Chapter 1
Chapter 1
One. Which of the following parameters can be neglected for a short line?
b. Inductance c. Reactance d. Capacitance
Two. What does PEMC in EPIRA stands for?
a. Philippine Energy Market Corporation b. Private Energy Marketing Company c. Philippine Electricity Market Corporation d. Philippine Electrical Marketing Corporation
Three. What is the equivalent IEEE device number for an under-voltage relay?
a. Sixty-seven b. Fifty-two d. Fifty-one
Four. In the transformers a. High tension winding is used near the core b. High tension winding is used away from the core c. Low tension winding is used near the core d. Low tension winding is used away from the core
Five. The study of illumination involves a. Design of lighting system b. Study of lighting and wiring system c. Calculation of wiring sizes for various lighting fixtures d. Study of photometry and its application
Six. In television system, channels two and thirteen are classified as a. VHF
b. UHF
c. SHF
d. EHF
Seven. In a transmission line of negligible resistance, the surge impedance will be a. Square root of L C
b. Square root of L over C
c. Square root of one over L C
d. Square root of C over L
Eight. What is the IEEE device function number fifty?
a. AC time overcurrent relay b. Instantaneous overcurrent relay c. AC circuit breaker d. Differential protective relay
Nine. What determines the direction of force in a conductor?
a. Lenz law b. Faraday's law six. Left hand rule d. Right hand rule
Ten. A two terminal pair of network of a transmission line can be represented by b. T network C. Either A or B
d. Tree network
Eleven. PDC in EPIRA means a. Philippine Distribution
Commission b. Philippine Distribution Code c. Philippine Distribution
Corporation d. Philippine Distribution Company
Twelve. It is difficult to magnetize steel because of its a. High density b. High retentivity c. Low permeability d. High permeability
Thirteen. A distributor is designed from the point of view of a. Voltage drop b. Current carrying capacity c. Voltage drop and current carrying capacity d. Load capacity
Fourteen. Based on the Philippine Distribution Code, all users of the distribution system must maintain a certain power factor at the connection point in order to maintain power quality in the system. What power factor should be maintained at the connection point?
a. Not less than sixty-five percent b. Not less than seventy percent c. Not less than eighty-five percent d. Not less than seventy-five percent
Fifteen. For constant transmission Efficiency, voltage is increased n times, the size of the conductor would be a. Reduced to one over n times of the original b. Reduced to one over n squared times of the original c. Increased to n squared times of the original d. Increased to n times of the original
Sixteen. If the torque angle continuously increases, system will become a. Stable b. Unstable c. Oscillatory stable d. Asymptotic stable
Seventeen. Which of the following is not considered in the selection of surge arrester?
a. Voltage rating b. Current rating c. Class of arrester d. Insulation level
Eighteen. What governs the minimum safety requirement in the Philippines for distribution and grid?
a. Philippine Electrical Safety Code b. Philippine Electrical Code c. Philippine Electrical Grid Code d. Philippine Electrical Distribution Code
Nineteen. Copper loss of a transformer are determined by means of a test a. Open-circuit b. Polarity b. Polarity c. Short-circuit d. Inductive-circuit
Twenty. The effective resistance of conductor is increased by a. Skin effect b. Proximity effect c. Corona effect d. Both a and b
Twenty-one. What is the purpose of the reactor in short circuit a. To open the line in short circuit b. To decrease the circuit resistance c. To lessen the current in short circuit d. To increase the current in short circuit
Twenty-two. What is the maximum plug and cord rating of a thirty amp branch circuit a. Twenty-four amps b. Thirty amps c. Twenty-six amps d. Twenty-eight amps
Twenty-three. To adjust the power of the alternator, adjust the a. Power factor b. Governor c. Field current d. Frequency
Twenty-four. The power transmission capacity of the transmission is a. Inversely proportional to the voltage b. Directly proportional to the voltage c. Proportional to the square of the voltage d. Proportional to the cube of the voltage
Twenty-five. When a power plant is not able to meet the demand of consumers it will resort to a. Load shedding b. Efficiency plant operation c. Power factor improvement at the generators d. Penalizing high load consumers by increasing the charges of electricity
Twenty-six. In a diode modulator, what supplied the negative halfwave?
