The operator of electrical motors should keep a constant check on the loads they carry because _____________. A. low loads necessitate frequent insulation cleaning B. exceeding nameplate values shortens useful life C. energy is wasted if full loading is not utilized D. power factor correction methods are load dependent

The operator of electrical motors should keep a constant check on the loads they carry because _____________. A. low loads necessitate frequent insulation cleaning B. exceeding nameplate values shortens useful life C. energy is wasted if full loading is not utilized D. power factor correction methods are load dependent
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Answer: B
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Electrical machinery insulation will break down more rapidly due to _________________. A. low loading of motors and generators B. frequent megger testing C. high temperatures and vibration D. high operating frequencies

Description : Electrical machinery insulation will break down more rapidly due to _________________. A. low loading of motors and generators B. frequent megger testing C. high temperatures and vibration D. high operating frequencies

Last Answer : Answer: C

In an alternating current electrical system, a low system power factor is a direct sign of _____________. A. wasted energy B. efficient operation C. a short in the exciter field windings D. an excessive number of minor system grounds

Description : In an alternating current electrical system, a low system power factor is a direct sign of _____________. A. wasted energy B. efficient operation C. a short in the exciter field windings D. an excessive number of minor system grounds

Last Answer : Answer: A

An insulation resistance test is performed on a particular piece of electric equipment. In addition to the resistance reading, what information listed below should be entered in the electrical log? A. The maximum allowable operating temperature of the machine. B. The temperature of the machine at the time the resistance reading was taken. C. The normal temperature rise of the machine. D. The complete nameplate data from the resistance test instrument used to obtain the reading.

Description : An insulation resistance test is performed on a particular piece of electric equipment. In addition to the resistance reading, what information listed below should be entered in the electrical log? A. ... D. The complete nameplate data from the resistance test instrument used to obtain the reading.

Last Answer : Answer: B

Electrical failures in motors are caused by the breakdown of insulation, which may be caused by _____________. A. penetration of moisture B. accumulation of dirt C. overheating D. all of the above

Description : Electrical failures in motors are caused by the breakdown of insulation, which may be caused by _____________. A. penetration of moisture B. accumulation of dirt C. overheating D. all of the above

Last Answer : Answer: D

The greatest detrimental effect on idle electrical equipment, such as cargo pump motors, is the _____________. A. loss of residual magnetism B. absorption of moisture in the insulation C. insulation varnish flaking D. dirt collecting on the windings

Description : The greatest detrimental effect on idle electrical equipment, such as cargo pump motors, is the _____________. A. loss of residual magnetism B. absorption of moisture in the insulation C. insulation varnish flaking D. dirt collecting on the windings

Last Answer : Answer: B

Cleaning of electrical insulation should be _____________. A. done every six months B. accomplished every 12 months C. determined by need and not the calendar D. performed whenever the electrician is not otherwise busy

Description : Cleaning of electrical insulation should be _____________. A. done every six months B. accomplished every 12 months C. determined by need and not the calendar D. performed whenever the electrician is not otherwise busy

Last Answer : Answer: C

A generator has been exposed to water and is being checked for its safe operation. Therefore, it is necessary to _______________. A. check for shorted coils with a growler B. take moisture readings with a hydrometer C. test insulation values with a megger D. ground the commutator, or slip rings and run it at half load for 12 hours

Description : A generator has been exposed to water and is being checked for its safe operation. Therefore, it is necessary to _______________. A. check for shorted coils with a growler B. take moisture readings with a ... a megger D. ground the commutator, or slip rings and run it at half load for 12 hours

Last Answer : Answer: C

The greatest single cause of electrical failures is ______. A. the breakdown of insulation B. overcurrent C. high inductance D. too frequent testing

Description : The greatest single cause of electrical failures is ______. A. the breakdown of insulation B. overcurrent C. high inductance D. too frequent testing

Last Answer : Answer: A

Capacitors can be used in electric distribution systems to improve power factor. This is accomplished by seesawing energy between the capacitor and the _____________. A. generator B. inductive loads C. resistive loads D. all of the above

Description : Capacitors can be used in electric distribution systems to improve power factor. This is accomplished by seesawing energy between the capacitor and the _____________. A. generator B. inductive loads C. resistive loads D. all of the above

Last Answer : Answer: B

Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Description : Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings

Last Answer : Answer: D

The insulation resistance of a DC motor is observed to be 15 MΩ at a temp. of 70°C. what is its value corrected to 40°C. the correction factor for 70°C is 8.0.

