 240V source. Determine the minimum value of R if the power
of r is equal to the power taken by the 4-ohm resistor.
A. 7.95 ohms C. 7.64 ohms
B. 8.40 ohms D. 6.87 ohms
43. Two batteries are connected in parallel to feed a 12-ohm load. Battery A has
open circuit emf of 6.3V and internal resistance of 1.5 ohms. Battery B has
open circuit emf of 6V and an internal resistance of 2.1 ohms. What is the
load current?
A. 0.48 A C. 0.44 A
B. 0.52 A D. 0.56 A
43. The resistance of a length of copper wire is 2.6 ohms at 20deg. C. The temp
coefficient of resistance on a 20deg. C for copper is 0.0393. What is its
resistance at 75deg. C?
A. 3.670 ohms C. 11.38 ohms
B. 3.162 ohms D. 4.378 ohms
44. A length of a copper telephone line has a resistance of 24 ohms at 20deg. C.
What is the resistance on a hot summer day when its temp. raised to 36deg. C?
A. 26.5 ohms C. 25.5 ohms
B. 24.5 ohms D. 27.5 ohms