Free Printable C7 rj

Worksheets

C7 rj

Total questions: 125

Worksheet time: 1hrs 3mins

Name

Class

Date

1. Moisture accumulating in electric motors and generator windings having a cold insulation

resistance greater than 50,000 ohms may be baked out with internal heat. This heat can be

developed by_

•short circuiting the armature and field windings

•short circuiting the field windings and passing current through the armature

•obtaining current from a DC source such as an electric welder and feeding it into the

armature while running the motor at full speed

•feeding current into the windings at low voltage

2. What precaution should be taken with a vessel's impressed current cathodic protection

system after a drydocking period during which the hull has been painted?

•Reference cell voltages should be maintained at half at the normal range for approximately

48 hours

•The unit should remain off for the specified amount of time so as not to disturb curing

•A slight (10-15 %) over current to the anodes should be allowed in order to speed drying

•Output currents should be carefully monitored to assure operation at nearly 100% capacity

for proper curing

3. The schematic symbol for an operational amplifier in an analogue circuit is a

•Square

•Trapezoid

•Triangle

•Circle

4. A three-phase squirrel-cage induction motor will run hot due to

•Reversed commutating poles

•Open stator coils

•High power factor

•Dirty or corroded slip rings

5. A capacitor can be tested using a megohmmeter or an ohmmeter, if the meter is connected

to a shorted capacitor, the meter pointer should_

•first swing quickly to zero, then gradually moved up the scale as the capacitor charges

•immediately swing to a high reading and then gradually decrease

•immediately deflect to and remain at zero

•immediately tswing to the maximum resistance value for the capacitor

7. A switchboard for an AC electrical system requires the use of which of the following

devices?

•Ohmmeter

•Current transformer governor

•Induction voltage regulator

•Frequency meter

8. When changing tubular fuses always use a

•Fuse puller

•Electrician s plier

•Rubber boots

•Screw driver

9. The greatest single cause of electrical failure is

•Overcurrent

•The breakdown of insulation

•High inductance

•Too frequent testing

10. What will you do if the generator is exposed to rain or any water?

•Run the system for 1 hour to test the performance.

•Use hygrometer to test the moisture.

•Check the coil if insulation is pilled up.

•Make a megger test

10.

11. A safety device in an electrical circuit consisting of metal strip that melts when the current

exceeds the safe level is called

•diode

•rheostat

•circuit breaker

•fuse

11.

12. An electric tachometer receives the engine speed signal from?

•stroboscopic sensing device

•small generator mounted on the engine

•vibrating reed meter generating a voltage proportionate to engine speed

•bimetallic sensing device

12.

13. A current at which a magnetic-type overload relay tends to trip maybe decreased by

raising the plunger further into the magnetic circuit of the relay. This action will

•Reduces magnetic pull on the plunger and requires more current to trip the relay

•Increases magnetic pull on the plunger and requires less current to trip the relay.

•Increases magnetic pull on the plunger and requires more current to trip the relay

•Reduces magnetic pull on the plunger and requires less current to trip the relay

13.

14. What does the variable resistance placed in the rotor circuit of a wound-rotor induction

motor provide?

•frequency control

•speed control

•voltage control

•use as a split-phase motor

14.

15. Periodic testing of circuit breaker is necessary to assure that a correct rated and properly

installed unit

•will continue to provide the original degree of protection

•does not exceed its interupting capacity

•be able to withstand at least 125 % of applied voltage

•can trip faster as it increases intalled unit

15.

16. Which of the following materials is recommended for finishing the slip rings after grinding

or turning?

•smooth file

•crocus cloth

•grade 00 sandpaper

•canvas wiper

16.

17. What kind of device that has two pieces of metal joined together so that when its junction

is heated, a voltage is produced?

•Load cell

•Proximity

•Thermocouple

•Strain gage

17.

18. When removing ball or roller bearings from the shaft of a motor, you should use a

•rawhide hammer

•wheel puller

•soft iron pry ba

•brass mallet

18.

19. What do do you call on a periodic testing by a shore side support technician using a special

camera which can detect potentially dangerous loose or corroded bus bar and controller

connections?