a. Inductor b. Capacitor c. Resistor d. Tuned Circuit
Twenty-seven. Which of the following plants will take least time in starting from cold condition to full load operation?
a. Gas turbine b. Steam power plant c. Nuclear power plant d. Hydroelectric power plant
Twenty-eight. Alternators installed in a hydro power station, are of a. Low speed b. High speed c. Medium speed d. Very high speed
Twenty-nine. What size of branch circuit is required for a window air conditioner with a nameplate rating of eight amps if the circuit also supplies other outlets?
a. Seventeen amps b. Twenty-five amps c. Twenty amps d. Fifteen amps
Thirty. Present day capacitors which have high capacitance in small size use a dielectric of a. Paper b. Rubber c. Ceramic d. Mylar
Thirty-one. The under voltage relays are usually used for what protection of the electrical equipment?
a. Feeder protection b. Motor protection c. Transformer protection d. Bus-bar protection
Thirty-two. Conservator of a transformer consists of a. An air-tight metal drum fixed at the top of the tank b. Drum placed at the bottom of the tank c. Overload protection d. None of these
Thirty-three. Which of the following is not included in the Technical Performance Standards for Distribution and Supply set by the Philippine Distribution Code?
a. Power Quality b. Reliability c. Collection Efficiency d. System Efficiency
Thirty-four. What kind of device is a diode?
a. Bilateral b. Linear c. Unipolar d. Nonlinear
Thirty-five. Which of the following insulators will be selected for high voltage application?
a. Strain type b. Disc type c. Suspension type d. Pin type
Thirty-six. In a shunt generator, the voltage builds up till constrained by a. Speed limitation b. Armature heating c. Saturation of iron d. Insulation restrictions
Thirty-seven. For proper parallel operation, AC polyphaser alternators must have the same a. Speed b. kVA rating c. voltage rating d. excitation
Thirty-eight. What device is used to measure the temperature of a motor winding while the motor is in operation?
a. Seismic probe b. Resistance temperature detector c. Thermocouples d. Proximity probe
Thirty-nine. The type of AC distribution system commonly used to supply both light and power is the a. Open delta system b. Three phase delta system c. Three phase wye system with neutral wire d. Three phase wye system without neutral wire
Forty. The current flowing in L and C at parallel resonance are a. Zero b. Equal c. Infinite d. Difference
Forty-one. The series field of a short-shunt compound de generator is excited by current a. Shunt b. Armature c. Load d. External
Forty-two. Which of the following type of fault used only the equivalent positive sequence impedance of the circuit in the short-circuit calculation?
a. Line to line b. Line to ground c. Double line to ground d. Three-phase fault
Forty-three. Which of the following methods of the generating electric power from the sea water is more advantageous a. Water power b. Ocean power c. Tidal power d. None of these
Forty-four. Base load plants are designed to supply power at a. Low capital cost and low operating cost b. High capital cost and low operating cost c. Low capital cost and low operating cost d. High capital cost and high operating cost
Forty-five. Peak load plants are designed to supply power at a. Low capital cost and low operating cost b. High capital cost and low operating cost c. Low capital cost and low operating cost d. High capital cost and high operating cost
Forty-six. When installing two grounding electrodes, the minimum distance between them is a. One thousand eight hundred millimeters b. Two thousand millimeters c. One thousand five hundred millimeters d. Two thousand four hundred millimeters
Forty-seven. Cellular phones operate in the frequency range of b. Very high frequency d. Super high frequency
Forty-eight. The reciprocal of permeability is a. Conductivity b. Susceptibility c. Reluctivity d. Permittivity
Forty-nine. For which of the following sinusoids, the rms value and mean value is the same?
a. Sine wave b. Triangular wave c. Square wave d. Half wave rectified
Fifty. If the effect of the earth is taken into account, then the capacitance of line to ground a. Decreases b. Increases c. Remains unchanged d. Becomes infinite
Fifty-one. The maximum efficiency of a half-wave rectifier is
Forty point six percent b. Eighty point six percent c. Fifty percent d. Twenty point three percent
Fifty-two. One thousand thirteen ergs per second is equal to how many kilowatts?