Description : The insulation resistance of a DC motor is observed to be 15 MΩ at a temp. of 70°C. what is its value corrected to 40°C. the correction factor for 70°C is 8.0. 

Last Answer : Observed resistance at 70°C – 15 MΩ. Temperature correction factor – 8. Rm = kt * Rt           kt – correction factor. Rm = 8 * 15          Rt – resistance measured at +°C. Rm = 120 MΩ.       Rm – corrected value to 40°C The IR of DC motor corrected to 40°C is 120 MΩ. 

When working on electrical circuits containing large capacitors, in addition to deenergizing the circuit, which of the listed precautions should also be taken? A. Keep all radio equipment away. B. Measure capacitor insulation resistance. C. Ground the capacitor terminals. D. Check capacitor circuit polarity.

Description : When working on electrical circuits containing large capacitors, in addition to deenergizing the circuit, which of the listed precautions should also be taken? A. Keep all radio equipment ... capacitor insulation resistance. C. Ground the capacitor terminals. D. Check capacitor circuit polarity.

Last Answer : Answer: C

Complete maintenance of electrical motors should include periodic checks for machine _____________. A. vibration B. watertight integrity C. speed droop D. reactive power

Description : Complete maintenance of electrical motors should include periodic checks for machine _____________. A. vibration B. watertight integrity C. speed droop D. reactive power

Last Answer : Answer: A

Which of the listed procedures is the best way to tell if a motor has become overloaded? A. Measure the current flow and compare it with the motor full load current flow as shown on the nameplate. B. Feel the motor and judge by the temperature. C. Watch for telltale signs of smoke coming from the motor. D. Periodic opening of the O/L relay coil

Description : Which of the listed procedures is the best way to tell if a motor has become overloaded? A. Measure the current flow and compare it with the motor full load current flow as shown on the nameplate. ... Watch for telltale signs of smoke coming from the motor. D. Periodic opening of the O/L relay coil

Last Answer : Answer: A

The existing resistance of a conductor is dependent upon its length, cross-sectional area, _____________. A. temperature and insulation B. material and insulation C. resistive coefficient and material D. material and temperature

Description : The existing resistance of a conductor is dependent upon its length, cross-sectional area, _____________. A. temperature and insulation B. material and insulation C. resistive coefficient and material D. material and temperature

Last Answer : Answer: D

The 'E/P converter' shown in the illustration receives a _____________. EL-0096 A. steady pressure signal and produces a programmed electrical output B. variable electrical signal and produces a corresponding pressure output C. steady electrical signal and produces an inverse temperature correction D. variable pressure signal and produces a corresponding electrical output

Description : The 'E/P converter' shown in the illustration receives a _____________. EL-0096 A. steady pressure signal and produces a programmed electrical output B. variable electrical signal ... an inverse temperature correction D. variable pressure signal and produces a corresponding electrical output

Last Answer : Answer: B

The air gap provided in induction motors should be checked periodically with a feeler gage to detect an unequal air gap and _____________. A. decreased motor magnetizing current B. hysteresis loses C. increased power factor D. mechanical damage to the rotor

Description : The air gap provided in induction motors should be checked periodically with a feeler gage to detect an unequal air gap and _____________. A. decreased motor magnetizing current B. hysteresis loses C. increased power factor D. mechanical damage to the rotor

Last Answer : Answer: D

For power factor correction, synchronous motors operate at?

Last Answer : For power factor correction, synchronous motors operate at no-load and greatly over-excited fields.