•corrosion electrolysis

•heat sensitive thermography

•electric vibroanalysis

•visual pyrotronics

19.

20. When the equivalent circuit diagram of double squirrel-cage induction motor is

constructed the two cages can be considered.

•in parallel with stator

•in parallel

•in series

•in series-parallel

20.

21. What motor is fitted with an instantaneous overload relay?

•Machine tool

•Fan

•Pump

•Winch

21.

22. If both the "high level and "low level''alarms come on for the same address of a centralized

control console, the most likely problem is alan

•low level

•extremely high level

•failed alarm

•sensor failure

22.

23. Which of the listed procedures should be carried out to prevent moisture damage to

electrical apparatus during extended periods of idleness?

•Place heat lamps in the motor housings.

•Strap silica gel around the commutator.

•Fill the motor housing with CO2 to inert the space.

•Cover the equipment with a canvas tarpaulin.

23.

24. A common type of protective covering used on electrical conductors is

•babbitt sheathing

•fibrous braid

•plain paper

•silver sheathing

24.

25. When a nickel-cadmium battery begins gassing while connected to the battery charging

circuit, you should

•do nothing as this is a normal condition when charging

•add distilled water to each cell to increase the specific gravity of the electrolyte

•increase the charging rate

•add potassium hydroxide to each cell to reduce the specific gravity of the electrolyte

25.

26. A molded-case breaker provides protection against short circuits by using ?

•holding coil

•electromagnet

•arc quencher

•shading coil

26.

27. What may happen to the components of a winch master control switch, if the cover gasket

becomes deteriorated?

•Rapid corrosion of switch components.

•Sparking at the winch motor brushes.

•Contamination of lube oil.

•Overheating of the winch motor.

27.

28. What should you use to determine if a stator coil is grounded?

•ground detection lamp

•ammeter

•megger

•magneto

28.

29. The charging of lead-acid storage batteries will always result in ?

•the danger of lead poisoning

•dangerous acid burns

•a dangerously explosive gas being liberated

•increased level of electrolye

29.

30. With both ends of a three conductor cable disconnected and arranged without the

conductors touching each other, an ohmmeter reading of 'zero' ohms between the ends of

one conductor would indicate

•the resistance is infinite

•a partial ground

•a short circuit

•continuity

30.

31. What is a device that changes an input signal of one type into an output signal of a differnt

type that is proportional to the original input?

•web framedSensor

•Transducer

•Transmitter

•Controller

31.

32. What gives the information about the speed of a motor in D. C. Generator,

•Potentiometer

•Voltmeter

•Watt hour meter

•Speedometer

32.

33. To check the three line fuses of three-phase system consisting of a three-phase motor, you

must

•place the starter in the Âostop' position

•place the leads across the ÂOhot' ends of the fuses

•place the leads across the bottom ends of the fuses

•make sure the motor is operating at full load to guard against a false reading

33.

34. periodic testing of circuit breakersis necessary to assure that a correct rated and properly

installed unit

•will continue to provide the original degree of protection

•be able to withstand at least 125 % of applied voltage

•does not exceed its interupting capacity

•can trip faster as it increases intalled unit

34.

35. How should controller contacts be routinely cleaned?

•dressing with crocus cloth

•wiping with a clean dry cloth

•blowing with compressed air

•filing with a bastard file

35.

36. Which of the following safest precautionary measure is to be done prior working on the

motor of the cargo winch?

•Put the boom at its rest before work start.

•Inform chief officer that winch cannot be used for cargo operation,

•Inform master that a cargo winch water needs repair.

•Switch off main switch and put sign do not switch on.

36.

37. Four lamps are connected in parallel in a single circuit. If one of the lamp burns out, the

others will

•burn with their original intensities

•all go out

•become dimmer

•become brighter

37.

38. Electrical leads and insulation on a motor should be painted with

•heat -resisting aluminum

•insulating white lead

•heat-resisting acrylic

•insulating varnish

38.

39. Which of the following physical characteristics does a wound-rotor induction motor

possess that a squirrel-cage motor does not?