One thousand b. Two hundred fifty c. One hundred d. Ten
Fifty-three. Ideal transformer assumption do not include a. No leakage flux b. No saturation of force c. Zero resistance of the winding d. Zero reactance of the winding
Fifty-four. One kilowatt-hour is equal to British thermal units a. Three hundred sixty b. Three thousand four hundred thirteen c. Three thousand six hundred d. One thousand
Fifty-five. Varmeter when paired with other devices measures power factor?
a. Diversity b. Power c. Load d. Demand
Fifty-six. Heating effect of current has an undesirable side effect in a. Electric oven b. Immersion heater c. Electric iron d. Vacuum cleaner
Fifty-seven. When the sole purpose of an alternating current is to produce heat, the selection of conductor is based on value of the current.
a. Average c. Root mean square d. Peak
Fifty-eight. What is the primary advantage of FM over AM?
a. FM has a greater bandwidth than AM
b. Noise immunity c. More complex d. Greater capture effect
Fifty-nine. Which of the following is not included in the evaluation of Technical Performance of a Distribution System according to Philippine Distribution Code?
a. Power Quality b. Reliability c. Collecting Efficiency d. System Efficiency
Sixty. The phase angle for a series RC circuit may be computed as the angle between the and phasors.
a. Resistance, impedance b. Resistance, reactance c. Resistance, capacitance d. Impedance, reactance
Sixty-one. Which is not a characteristic of an ideal transformer?
a. Finite permeability b. Infinite permeability c. No losses d. No leakage flux
Sixty-two. In a synchronous motor, the magnitude of stator back emf depends on a. Load on the motor b. Direct current excitation only c. Both the speed and rotor flux d. None of these
Sixty-three. It is defined as the total number of sustained Customer power interruption within a given period divided by the total number of Customers served within the same period.
a. System average interruption frequency index b. System average interruption Duration index c. Customer average interruption frequency index d. Customer average interruption Duration index a. Resistance of a conductor which has a length of one meter and cross-section of one square meter at twenty degrees Celsius b. Resistance of any conductor at twenty-five degrees Celsius c. Resistance of any conductor at twenty degrees Celsius d. Resistance of a conductor which has a length of one meter and cross-section of one square centimeter at twenty degrees Celsius
Sixty-five. If an electrical network having one or more than one voltage source is transformed into equivalent electrical network with a single current source, which is the short circuit current of previous circuit, with parallel internal resistance of the network with all current source replaced by their internal resistance; the above illustration is called a. Thevenin's theorem b. Norton's theorem c. Reciprocity theorem d. Superposition theorem
Sixty-six. The impedance triangle is similar to the triangle with the resistance phasor in place of the a. Current, resistor current b. Current, resistor voltage c. Voltage, impedance d. Voltage, resistor voltage
Sixty-seven. A type of electronics communication in which only one party transmits at a time.
a. Full duplex b. Half duplex c. Bicom d. Simplex
Sixty-eight. Which is the most reliable power plant?
a. Steam b. Hydro c. Wind d. Tidal
Sixty-nine. Which of the following type of fault used only the equivalent positive and negative sequence impedance of the circuit in the short-circuit calculation?
a. Double line to ground b. Line to line c. Three-phase d. Line to ground
Seventy. Which is not a source of power?
a. Thermocouple b. Fuel coil c. Photovoltaic cell d. Solar cell
Seventy-one. When the frequency of a synchronous motor increases, what happens to its speed?
b. Increases c. Remains the same d. None of these
Seventy-two. What instrument measures the insulation of a power line?
a. Growler b. Ohmmeter c. Galvanometer d. Megger
Seventy-three. When electronics build up pressure at one point, it is called a. Ganging b. Current flow c. Impedance d. Pressure filing
Seventy-four. The curve representing Ohm's law is a. A parabola b. Linear c. A sine function d. A hyperbola
Seventy-five. Which of the following principle will the operation of fiber-optic cable is based?