The insulation resistance of electric equipment and machinery should be tested for the lowest normal insulation values _____________. A. immediately after shutting down the machine B. every time the brush rigging is adjusted C. immediately after starting up the machine D. every 30 days whether the machine is in use or not

Description : The insulation resistance of electric equipment and machinery should be tested for the lowest normal insulation values _____________. A. immediately after shutting down the machine B. every time the brush rigging is ... starting up the machine D. every 30 days whether the machine is in use or not

Last Answer : Answer: A

A current carrying conductor making an electrical contact with a wiring metal conduit is indicated by a _____________. A. low switchboard wattmeter reading B. reading of 1.0 on the power factor meter C. high switchboard voltmeter reading D. totally darkened switchboard ground-detecting light

Description : A current carrying conductor making an electrical contact with a wiring metal conduit is indicated by a _____________. A. low switchboard wattmeter reading B. reading of 1.0 on the power factor meter C. high switchboard voltmeter reading D. totally darkened switchboard ground-detecting light

Last Answer : Answer: D

The purpose of 'R6' in the winch circuit shown in the illustration is to _______________. EL-0102 A. maintain dry conditions within the winch brake box B. keep the series field current at a low value during 'fourth and fifth point lowering' C. act as the armature dynamic braking load to assist the winch in stopping D. limit the armature current during lowering operation with heavy loads

Description : The purpose of 'R6' in the winch circuit shown in the illustration is to _______________. EL-0102 A. maintain dry conditions within the winch brake box B. keep the series field current at ... to assist the winch in stopping D. limit the armature current during lowering operation with heavy loads

Last Answer : Answer: C

Electrical insulation is classed by the _____________. A. International Association of Electrical Manufacturers B. approximate operating voltage and current expected C. U.S. Coast Guard D. temperature stability of the manufacturing material(s)

Description : Electrical insulation is classed by the _____________. A. International Association of Electrical Manufacturers B. approximate operating voltage and current expected C. U.S. Coast Guard D. temperature stability of the manufacturing material(s)

Last Answer : Answer: D

Grounds occurring in electrical machinery as a result of insulation failure may result from _____________. A. deterioration through extended use B. excessive heat C. extended periods of vibration D. all of the above

Description : Grounds occurring in electrical machinery as a result of insulation failure may result from _____________. A. deterioration through extended use B. excessive heat C. extended periods of vibration D. all of the above

Last Answer : Answer: D

Low horsepower, polyphase, induction motors can be started with full voltage by means of _____________. A. compensator starters B. autotransformer starters C. across-the-line starters D. primary-resistor starters

Description : Low horsepower, polyphase, induction motors can be started with full voltage by means of _____________. A. compensator starters B. autotransformer starters C. across-the-line starters D. primary-resistor starters

Last Answer : Answer: C

Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor? A. Slow the motor down to low speed. B. Disconnect the motor from the power source. C. Secure all ventilation in the area. D. Preheat the insulation to assist in cleaning.

Description : Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor? A. Slow the motor down to low speed. B. Disconnect the motor from the power source. C. Secure all ventilation in the area. D. Preheat the insulation to assist in cleaning.

Last Answer : Answer: B

If air gap readings for an electical generating machine have changed significantly from the last reading, you should check _________. A. the bearings B. insulation readings and machine cleanliness C. the prime mover thrust bearing D. the field coil bolts for the proper torque values

Description : If air gap readings for an electical generating machine have changed significantly from the last reading, you should check _________. A. the bearings B. insulation readings and machine cleanliness C. the prime mover thrust bearing D. the field coil bolts for the proper torque values

Last Answer : Answer: A

When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates ____________. A. good insulation B. bad insulation C. high insulation power factor D. a high slot discharge factor

Description : When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates ____________. A. good insulation B. bad insulation C. high insulation power factor D. a high slot discharge factor

Last Answer : Answer: B

Shunt, series, and compound wound motors, are all DC motors designed to operate from _____________. A. constant potential, variable current DC sources B. variable potential, constant current DC sources C. variable potential, variable current DC sources D. constant potential, constant current DC sources

Description : Shunt, series, and compound wound motors, are all DC motors designed to operate from _____________. A. constant potential, variable current DC sources B. variable potential, constant current DC ... C. variable potential, variable current DC sources D. constant potential, constant current DC sources

Last Answer : Answer: A

Copper is often used as an electrical conductor because it _______________. A. has high resistance at low temperatures B. has a highly polished surface C. is able to pass current with little opposition D. holds insulation together well