•Centrifugal switch

•Slip rings

•End rings

•End plates

39.

40. Why should you use a high impedance multimeter when troubleshooting electronic

equipment?

•whenever a low impedance meter is not available, regardless of the components being tested

•to prevent excess current flow through the meter that would damage it

•so as not to load down the circuit and obtain erroneous voltage readings

•can be used for AC measurements only and a low resistance meter for DC measurements

40.

41. Air gap readings should be periodically taken for electrical generation equipment. The best

tool to use to take these measurement is a

•tapered, long blade gage

•inside micrometer

41.

42. Which test on a transformer provides information about the regulation, efficiency and

heating under load condition?

•Short circuit test

•Open circuit test

•Hopkinson circuit test

•Back to back test

42.

43. It is a type of electrical fault that happens when a phase conductor is completely or

partially interrupted:

•Earth fault

•Phase failure fault

•Short circuit fault

•Open circuit fault

43.

44. The windings of electric generators during short idle periods should be

•relieved of all capacitive charge by grounding the conductors

•allowed to cool slowly to ambient temperatures

•kept warm by using strip or space heaters

•flashed with direct current to remove any residual magnetism

44.

45. The part of the shipboard electrical system used to control the distribution of power to the

branch circuits, is the

•disconnect links

•governor relay box

•main switchboard

•bridge control panel

45.

46. A temperature instrumentationsystem for an engine room console consistes of a

resistance temperature detector(RTD), a measuring bridge circuit, and a meter(or alarm

circuit). Which of the following statements is true concerning the measuring bridge circuit?

•The voltage across the center of the resistance bridge is always constant

•The input voltage varies in a linear fashion with temperature

•The resistance bridge is said to be balanced when its output voltage is zero

•The input voltage of the resistance bridge is the constant temperature signal

46.

47. In the event of a power failure during cargo loading operations, which of the following can

stop the movement of an electric powered cargo winch?

•A spring set brake

•A manual override switch

•A hand operated band brake

•The weight of the load on the boom

47.

48. A device which can be used to check the calibration of a circuit breaker is a

•standard digital multimeter

•portable low voltage high current testing unit

•clamp-on voltmeter

•500 volt megohmmeter

48.

49. Before reassembling any machinery, what should you do?

•clean any corroded surfaces and file all burrs smooth

•apply a heavy coat of oil to all mating surfaces

•replace all bearings regardless of length of service

•coat all parts with alemite grease

49.

50. Air gap readings should be periodically taken for electrical generation equipment. The best

tool to use to take these measurements is a

•cloth (non-metallic) tape measure

•tapered, long blade gage

•inside micrometer

•dial indicator

50.

51. A semiconductor that decreases in resistance with an increase in temperature is known

as?.

•resistor

•thermopile

•thermistor

•diode

51.

52. What should be done to protect the rotor of a motor disassembled for maintenance or

overhaul?

•it must be returned to the frame as soon as the bearings are removed

•it must be stowed upright on its shaft

• it must be suspended by wire slings in one corner of the shop

•it must be supported by two "V" notched wood blocks

52.

53. What is a variable-resistance component used as a control device in electrical circuit?

•Reactance

•Potentiometer

•Dimmer switch

•Resistance

53.

54. What kind of electrical cable that is widely used and is highly resistant to mechanical

damage?

•Sheathed cable which is free of metal.

•Aluminum cable covered with insulation.

•Cable with plastic insulation

•Cable with lead cover.

54.

55. When trouble shooting electronic equipment, what is the first step to be taken before

testing the circuit voltage?

•set the meter to the lowest range

•check the voltage supply from the power source

•remove the suspected component

•check the current flow through the circuit

55.

56. The purpose of a main switchboard circuit breaker's reverse-power trip is to

•prevent low voltage trip out

•prevent alternator motorization

•protect the circuit breaker blow out coil

•prevent air circuit overload

56.

57. Temporary repairs to an open DC propulsion armature coil can be made by

•connecting the coil ends directly to a pair of negative brushes

•removing the sparking brushes

•disconnecting coil ends, insulating each, and short circuiting the two commutator bars

•grounding the coil ends and short circuiting the commutator bar

57.

