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

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
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Answer: A
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Related questions

Air gap readings should be taken periodicly on electrical generation equipment to __________. A. determine the amount of varnish that can be applied to correct insulation problems B. determine the condition of the bearings C. provide for the correct proper tightening of the field coil bolts and correct lateral adjustment of the field coils D. increase machine efficiency

Description : Air gap readings should be taken periodicly on electrical generation equipment to __________. A. determine the amount of varnish that can be applied to correct insulation problems B. determine the ... field coil bolts and correct lateral adjustment of the field coils D. increase machine efficiency

Last Answer : Answer: B

If the bearings of an electrical generator are failing more frequently than expected and the lubricating oil is sludging then you should ______________. A. check the connections to the output leads B. check the bearing insulating block on one end of the unit C. replace the bearing with a sealed roller type D. replace the thrust bearing of the prime mover

Description : If the bearings of an electrical generator are failing more frequently than expected and the lubricating oil is sludging then you should ______________. A. check the connections to the output leads B. ... replace the bearing with a sealed roller type D. replace the thrust bearing of the prime mover

Last Answer : Answer: B

Air gap readings should be taken on electrical generation machinery periodicly to _________. I. determine the need for cleaning II. check the condition of the bearings A. I only B. II only C. both I and II D. neither I or II

Description : Air gap readings should be taken on electrical generation machinery periodicly to _________. I. determine the need for cleaning II. check the condition of the bearings A. I only B. II only C. both I and II D. neither I or II

Last Answer : Answer: B

Air gap readings for electrical generating equipment should be taken periodicly. This is to _______. I. determine the condition of the bearings II. prevent damage to the rotor and stator A. I only B. II only C. both I and II D. neither I or II

Description : Air gap readings for electrical generating equipment should be taken periodicly. This is to _______. I. determine the condition of the bearings II. prevent damage to the rotor and stator A. I only B. II only C. both I and II D. neither I or II

Last Answer : Answer: C

The following air gap readings were obtained from a horizontally mounted, bilge pump, induction motor, equipped with sleeve bearings: FWD END-AFT END, Top .045 - .049, Right Side .045 - .047, Left Side .045 - .047, Bottom .045 - .041 Which of the f A. both the aft and foward bearings should be replaced. B. Shims should be removed from the aft bearing. C. The forward bearing should be lowered. D. The aft bearing should be lowered.

Description : The following air gap readings were obtained from a horizontally mounted, bilge pump, induction motor, equipped with sleeve bearings: FWD END-AFT END, Top .045 - .049, Right Side .045 - .047, Left ... the aft bearing. C. The forward bearing should be lowered. D. The aft bearing should be lowered.

Last Answer : Answer: A

The following air gap readings were obtained from a horizontally mounted, bilge pump, induction motor, equipped with sleeve bearings: FWD END -AFT END, Top .045 - .049 , Right Side .045 - .047, Left Side .045 - .047 , Bottom .045 - .041 Which of the fo A. The aft bearing should be realigned or replaced. B. Shims should be removed from the aft bearing. C. The forward bearing should be lowered. D. The aft bearing should be lowered.

Description : The following air gap readings were obtained from a horizontally mounted, bilge pump, induction motor, equipped with sleeve bearings: FWD END -AFT END, Top .045 - .049 , Right Side .045 - .047, Left ... the aft bearing. C. The forward bearing should be lowered. D. The aft bearing should be lowered.

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

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

Air gap readings should be taken on electrical generation equipment periodicly to ________. I. check machine effeciency II. determine the need for cleaning A. I only B. II only C. both I and II D. neither I or II

Description : Air gap readings should be taken on electrical generation equipment periodicly to ________. I. check machine effeciency II. determine the need for cleaning A. I only B. II only C. both I and II D. neither I or II

Last Answer : Answer: D

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

If the energy input is significantly reduced to the prime mover of one shipboard alternator operating in parallel with others, that alternator will _____________. A. continue to operate at no load B. lose its load and overspeed C. begin to motorize and then trip out D. slow down and operate at reduced load

Description : If the energy input is significantly reduced to the prime mover of one shipboard alternator operating in parallel with others, that alternator will _____________. A. continue to operate at no load B. lose ... overspeed C. begin to motorize and then trip out D. slow down and operate at reduced load