a. Dispersion b. Refraction c. Reflection d. Absorption
Seventy-six. The overcurrent protective device is caused to operate by a. Voltage surge b. Current flow c. Voltage drop d. Impedance
Seventy-seven. What is the maximum number of bends permitted in rigid conduits between outlets?
a. Four quarter bends b. Six quarter bends c. Two quarter bends d. Three quarter bends
Seventy-eight. Which of these is not a factor in the selection of fuse rating for protection of branch circuit?
a. Branch full-load current b. System impedance c. Branch fault-current d. System voltage
Seventy-nine. The condition in Ohm's Law is that a. Ratio V over I should be constant b. Current should be proportional to voltage c. The temperature should remain constant d. The temperature should vary
Eighty. Which of the following shall be included in the calculation of reliability standard indices of the distributor asset by the Philippine Distribution Code?
a. Outages that occur on the secondary lines of the distribution system b. Planned outages where the customers have been notified at least three days prior to the loss of power c. Outages that occur on the primary lines of the distribution system
Eighty-one. For two alternators operating in parallel, if the load shared by one of them is to be increased, as field excitation is a. To be strengthened keeping input torque the same b. To be weakened keeping input torque should be increased c. To be kept constant but input torque should be increased d. To be kept constant but input torque should be decreased
Eighty-two. Which of the following that the voltage regulation is one of the important factors considered in the electrical power design?
a. Generator b. Transmission line c. Feeder d. Transformer
Eighty-three. Open circuit test on transformer is conducted to determine a. Hysteresis loss b. Copper loss c. Core loss d. Eddy current loss
Eighty-four. Which of the following power plant is a conventional source of energy?
a. Solar energy b. Geothermal energy c. Coal energy d. Wind energy
Eighty-five. Which of the following is a primary disadvantage of FM over AM?
a. Lower efficiency b. Noise susceptibility c. Higher cost and complexity d. Excessive use of spectrum space
Eighty-six. R A seven eight three two concerns on a. Pilferage of electricity, theft of transmission materials and capping of system loss b. Pilferage of electricity, theft of transmission materials and rationalizing of system loss c. Pilferage of electricity energy d. Pilferage of electricity and electrical materials
Eighty-seven. If the current in the armature of a direct current series motor is reduced by fifty percent the torque of the motor will be reduced by what percentage of the previous value?
a. Twenty-five b. Fifty c. Thirty-three d. Seventy-five
Eighty-eight. A coil that opposes any change in current flow is called a(n)
a. Transducer b. Capacitor c. Oscillator d. Inductor
Eighty-nine. A substance that changes its electrical resistance when illumination by light is called?
a. Photovoltaic b. Photoconductive c. Photoelectric d. None of these
Ninety. Which of the following define the meaning of the load factor?
a. The ratio of average load to installed capacity b. The ratio of maximum load to average load c. The ratio of average load to maximum load d. The ratio connected load to maximum load
Ninety-one. The transient current in a loss free L C circuit when excited from an alternating current source is a/an sine wave.
a. Over-damped b. Under-damped c. Critically damped d. Undamped
Ninety-two. The calculation of the reliability indices of the grid owners as set by Philippines grid code shall include outages that occur a. Due to generation deficit b. On the secondary line system c. On the transmission line d. On the primary lines of the distribution line
Ninety-three. The size of conductor on E H V lines is obtained based on a. Currently density b. Corona c. Voltage drop d. Voltage density
Ninety-four. When peace and order problem exist, National Grid Corporation of the Philippines issues a. Security alert b. Imminent danger alert c. Decrease in length d. None of this
Ninety-five. Conduction electrons move to the right in a certain wire. This indicated that:
a. The current density and electric field both point right b. The current density point right and electric field point left c. The current density point left and electric field point right d. The current density and electric field both point left
Ninety-six. What does P E M C in E P I R A stands for a. Philippine energy market corporation b. Philippine electricity market corporation c. Private energy market company d. Philippine electrical marketing corporation
Ninety-seven. The growth rate of energy consumption in our country is six point nine percent. In how many years will the energy be quadrupled?