58. When charging lead-acid batteries, you should reduce the charging rate as the battery

nears its full charge capacity to

•increase lead peroxide formation

•prevent excessive gassing and overheating

•reduce lead sulfate deposits

•allow equalization of cell voltages

58.

59. When shipboard electrical distribution circuits are connected in parallel, additional parallel

circuits will cause the total circuit resistance to

•increase, causing a decrease in the line voltage

•increase, causing a drop in the line current

•decrease, causing an increase in the line voltage

•decrease, causing an increase in the line current

59.

60. What is a device that converts fluid powers into linear mechanical force and motion that

consists of a movable piston, connecting rod, and plunger operating in a cylindrical cavity?

60. What is a device that converts fluid powers into linear mechanical force and motion that

consists of a movable piston, connecting rod, and plunger operating in a cylindrical cavity?

•Cylinder

•Diaphragm

•Actuator

60.

61. During maintenance of circuit breakers,

•always smooth roughened contact surfaces with a file

•inspect for wear and misalignment of main contacts

•never pass more than rated breaker current through the overload heater element

•always apply a thin film of oil on contact surfaces

61.

62. What is used in most for starting three-phase induction motors of five (5) horsepower or

less ?

•across-the-line starters

•reactor starters

•autotransformer starters

•resistor starters

62.

63. Periodic testing of circuit breakers is necessary to assure that a correct rated and properly

installed unit

•be able to withstand at least 125% of applied voltage

•does not exceed its interrupting capacity

•will continue to provide the original degree of protection

•can trip faster as load increases

63.

64. You are testing the insulation in an AC generator with with a megohmeter. the resistance

value of a dry, clean winding will_

•remain constant as the temperature of the windings increases

•continue to drop as the potential is maintained, becoming fairly steady after 5 to 7 minutes

•continue to rise as the test potential is maintained, becoming fairly steady as the leakage

current stabilizes

•stabilize after approximately 2 to 4 minutes of fluctuation

64.

65. Which of the following data is required to draw the circle diagram for an induction motor?

•No load test only

•Bolck rotor test, no load test and stator resistance test

•Block rotor test and no load test

•Block rotor test only

65.

66. The removal of paint from electrical equipment such as generators, should be cautiously

undertaken because

•paint dust build up has a tendency to cause corrosion

•the paint dust is composed of abrasive and semi-conducting materials which impair

insulation

•phase windings frequently become isolated from each other due to dust interference at the

terminals

•the mechanical shock of paint removal lessens the di-electric strength of the insulation

66.

67. A reversible electric motor with worm gear that is connected to the flywheel to position

engine parts is the

•turning gear

•wheel gear

•reversing gear

•valve gear

67.

68. If a small electric motor is immersed in salt water it should be I. washed in fresh water II.

dried in an oven III. blow air until it dries

•neither I and III

•Il only

•I only.

•both I and II

68.

69. To carry out an insulation resistance test, one terminal of the megohmmeter should be

connected to the winding, with the other terminal being connected to the

•frame of the machine

•power supply

•armature

•variable resistor

69.

70. Before working on an electric motor starter panel located on the main deck, what should

you do FIRST?

•Spray the gasket surface with a solvent

•Heat the switchboard to remove moisture

•Open the circuit breaker and tag out

•Drain condensate from the box

70.

71. A fuse the blows often should be replaced only with a fuse of __.

•higher current and voltage rating,

•higher current and lower voltage rating

•lower current and higher voltage rating

•the recommended current and voltage rating

71.

72. Electrical Insulating rubber gloves should be dielectrically tested every how many months?

•6 months

•9 months

•3 months

•12 months

72.

73. It is a type of temperature sensor that has the characteristic of being very accurate, linear

and has a good long term stability.

•Thermistors

•RTD'S

•Silicone junction temperature sensors

•Thermocouple

73.

74. A self-excited DC generator fails to come up to its normal 440 volts. What could be the

probable cause?

•low armature speed

•excessive brush tension

•low rheostat resistance

•excessive residual magnetism

74.

