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127問 • 1年前
  • Jeo Clyde Arizo
    • 通報

    問題一覧

  • 1

    A common type of protective covering used on electric conductors is _____

    fibrous braid

  • 2

    Any electric motor can be constructed to be?

    Explosion proof

  • 3

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

    sulfuric acid

  • 4

    What is used in most for starting three-phase induction motors of five (5) horsepower less?

    across-the-line starters

  • 5

    The air gap provided in induction motors should be checked periodically with a feeler gage to detect an unequal air gap and ______.

    Mechanical damage to rotor

  • 6

    You are testing the insulation in an AC generator with with a megohmeter. the resistance value of a dry, clean winding will ______.

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

  • 7

    The insulation resistance of electric equipment and machinery should be tested for lowest normal insulation valves _____.

    immediately after shutting down of the machine

  • 8

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

  • 9

    What should be done to protect the rotor of a motor disassembled for maintenance of overhaul?

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

  • 10

    A reversible electric motor with worm gear that is connected to the flywheel to position engine parts is the _____ .

    turning gear

  • 11

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

    Speedometer

  • 12

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

    low armature speed

  • 13

    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

  • 14

    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?

    heat sensitive thermography

  • 15

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

    Potentiometer

  • 16

    What would indicate ground in a particular phase 3 - phase low voltage distribution system?

    dark or dim switchboard ground detecting light

  • 17

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

    6 months

  • 18

    The greatest single cause of electrical failure is ____.

    The breakdown of insulation

  • 19

    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 ______.

    continuity

  • 20

    Which test on a transformer provides information about the regulation, efficiency and heating under load condition?

    Back to back test

  • 21

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

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

  • 22

    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 statements is true concerning the measuring bridge circuit?

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

  • 23

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

    on the inside of the controller door

  • 24

    A switchboard for an AC electrical system requires the use of which of the following devices?

    Frequency meter

  • 25

    What motor is fitted with an instantaneous overload relay?

    Winch

  • 26

    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?

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

  • 27

    A common type of protective covering used on electrical conductors is

    rubber or plastic

  • 28

    What is a three-layer bidirectional device used primarily as a trggering device with junctions heavily and equally doped?

    Diac

  • 29

    Encrusted dirt accumulated inside a motor should be removed with a ______

    Fiber scraper

  • 30

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

    portable low voltage high current testing unit

  • 31

    Air gap readings should be periodically taken for electrical generation equipment. The best tool to use to take these measurements is a ______.

    tapered, long blade gage

  • 32

    How should controller contacts be routinely cleaned?

    wiping with a clean dry cloth

  • 33

    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.

  • 34

    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

  • 35

    When the equivalent circuit diagram of double squirrel-cage induction motor is constructed the two cages can be considered _____.

    in parallel

  • 36

    It is a type of temperature sensor that has the characteristic of being very accurate, linear and has a good long term stability.

    RTD'S

  • 37

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

    megger

  • 38

    What kind of device that has two pieces of metal joined together so that when its junction is heated, a voltage is produced?

    Thermocouple

  • 39

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

    Triangle

  • 40

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

    Make a megger test

  • 41

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

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

  • 42

    To check the three line fuses of three-phase system consisting of a three-phase motor, must _______.

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

  • 43

    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?

    second bimetal element

  • 44

    Which of the following physical characteristics does a wound-rotor induction motor possess that a squirrel-cage motor does not?

    Slip rings

  • 45

    Which of the following statements concerning the maintenance of solid silver Contacts in relay and auxiliary control circuits is correct?

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

  • 46

    Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor?

    Disconnect the motor from the power source.

  • 47

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

    the recommended current and voltage rating

  • 48

    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.

  • 49

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

    Kept warm by using strip or space heaters

  • 50

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

    500 volts

  • 51

    What may happen to the components of a winch master control switch, if the cover gasket becomes deteriorated?

    Rapid corrosion of switch components.

  • 52

    Which of the following safest precautionary measure is to be done prior working on the motor of the cargo winch?

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

  • 53

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

    fuse pullers

  • 54

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

    any increase in rotor bearing wear

  • 55

    A safety device in an electrical circuit consisting of metal strip that melts when the current exceeds the safe level is called ____.

    fuse

  • 56

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

    electromagnet

  • 57

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

    prevent alternator motorization

  • 58

    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

  • 59

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

    prevent high armature current when power is restored

  • 60

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

    short-circuit test only

  • 61

    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

  • 62

    An electric tachometer receives the engine speed signal from?

    bimetallic sensing device

  • 63

    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

  • 64

    Before working on an electric motor starter panel located on the main deck, what should you do FIRST?

    Open the circuit breaker and tag out

  • 65

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

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

  • 66

    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

    I only

  • 67

    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

    I only

  • 68

    A temperature instrumentation system 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 resistance bridge is said to be balanced when its output voltage is zero

  • 69

    When trouble shooting electronic equipment, what is the first step to be taken before testing the circuit voltage?

    check the voltage supply from the power source

  • 70

    What kind of electrical cable that is widely used and is highly resistant to mechanical damage?