a. Thirty b. Twenty c. Fifteen d. Twenty-five
Ninety-eight. For power transformers the conservator tank is intended to minimize a. Breathing b. Oil sludging c. Heating d. Internal pressure
Ninety-nine. A pure semiconductor without doping is called b. Half of the original value c. Double the original value d. One-fourth of the original value
One hundred thirty-eight. The highest speed attained by a direct current shunt motor is a. Equal to infinity at rated flux b. Higher than no load speed at rated flux c. Equal to no load speed at rated flux d. Lower than no load speed at rated flux
One hundred thirty-nine. Chemicals with lower flash points presents a greater a. Personal hazard b. Flammability hazard c. Explosion hazard d. Skin hazard
One hundred forty. The product of root mean square values of current and voltage is called a. Real power b. Apparent power c. Reactive power d. Polar curves
One hundred forty-one. Ohm's law is not applicable to a. Vacuum tubes b. Carbon resistors c. High voltage circuits d. Circuits with low current densities
One hundred forty-two. Which medium has the highest value of dielectric strength?
a. Glass b. Porcelain c. Mica d. Quartz
One hundred forty-three. Which of the following buses constitute the maximum number in a power system?
a. Slack bus b. P Q bus c. P V bus d. All of these
One hundred forty-four. In order to transfer the load from one alternator to another alternator, when they are operating in parallel a. Field current is increased b. Field current is decreased c. Speed is decreased d. Prime mover power input is increased
One hundred forty-five. K C L works on the principle of which of the following a. Law of conservation of charge b. Law of conservation of energy c. Both d. None of these
One hundred forty-six. The law that induces emf and current always opposes the cause producing them was discovered by a. Faraday b. Maxwell c. Lenz d. Ohm
One hundred forty-seven. Series capacitor are used to a. Improve the line voltage b. Compensate for line inductive reactance c. Compensate for line capacitive reactance d. None of these
One hundred forty-eight. Which of the following distribution system gives the greater reliability?
a. Radial system b. Ring system c. Direct current three wire system d. Open loop system
One hundred forty-nine. The transformer oil used in transformers provide a. Cooling and lubrication b. Insulation and lubrication c. Insulation and cooling d. Insulation, cooling and lubrication
One hundred fifty. If the capacitance of the transmission line is increased, the transmitted power will a. Remain same b. Increase c. Decrease d. Tend to zero at the receiving end
One hundred fifty-one. Which increases the resistance of a conductor a. Increase in size b. Increase in length c. Decrease in length d. None of these
One hundred fifty-two. A type of electronics communication in which only one party transmits at a time a. Full duplex b. Half duplex c. Bicom d. Simplex
One hundred fifty-three. What device is used to measure the temperature of a motor winding while the motor is in operation?
a. Seismic probe b. Resistance temperature detector c. Thermocouples d. Proximity probe
One hundred fifty-four. The amount of frequency deviation from the carrier center of frequency in an FM transmitter is proportional to the a. Shape b. Amplitude c. Frequency d. Phase
One hundred fifty-five. In the differential current protection system the current transformer secondaries of wye-delta power transformers will be in a. Delta-delta b. Delta-wye c. Wye-wye d. Wye-delta
One hundred fifty-six. When a current carrying conductor is brought into a magnetic field, the force that moves the conductor depends upon the a. The direction of the conductor b. The value of the current c. The weight of the conductor d. None of these
One hundred fifty-seven. Which of the following types of heating process is used for surface hardening of steel?
a. Induction b. Resistance c. Dielectric d. Infrared
One hundred fifty-eight. A test used to determine the equivalent resistance of an induction motor is a. Blocked rotor test b. No-load test c. Short circuit test d. Polarity test
One hundred fifty-nine. Power lost due to alternating magnetization and demagnetization of the core materials a. Copper loss b. Hysteresis loss c. Eddy current loss d. Rheostat loss
One hundred sixty. An act penalizing pilferage of electricity, theft of transmission lines and materials and rationalizing system loss by phasing out pilferage losses a. R A seven nine two zero b. R A seven eight three two c. R A nine one three six d. R A eight four nine five
One hundred sixty-one. The protection from negative sequence currents is provided for
One hundred sixty-two. What is the IEEE standard device number for under voltage relay?