75. A common type of protective covering used on electrical conductors is,

•Plain paper

•Silver sheating

•Fibrous braid

•Babbit sheating

75.

76. The air gap provided in induction motors should be checked periodically with a feeler gage

to detect an unequal air gap and

•Hysteresis losses

•Decreased motor magnetizing current

•Mechanical damage to rotor

•Increased power factor

76.

77. A temperature instrumentation system for an accomodation reefer room consists of a

resistance temperature detector (RTD), a measuring bridge circuit and a meter or alarm circuit.

Which of the following is true concering the measuring bridge circuit ?

•The input voltage in a linera fashion with the temperature

•The voltage across the conter of the resistance bridge is always constant

•The input voltage of the resistance bridge is the constant temperature signal

•The ressistance bridge is said to be balanced when its output voltage is zero

77.

78. Electrically operated safety devices on auxiliary diesel engines functions to stop the engine

•shutting off air supply

•shutting off lube oil supply

•shutting off cooling water supply

•shutting off fuel supply

78.

79. A molded-case circuit breaker provides protection against short circuits by using alan ?

•shading coil

•electromagnet

•arc quencher

•burn away strip

79.

80. The proper way to apply plastic electrical tape to an electric cable splice is to

•apply the tape in one non -overlapping layer only

•apply tape to the braided cover, but avoid touching it

•wind the tape so that each turn overlaps the turn before it

•heat the tape with a soldering iron for good bonding

80.

81. The division of kilowatt load between two paralleled alternators is determined by the ?.

•amount of field excitation to the leading machine

•number of field poles per alternator

•amount of field excitation to the lagging machine

•load-speed characteristics of the governors

81.

82. What is the result if the solenoid coil burns on a cargo winch with an electrical brake?

•The brake will be set by spring force.

•The motor will overspeed and burn up.

•Nothing will happen; the winch will continue to operate as usual.

•The load suspended from the cargo boom will fall.

82.

83. The air gap provided an induction motor should be checked periodically with a feeler gage

to detect

•any increase in rotor bearing wear

•increase in apparent power factor

•an increase in hysteresis loss

•any decrease in motor magnetizing current

83.

84. Encrusted dirt accumulated inside a motor should be removed with a

•Hammer and chisel

•Paint scraper

•Pointed welding rod

•Fiber scraper

84.

85. A temperature instrumentation system to an engine room console consists of a resistance

temperature detector (RTD), a measuring bridge circuit , and a meter (or alarm circuit). Which of the following statements is true concerning the measuring bridge circuit?

•The voltage across the center of the resistance bridge is always constant

•The input voltage of the resistance bridge is the constant temperature signal

•The input voltage varies in a linear fashion with temperature

•The resistance bridge is said to be balanced when its output voltage is zero

85.

86. When a replacing a fuse with one of a higher rating than the original, which of the

following is true?

•It endangers the apparatus it is supposed to protect

•It increases the efficiency of the equipment by allowing more current to be used

•It reduces the possibility of short circuits

•It creates a larger voltage drop in the circuit being protected

86.

87. The purpose of a motor under voltage protection device is to

•trip the load off the motor in case of fire

•start the motor at a very low voltage

•prevent high armature current when power is restored

•protect personnel from from low voltage shock

87.

88. The power scale of circle diagram of an induction motor can be found from

•stator resistance test

•stator none resistance test

•short-circuit test only.

•no load test only

88.

89. What electrical apparatus can test insulating efficiency in an electric installation?

•Ammeter

•Potentiometer

•Volt meter

•Megger tester

89.

90. When reading electrical motor controller diagrams, it helps to know that

•current paths in the control circuit are drawn as heavy lines and in the power circuit as lighter

lines

•current paths in the power circuit are drawn as heavy lines and in control circuit as lighter

lines

•circuits subject to 500 volts or greater are drawn as heavy lines and below 500 volts as lighter

lines

•circuits subject to 500 volts or greater are drawn as light lines and below 500 volts as heavy

lines

90.

91. What devices is fitted to prevent the generator windings from absorbing moisture while at

standstill?

•Generator heater

•Windings heater

•Motor heater

•Space heater

91.