Description : Copper is often used as an electrical conductor because it _______________. A. has high resistance at low temperatures B. has a highly polished surface C. is able to pass current with little opposition D. holds insulation together well

Last Answer : Answer: C

The 'reset' contacts of the master switch shown in the illustration provides the winch controller with ___________. EL-0102 A. low voltage release B. overload protection C. low voltage protection D. high power factor correction

Description : The 'reset' contacts of the master switch shown in the illustration provides the winch controller with ___________. EL-0102 A. low voltage release B. overload protection C. low voltage protection D. high power factor correction

Last Answer : Answer: C

As part of a routine maintenance program for deck machinery, you should ___________. A. inspect electrical wiring and pushbutton switches for evidence of corrosion or burned insulation B. disassemble pushbutton switches and drain water each week C. remove motor covers and ventilate as weather permits D. Check drum switch contact pressure every three months

Description : As part of a routine maintenance program for deck machinery, you should ___________. A. inspect electrical wiring and pushbutton switches for evidence of corrosion or burned insulation B. disassemble ... covers and ventilate as weather permits D. Check drum switch contact pressure every three months

Last Answer : Answer: A

On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. To check this insulation with the machine assembled you should use a____________. A. millivolt meter and a jumper B. ohmmeter C. megohm meter D. high potential tester

Description : On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. To check this insulation with the machine assembled you should use a____________. A. millivolt meter and a jumper B. ohmmeter C. megohm meter D. high potential tester

Last Answer : Answer: A

If deck machinery is expected to be idle for an extended period of time you should____________. A. have electrical safety gloves available in case of electrical shock before running B. perform a 'high pot' test to determine the condition of the insulation C. water wash the motor and controller to remove any salt that may interfere with smooth operation D. check run at regular intervals to inusre correct operation and to renew the internal coating of lubrication

Description : If deck machinery is expected to be idle for an extended period of time you should____________. A. have electrical safety gloves available in case of electrical shock before running B. perform ... run at regular intervals to inusre correct operation and to renew the internal coating of lubrication

Last Answer : Answer: D

On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. To check this insulation with the machine assembled you should use a____________. A. ohmmeter with the machine secured B. millivolt meter and a jumper with the machine running C. megohm meter with the machine running D. voltmeter and ampmeter with the machine running

Description : On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. To check this insulation with the machine assembled you should use a____________. A. ohmmeter with the ... C. megohm meter with the machine running D. voltmeter and ampmeter with the machine running

Last Answer : Answer: B

When a megohmmeter is being used to test insulation resistance, current leakage along the surface of the insulation is indicated by the megohmmeter pointer _____________. A. fluctuating around a constant resistance reading B. dipping towards 'zero', then rising slowly C. kicking slightly downscale as voltage is applied D. continually rising as the test voltage is applied

Description : When a megohmmeter is being used to test insulation resistance, current leakage along the surface of the insulation is indicated by the megohmmeter pointer _____________. A. fluctuating around a ... slightly downscale as voltage is applied D. continually rising as the test voltage is applied

Last Answer : Answer: C

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 _____________. A. dipping toward zero then raising slowly B. continually rising as test voltage is applied C. kicking slightly down scale as voltage is applied D. fluctuating around a constant resistance reading

Description : 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 _____________. A. dipping toward ... kicking slightly down scale as voltage is applied D. fluctuating around a constant resistance reading

Last Answer : Answer: C

Corresponding to Fig. (3), the loading on the portion AD of the beam will be (a) Uniformly distributed load (b) Uniformly varying load (c) Point loads (d) Cannot be said

Description : Corresponding to Fig. (3), the loading on the portion AD of the beam will be (a) Uniformly distributed load (b) Uniformly varying load (c) Point loads (d) Cannot be said

Last Answer : (a) Uniformly distributed load

When the bending moment is parabolic curve between two points, it indicates that there is (a) No loading between the two points (b) Point loads between the two points (c) U.D.L. between the two points (d) Uniformly varying load between the two points

Description : When the bending moment is parabolic curve between two points, it indicates that there is (a) No loading between the two points (b) Point loads between the two points (c) U.D.L. between the two points (d) Uniformly varying load between the two points