One hundred sixty-three. Identify the passive element among the following
One hundred sixty-four. The term which allows any person or entity in the purchasing the energy from transmission, distribution which ever have low charge rate
One hundred sixty-five. The voltage regulation is an important factor in the design of
One hundred sixty-six. What characteristics of plates of the battery where ampere hour is rated?
One hundred sixty-seven. Calculation of reliability standards of grid owner set by Philippine Grid Code shall exclude outages that occur on the
One hundred sixty-eight. What is maximum output of
One hundred sixty-nine. What is the device used by computers to communicate to other computer through telephone line?
One hundred seventy. Buchholz relay cannot be installed on
One hundred seventy-one. Which of the following given below is the eddy current loss not proportional to?
One hundred seventy-two.
Kirchhoff's voltage law?
One hundred seventy-three. The circuit breaker rating relevant to transient stability is
One hundred seventy-four.
Define Kirchoff's voltage law d. Algebraic sum of currents Symmetrical component method of analysis is more useful when
One hundred seventy-five.
One hundred seventy-six. The nodal method of the circuit analysis is based on
One hundred seventy-seven. Which of the following relays gives a fore-warning of a possible major fault
One hundred seventy-eight. Handling of the telephone receiver may become dangerous due to from a power line
One hundred seventy-nine. The two windings of a transformer is
One hundred eighty. The machine reactance's used for computation of short circuit current ratings of a circuit breaker are
One hundred eighty-one.
One hundred eighty-two. The percentage regulation of an overhead transmission line can be zero when the load power factor is
One hundred eighty-three Fermi energy is the amount of energy which
One hundred eighty-four. What is the main advantage of FM over AM?
One hundred eighty-five. Bundled conductors are used in EHV lines primarily for d. Reduce internal inductance AC system has the following
One hundred eighty-six.
disadvantages over DC system
One hundred eighty-seven. Resistance of the conductor increases when
One hundred eighty-eight. The surge impedance of a telephone line is
One hundred eighty-nine. Two or three sheds or petticoats are provided in pin-type insulators in order to increase
One hundred ninety. The internal voltages of a threephase synchronous generator correspond to
One hundred ninety-one.
One hundred ninety-two. Expanded ACSR conductors are
One hundred ninety-three.
PRC Modernization Act of two thousand
One hundred ninety-four.
is also known as
One hundred ninety-five. Voltage regulation of a short transmission line is
One hundred ninety-six. Most commonly used supports for high tension lines is
One hundred ninety-seven. PEC defines as Recognizable as suitable for the specific purpose function, use, environment, application and so forth
One hundred ninety-eight. A motor which can conveniently be operated at lagging as well as leading power factors is the
One hundred ninety-nine.
A terminal where more than two branches met is called
Two hundred. Out of the following methods of heating the one which is independent of supply frequency is
Two hundred one. Transmission voltages in the range two hundred thirty kilovolts to seven hundred sixty-five kilovolts are known as
Two hundred two. The emf induced in the primary of a transformer
Two hundred three. Shunt compensation for long EHV lines is primarily resorted to
Two hundred four.
a. Construction rule
Two hundred five.
Two hundred six.
Two hundred seven. Which method is used for fast
Two hundred eight. If a transformer primary is energized from a square wave voltage source, its output voltage will be
Two hundred nine. The temperature of resistance furnaces can be controlled by changing the:
Two hundred ten. In a suspension insulator, the mechanical stresses on the conductor are
Two hundred eleven. The amount of frequency deviation from the carrier center of frequency for FM transmitter is proportional to what characteristic of the modulating signal?
Two hundred twelve. Reduction in the capacitance of a capacitor start motor, results in reduced