92. Any electric motor can be constructed to be?

•ground proof

•short proof

•explosion proof

•overload proof

92.

93. A common type of protective covering used on electrical conductors is

•silver sheathing

•babbitt sheathing

•plain paper

•rubber or plastic

93.

94. Which of the following statements concerning the maintenance of solid-silver Contacts in

relay and auxiliary control circuits is correct?

•When necessary, they should always be dressed with a wire wheel

•When necessary, they should be spray painted with electrical shellac

•When black silver oxide is present. It should always be removed from the contact surface

with coarse sandpaper

•They should be filed with a fine-cut file when projections extend beyond the contact

surface

94.

95. What can you do if the generator is exposed to rain or any water?

•Run the system for 1 hour to test the performance.

•Check the coil if insulation is pilled up.

•Use hygrometer to test the moisture.

•Make a megger test

95.

96. What is the cause when an alternator failed to produce line voltage?

•oxidized slip rings

•a closed circuit breaker

•improperly staggered brushes

•exciter generator failure

96.

97. Moisture as a result of condensation occurring inside of the cargo winch master switches,

can be reduced by?

•using strip heaters inside the switch box

•installing a light bulb in the pedestal stand

•coating the switch box internals with epoxy sealer

•venting the switch box regularly

97.

98. Regulations require each motor controller to have a wiring diagram located

•in the engineering office

•on the inside of the controller door

•in the spare parts locker

•outside door in engine room

98.

99. A device which can be used to check the calibration of a circuit breaker is a

•portable low voltage high current testing unit

•standard digital multimeter

•500 volt megohmmeter

•clamp-on voltmeter

99.

100. Which of the following statements concerning analog and digital devices are correct?

•Operations in a digital device are performed simultaneously.

•Analog devices are superior in accuracy compared to digital devices.

•The variables in digital systems are fixed quantities and the variables in analog systems are

continuous quantities.

•There are no basic differences between the two systems.

100.

101. When a megohmmeter is being used to test insulation resistance, current leakage along

the surface of the insulation is indicated by the megohmmeter's pointer ?

•fluctuating around a constant resistance reading

•continually rising as test voltage is applied

•dipping toward zero then raising slowly

•kicking slightly down scale as voltage is applied

101.

102. In using the Rheostat, what do you call the circuit of the motor to adjust the speed?

•Motor of synchronous type

•Induction motor with squirrel gauge.

•Induction motor with wound-rotor

•Breaking motor with generator capability.

102.

103. How can you restore the charge of a lead-acid battery?

•passing an alternating electric current through the cell

•adding acid to the electrolyte

•by adding water to the electrolyte

•passing a direct electric current through the cell

103.

104. In an impressed current cathodic protection system, what is anode

•connected to the hull and deteriorates with time

•connected to the hull but does not waste away

•insulated from the hull and does not waste away,

•insulated from the hull but deteriorates with time

104.

105. Complete maintenance of electrical motors should include periodic checks for machine

•watertight integrity

•speed droop

•vibration

•reactive power

105.

106. The automatic voltage regulators provide on switch boards has function to

•vary the field excitation to the generators

•regulate diesel generator engine speed,

•regulate the AC load on the generator

protect the switch fromecessive current

106.

107. If a delicate component must be soldered into a circuit the component may be protected

from the heat of the soldering process by.

•operating the soldering gun not more than 60 seconds at a time

•coating the leads to be soldered with a light oil film

•pre-oxidizing the leads to be soldered

•using a thermal shunt

107.

108. What maximum voltage can Class 00 electrical insulating rubber gloves can be used?

•6600 volts

•500 volts

•1000 volts

7500 volts

108.

109. Which of the following statements represents the FIRST step in seating new brushes on

slip rings?

•Press the brushes against the slip ring with a woodblock.

•Increase brush pressure and run at no load for 3 to 4hours.

•Apply seating compound under the brushes and run atno load for 2 hours.

•Lay sandpaper between the brush and the slip ring and slide the sandpaper back and forth

under the brush.

109.