Last Answer : Answer: C

The voltage output of an AC generator is accurately controlled by _____________. A. changing the sensitivity of the prime mover to large changes in voltage B. varying the reluctance of the air gap C. varying the DC exciter voltage D. shorting out part of the armature windings

Description : The voltage output of an AC generator is accurately controlled by _____________. A. changing the sensitivity of the prime mover to large changes in voltage B. varying the reluctance of the air gap C. varying the DC exciter voltage D. shorting out part of the armature windings

Last Answer : Answer: C

On electrical generators one of the bearings is isolated from the bedplate. This insulating block should not be painted and must be kept clean to ___________. A. protect operating personnel from shock B. create an isolated ground for the instrumentation C. allow for the expansion of the generator away from the prime mover as it warms up D. eliminate shaft currents to prevent damaging the bearings

Description : On electrical generators one of the bearings is isolated from the bedplate. This insulating block should not be painted and must be kept clean to ___________. A. protect operating personnel from shock ... the prime mover as it warms up D. eliminate shaft currents to prevent damaging the bearings

Last Answer : Answer: D

In the illustrated motor, roller bearings are used because __________. EL-0001 A. of their ability to absorb moderate thrust loads B. they electrically insulate the rotor from the frame reducing cross-currents C. the shafting and end bells do not require as close a tolerance to properly fit this type of bearing D. the clearance between the rotor and stator is generally as close as mechanical tolerance will permit

Description : In the illustrated motor, roller bearings are used because __________. EL-0001 A. of their ability to absorb moderate thrust loads B. they electrically insulate the rotor from the frame reducing ... clearance between the rotor and stator is generally as close as mechanical tolerance will permit

Last Answer : Answer: D

The rotor slots of a repulsion-type motor are generally skewed (placed nonparallel to the rotor axis) to _________. A. produce a constant starting torque B. permit a greater air gap with the starter C. permit a smaller air gap with the starter D. reduce eddy current losses

Description : The rotor slots of a repulsion-type motor are generally skewed (placed nonparallel to the rotor axis) to _________. A. produce a constant starting torque B. permit a greater air gap with the starter C. permit a smaller air gap with the starter D. reduce eddy current losses

Last Answer : Answer: A

What happens if speed of prime mover is changed keeping excitation of alternator constant?

Description : What happens if speed of prime mover is changed keeping excitation of alternator constant?

Last Answer : If speed of prime mover is changed, the speed of alternator also changes hence frequency also changes. The frequency increase with increase in steam input and hence speed and vise versa.

What happens if excitation of alternator is changed keeping speed of prime mover constant?

Description : What happens if excitation of alternator is changed keeping speed of prime mover constant?

Last Answer : The emf induced will be changed and hence terminal voltage will also change. The terminal voltage will increase with increase in excitation and vise versa.

In the illustration, the contacts between terminals 26 and 27 should be closed when _________. EL-0046 A. using one generator in isochronous mode only B. using two or more generators in parallel only C. the prime mover speed is to remain constant through varying loads in parallel or single operation D. the circuit breaker is closed for that generator

Description : In the illustration, the contacts between terminals 26 and 27 should be closed when _________. EL-0046 A. using one generator in isochronous mode only B. using two or more generators in ... through varying loads in parallel or single operation D. the circuit breaker is closed for that generator

Last Answer : Answer: C

A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an equal or lower value B. low or zero voltage reading, while the other coils will have higher readings C. fluctuating voltmeter reading, while the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating

Description : A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an ... the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating

Last Answer : Answer: B

In an induction machine, if the air gap increased a) Speed will be reduced b) Efficiency will be improved c) Power factor will be lowered d) Breakdown torque will be reduced

Description : In an induction machine, if the air gap increased a) Speed will be reduced b) Efficiency will be improved c) Power factor will be lowered d) Breakdown torque will be reduced

Last Answer : Ans: Power factor will be lowered

Which of the following cannot tolerate misalignment? (a) Angular contact bearing (b) Cylinder roller bearing (c) Thrust ball bearings (d) All of the listed

Description : Which of the following cannot tolerate misalignment? (a) Angular contact bearing (b) Cylinder roller bearing (c) Thrust ball bearings (d) All of the listed