    Aluminum cable covered with insulation.

  • 71

    What is a device that changes an input signal of one type into an output signal of a different type that is proportional to the original input?

    Transducer

  • 72

    If a delicate component must be soldered into a circuit the component may be protected from the heat of the soldering process by _____.

    using a thermal shunt

  • 73

    The removal of paint from electrical equipment such as generators, should be cautiously undertaken because _____.

    the paint dust is composed of abrasive and semi-conducting materials which impakt insulation

  • 74

    Which of the following materials is recommended for finishing the slip rings after grinding or turning?

    crocus cloth

  • 75

    When changing tubular fuses always use a _____.

    Fuse puller

  • 76

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

    load-speed characteristics of the governors

  • 77

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

    portable low voltage high current testing

  • 78

    What devices is fitted to prevent the generator windings from absorbing moisture while at standstill?

    Space heater

  • 79

    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

  • 80

    During maintenance of circuit breakers, _____.

    inspect for wear and misalignment of main contacts

  • 81

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

    The variables in digital systems are fixed quantities and the variables in analog systems are continuous quantities.

  • 82

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

    wheel puller

  • 83

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

    a dangerously explosive gas being liberated

  • 84

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

    Megger tester

  • 85

    What is the first step to properly use a hook-on-type volt/ammeter in checking current flow?

    hook the jaws of the instrument around the insulated conduct

  • 86

    What kind of instrument used to measure the specific gravity, or "charge" of the electrolyte of a storage battery?

    Hydrometer

  • 87

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

    shutting off fuel supply

  • 88

    When a lead-acid battery begins gassing freely while receiving a normal charge, what should you do when charging?

    be decreased

  • 89

    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?

    kicking slightly down scale as voltage is applied

  • 90

    A capacitor can be tested using a megohmmeter or an ohmmeter, if the meter is connected to a shorted capacitor, the meter pointer should ______.

    immediately deflect to and remain at zero

  • 91

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

    Bolck rotor test, no load test and stator resistance test

  • 92

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

    electromagnet

  • 93

    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

  • 94

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

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

  • 95

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

    will continue to provide the original degree of protection

  • 96

    Which of the following statements best describes the material known as varnished cambric?

    Cotton cloth coated with insulating varnish.

  • 97

    When a replacing a fuse with one of a higher rating than the original, which of the following is true?

    endangers the apparatus it is supposed to protect

  • 98

    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 ____.

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

  • 99

    What does the variable resistance placed in the rotor circuit of a wound-rotor induction motor provide?

    speed control

  • 100

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

    vary the field excitation to the generators

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    問題一覧

  • 1

    A common type of protective covering used on electric conductors is _____

    fibrous braid

  • 2

    Any electric motor can be constructed to be?

    Explosion proof

  • 3

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

    sulfuric acid

  • 4

    What is used in most for starting three-phase induction motors of five (5) horsepower less?

    across-the-line starters

  • 5

    The air gap provided in induction motors should be checked periodically with a feeler gage to detect an unequal air gap and ______.

    Mechanical damage to rotor

  • 6

    You are testing the insulation in an AC generator with with a megohmeter. the resistance value of a dry, clean winding will ______.

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

  • 7

    The insulation resistance of electric equipment and machinery should be tested for lowest normal insulation valves _____.

    immediately after shutting down of the machine

  • 8

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

  • 9

    What should be done to protect the rotor of a motor disassembled for maintenance of overhaul?

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

  • 10

    A reversible electric motor with worm gear that is connected to the flywheel to position engine parts is the _____ .

    turning gear

  • 11

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

    Speedometer

  • 12

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

    low armature speed

  • 13

    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

  • 14

    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?

    heat sensitive thermography

  • 15

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

    Potentiometer

  • 16

    What would indicate ground in a particular phase 3 - phase low voltage distribution system?

    dark or dim switchboard ground detecting light

  • 17

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

    6 months

  • 18

    The greatest single cause of electrical failure is ____.

    The breakdown of insulation

  • 19

    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 ______.

    continuity

  • 20

    Which test on a transformer provides information about the regulation, efficiency and heating under load condition?

    Back to back test

  • 21

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

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

  • 22

    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 statements is true concerning the measuring bridge circuit?

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

  • 23

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

    on the inside of the controller door

  • 24

    A switchboard for an AC electrical system requires the use of which of the following devices?

    Frequency meter

  • 25

    What motor is fitted with an instantaneous overload relay?

    Winch

  • 26

    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?

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

  • 27

    A common type of protective covering used on electrical conductors is

    rubber or plastic

  • 28

    What is a three-layer bidirectional device used primarily as a trggering device with junctions heavily and equally doped?

    Diac

  • 29

    Encrusted dirt accumulated inside a motor should be removed with a ______

    Fiber scraper

  • 30

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

    portable low voltage high current testing unit

  • 31

    Air gap readings should be periodically taken for electrical generation equipment. The best tool to use to take these measurements is a ______.

    tapered, long blade gage

  • 32

    How should controller contacts be routinely cleaned?

    wiping with a clean dry cloth

  • 33

    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.