Last Answer : (c) U.D.L. between the two points

Routine A.C. motor maintenance should include periodic ______________. A. thermometer readings at normal loads to detect abnormal temperature rises B. inspection of the motor's internals for loose rotor bars or field poles C. bearing replacement each year using sealed units if available D. all of the above

Description : Routine A.C. motor maintenance should include periodic ______________. A. thermometer readings at normal loads to detect abnormal temperature rises B. inspection of the motor's internals for loose rotor bars ... C. bearing replacement each year using sealed units if available D. all of the above

Last Answer : Answer: A

When voltage and current developed in an AC circuit reach their peak values at the same time, the power factor is _____________. A. lagging B. leading C. maximum D. minimum

Description : When voltage and current developed in an AC circuit reach their peak values at the same time, the power factor is _____________. A. lagging B. leading C. maximum D. minimum

Last Answer : Answer: C

When the voltage and the current developed in an AC circuit reach their peak values at the same time, the power factor is considered to be _____________. A. lagging B. leading C. unity D. infinity

Description : When the voltage and the current developed in an AC circuit reach their peak values at the same time, the power factor is considered to be _____________. A. lagging B. leading C. unity D. infinity

Last Answer : Answer: C

To repair a small electrical motor that has been submerged in saltwater, you should _____________. A. wash it with fresh water and apply an external source of heat B. renew the windings C. send it ashore to an approved service facility D. rinse all electrical parts with a carbon tetrachloride cleaning solvent and then blow dry the motor with compressed air

Description : To repair a small electrical motor that has been submerged in saltwater, you should _____________. A. wash it with fresh water and apply an external source of heat B. renew the windings ... electrical parts with a carbon tetrachloride cleaning solvent and then blow dry the motor with compressed air

Last Answer : Answer: A

Describe the following energy conservation methods of electrical motor. i) By motor survey ii) By matching loads with motor rating

Description : Describe the following energy conservation methods of electrical motor. i) By motor survey ii) By matching loads with motor rating

Last Answer : Energy conservation methods of electrical motor:  1) By Motor Survey: Large industries have a massive population of LT motors. Load survey of LT motors can be taken-up methodically to ... -speed motors, eddy-current couplings, fluid couplings, and solid-state electronic variable speed drives.

The most common source of excitation for synchronous motors is a/an _____________. A. low voltage battery B. motor attenuator set C. DC exciter generator D. AC supply

Description : The most common source of excitation for synchronous motors is a/an _____________. A. low voltage battery B. motor attenuator set C. DC exciter generator D. AC supply

Last Answer : Answer: C

Unnecessary and frequent applications of varnish to the generator windings to repair defective insulation will result in ____________. A. heavy coatings of varnish interfering with heat dissipation B. deficient air gap clearance and eventual damage to the casing C. failure of the rectifier assembly D. a built-up of varnish without changing generator operation

Description : Unnecessary and frequent applications of varnish to the generator windings to repair defective insulation will result in ____________. A. heavy coatings of varnish interfering with heat dissipation B. ... of the rectifier assembly D. a built-up of varnish without changing generator operation

Last Answer : Answer: A

The need for insulation cleaning may be determined by _____. A. visual inspection for dirt accumulation B. high megger readings C. low operating temperature D. the time period since the last cleaning

Description : The need for insulation cleaning may be determined by _____. A. visual inspection for dirt accumulation B. high megger readings C. low operating temperature D. the time period since the last cleaning

Last Answer : Answer: A

Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding temperature with an accurate mercury thermometer C. periodic cleaning of the winding insulation with an approved solvent D. making sure that the units are close to bulkheads or corners to protect them from damage

Description : Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding ... . making sure that the units are close to bulkheads or corners to protect them from damage

Last Answer : Answer: A

In induction motors, the length of air gap in kept as small as mechanically possible is order to have (a) low power factor (b) high power factor (c) high over load capacity (d) any of the above

Description : In induction motors, the length of air gap in kept as small as mechanically possible is order to have (a) low power factor (b) high power factor (c) high over load capacity (d) any of the above

Last Answer : (b) high power factor