110. Which of the following statements is true concerning the cleaning of electrical contacts?

•Magnetic brushes should be used to remove metallic dust.

•Delicate parts should be cleaned with a brush and an approved safety solvent.

•The contact surfaces should be greased to increase contact resistance.

•Compressed air should be used to blow out metallic dust.

110.

111. What indicates the third color band on a resistor?

•number of zeros following the first two significant figures in the resistance value

•first significant figure of the resistance to give the tolerance of the resistor

•tolerance of the resistor following the first significant figures in the resistance value

•second significant figure of the resistance to give the value of zeros

111.

112. What would indicate ground in a particular phase 3 - phase low voltage distribution

system?

•bright switchboard ground detecting light

•High switchboard watt meter

•Low Switchboard watt meter

•dark or dim switchboard ground detecting light

112.

113. While trouble shooting a circuit in an engine room central control console, a resistor is

suspected of being faulty. Which of the following precautions must be observed if an ohm

meter is to be use to check its value?

•Resistor circuit must be de-energized and at least one end of the component isolated

•Correct polarity must be observed because reverse bias will damage the component

•Meter leads must not be twisted so as to cancel out the individual magnetic fields

•The meter case must be grounded prior to attaching the leads

113.

114. Which of the following statements best describes the material known as varnished

cambric?

•Rubber insulation coated with a layer of tin.

•Cotton cloth coated with insulating varnish.

•Felted asbestos sealed with varnish.

•Paper impregnated with mineral oil, specially wrapped with nonmetallic tape, and coated

with varnish.

114.

115. What is the first step to properly use a hook-on-type voltammeter in checking current

flow?

•connect the voltage test leads to the appropriate terminals

•hook the jaws of the instrument around the insulated conductor

•de-energize the circuit to allow connection of the instrument in series

•short the test leads and calibrate the instrument to zero

115.

116. Upon failure of the normal power supply, the emergency generator is placed on the line

by the

•power failure alarm bus

•bus the feeder

•line connection feeder

•automatic bus transfer devise

116.

117. Where a thermal-acting breaker is required to be used in an area of unusually high, low,

or constantly fluctuating temperatures, an ambient compensating element must be used.

What does this element consist of?

•cylindrical spring on the contact arm

•conical spring on the contact arm

•second bimetal element

•second electromagnet

117.

118. Which of the listed precautions should be observed before spraying liquid solvent on the

insulation of an electric motor?

•Preheat the insulation to assist in cleaning.

•Slow the motor down to low speed.

•Secure all ventilation in the area.

•Disconnect the motor from the power source.

118.

119. The electrolyte in a lead-acid storage battery consists of distilled water and

•hydrogen chloride

•calcium chloride

•muriatic acid

•sulfuric acid

119.

120. The insulation resistance of electric equipment and machinery should be tested for

lowest normal insulation valves

•Immediately after starting up the machine

•Every 30 days whether the machine is in use or

•Every time the brush rigging is adjusted

•immediately after shutting down of the machine

120.

121. How much is the typical resistance of the body from hand to foot when dry?

•100 ohms

•1500 ohms

•500 ohms

•1000 ohms

121.

122. How will you remove a tubular fuse from a fuse panel with

•a pair of insulated metal pliers

•any insulated object

•a screwdriver

•fuse pullers

122.

124. When a lead-acid battery begins gassing freely while receiving a normal charge, what

should you do when charging?

•be decreased

•be increased

•remain unchanged

•shut off

123.

125. In the circle diagram for induction motor, the diameter of the circle represents

•line voltage

•rotor current

•slip

•running torque

124.

126. What is a three-layer bidirectional device used primarily as a trggering device with

junctions heavily and equally doped?

•Triac

•Op-Amps.

•Diac

•UJT

125.

127. Two contributors of electronic console failures are heat and vibration. To combine some

of their effect, preventive maintenance procedures should include

•periodic changing or cleaning of console ventilation and control room air conditioning

filters

•systematic rotation of circuit cards with those from spares to allow component cooling

•daily inspection of console foundation bolts

•all of the above

Reset

C7 rj

Total questions: 125

Worksheet time: 1hrs 3mins

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