  • 34

    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

  • 35

    When the equivalent circuit diagram of double squirrel-cage induction motor is constructed the two cages can be considered _____.

    in parallel

  • 36

    It is a type of temperature sensor that has the characteristic of being very accurate, linear and has a good long term stability.

    RTD'S

  • 37

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

    megger

  • 38

    What kind of device that has two pieces of metal joined together so that when its junction is heated, a voltage is produced?

    Thermocouple

  • 39

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

    Triangle

  • 40

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

    Make a megger test

  • 41

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

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

  • 42

    To check the three line fuses of three-phase system consisting of a three-phase motor, must _______.

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

  • 43

    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?

    second bimetal element

  • 44

    Which of the following physical characteristics does a wound-rotor induction motor possess that a squirrel-cage motor does not?

    Slip rings

  • 45

    Which of the following statements concerning the maintenance of solid silver Contacts in relay and auxiliary control circuits is correct?

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

  • 46

    Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor?

    Disconnect the motor from the power source.

  • 47

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

    the recommended current and voltage rating

  • 48

    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.

  • 49

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

    Kept warm by using strip or space heaters

  • 50

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

    500 volts

  • 51

    What may happen to the components of a winch master control switch, if the cover gasket becomes deteriorated?

    Rapid corrosion of switch components.

  • 52

    Which of the following safest precautionary measure is to be done prior working on the motor of the cargo winch?

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

  • 53

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

    fuse pullers

  • 54

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

    any increase in rotor bearing wear

  • 55

    A safety device in an electrical circuit consisting of metal strip that melts when the current exceeds the safe level is called ____.

    fuse

  • 56

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

    electromagnet

  • 57

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

    prevent alternator motorization

  • 58

    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

  • 59

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

    prevent high armature current when power is restored

  • 60

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

    short-circuit test only

  • 61

    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

  • 62

    An electric tachometer receives the engine speed signal from?

    bimetallic sensing device

  • 63

    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

  • 64

    Before working on an electric motor starter panel located on the main deck, what should you do FIRST?

    Open the circuit breaker and tag out

  • 65

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

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

  • 66

    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

    I only

  • 67

    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

    I only

  • 68

    A temperature instrumentation system 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 resistance bridge is said to be balanced when its output voltage is zero

  • 69

    When trouble shooting electronic equipment, what is the first step to be taken before testing the circuit voltage?

    check the voltage supply from the power source

  • 70

    What kind of electrical cable that is widely used and is highly resistant to mechanical damage?

    Aluminum cable covered with insulation.

  • 71

    What is a device that changes an input signal of one type into an output signal of a different type that is proportional to the original input?

    Transducer

  • 72

    If a delicate component must be soldered into a circuit the component may be protected from the heat of the soldering process by _____.

    using a thermal shunt

  • 73

    The removal of paint from electrical equipment such as generators, should be cautiously undertaken because _____.

    the paint dust is composed of abrasive and semi-conducting materials which impakt insulation

  • 74

    Which of the following materials is recommended for finishing the slip rings after grinding or turning?

    crocus cloth

  • 75

    When changing tubular fuses always use a _____.

    Fuse puller

  • 76

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

    load-speed characteristics of the governors

  • 77

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

    portable low voltage high current testing

  • 78

    What devices is fitted to prevent the generator windings from absorbing moisture while at standstill?

    Space heater

  • 79

    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

  • 80

    During maintenance of circuit breakers, _____.

    inspect for wear and misalignment of main contacts

  • 81

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

    The variables in digital systems are fixed quantities and the variables in analog systems are continuous quantities.

  • 82

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

    wheel puller

  • 83

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

    a dangerously explosive gas being liberated

  • 84

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

    Megger tester

  • 85

    What is the first step to properly use a hook-on-type volt/ammeter in checking current flow?

    hook the jaws of the instrument around the insulated conduct

  • 86

    What kind of instrument used to measure the specific gravity, or "charge" of the electrolyte of a storage battery?

    Hydrometer

  • 87

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

    shutting off fuel supply

  • 88

    When a lead-acid battery begins gassing freely while receiving a normal charge, what should you do when charging?

    be decreased

  • 89

    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?

    kicking slightly down scale as voltage is applied

  • 90

    A capacitor can be tested using a megohmmeter or an ohmmeter, if the meter is connected to a shorted capacitor, the meter pointer should ______.

    immediately deflect to and remain at zero

  • 91

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

    Bolck rotor test, no load test and stator resistance test

  • 92

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

    electromagnet

  • 93

    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

  • 94

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

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

  • 95

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

    will continue to provide the original degree of protection

  • 96

    Which of the following statements best describes the material known as varnished cambric?

    Cotton cloth coated with insulating varnish.

  • 97

    When a replacing a fuse with one of a higher rating than the original, which of the following is true?

    endangers the apparatus it is supposed to protect

  • 98

    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 ____.

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

  • 99

    What does the variable resistance placed in the rotor circuit of a wound-rotor induction motor provide?

    speed control

  • 100

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

    vary the field excitation to the generators