Last Answer : (d) All of the listed

Which of the bearings given below SHOULD NOT be subjected to a thrust load? (a) Deep groove ball bearing (b) Angular contact ball bearing (c) Cylindrical (straight) roller bearing (d) Single row tapered roller bearing

Description : Which of the bearings given below SHOULD NOT be subjected to a thrust load? (a) Deep groove ball bearing (b) Angular contact ball bearing (c) Cylindrical (straight) roller bearing (d) Single row tapered roller bearing

Last Answer : (c) Cylindrical (straight) roller bearing

Match List -I (Bearings) with List-II (Applications) and select the using the codes given below the lists: [IAS-1998] List –I List-II A. Journal bearing 1. Electric motors B. Thrust bearing 2. Watches C. Conical pivot bearing 3. Marine engines D. Ball bearing 4. Swivelling chairs A B C D A B C D (a) 3 4 1 2 (b) 4 2 1 3 (c) 3 4 2 1 (d) 4 2 3 1

Description : Match List -I (Bearings) with List-II (Applications) and select the using the codes given below the lists: [IAS-1998] List -I List-II A. Journal bearing 1. Electric motors B. Thrust bearing 2. Watches C. Conical pivot bearing 3. Marine ... D (a) 3 4 1 2 (b) 4 2 1 3 (c) 3 4 2 1 (d) 4 2 3 1

Last Answer : (c) 3 4 2 1

Match List I with List II and select the : [IES-2002] List I (Bearings) List II (Load type) A. Hydrodynamic Journal bearing 1. High radial and thrust load combined B. Rectangular Hydrostatic bearing 2. Radial load only C. Taper Roller bearing 3. Thrust load only D. Angular contact ball bearing 4. Medium to low radial and thrust combined A B C D A B C D (a) 2 3 1 4 (b) 4 1 3 2 (c) 2 1 3 4 (d) 4 3 1 2

Description : Match List I with List II and select the : [IES-2002] List I (Bearings) List II (Load type) A. Hydrodynamic Journal bearing 1. High radial and thrust load combined B. Rectangular Hydrostatic bearing 2. Radial load only C. Taper Roller ... (a) 2 3 1 4 (b) 4 1 3 2 (c) 2 1 3 4 (d) 4 3 1 2

Last Answer : (a) 2 3 1 4

Which of the following cannot tolerate misalignment? a) Angular contact bearing b) Cylinder roller bearing c) Thrust ball bearings d) All of the listed

Description : Which of the following cannot tolerate misalignment? a) Angular contact bearing b) Cylinder roller bearing c) Thrust ball bearings d) All of the listed

Last Answer : d) All of the listed

The bearings which resist radial loads is known as a) Ball bearing b) bush bearing c) thrust bearing d) journal bearing

Description : The bearings which resist radial loads is known as a) Ball bearing b) bush bearing c) thrust bearing d) journal bearing

Last Answer : d) journal bearing

The failure of ball bearings used in electric motors can result from _____________. A. failure to clean the bearing before repacking B. failure to maintain proper alignment C. excess lubrication forcing the bearing full of grease and eliminating all areas of expansion D. all of the above

Description : The failure of ball bearings used in electric motors can result from _____________. A. failure to clean the bearing before repacking B. failure to maintain proper alignment C. excess lubrication forcing the bearing full of grease and eliminating all areas of expansion D. all of the above

Last Answer : Answer: D

During its operation, loud buzzing and resultant welding of contacts of a magnetic relay may be caused by __________. A. overheating of the contactor coil B. low voltage on the operating coil C. low insulation resistance to ground D. lubrication of the contact bearing points

Description : During its operation, loud buzzing and resultant welding of contacts of a magnetic relay may be caused by __________. A. overheating of the contactor coil B. low voltage on the operating coil C. low insulation resistance to ground D. lubrication of the contact bearing points

Last Answer : Answer: B

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

Which of the methods listed is used to start a AC generator turning? A. Residual magnetism remaining in the field poles. B. Residual magnetism remaining in the field coils. C. Residual magnetism remaining in the armature. D. Rotation by a mechanical prime mover.

Description : Which of the methods listed is used to start a AC generator turning? A. Residual magnetism remaining in the field poles. B. Residual magnetism remaining in the field coils. C. Residual magnetism remaining in the armature. D. Rotation by a mechanical prime mover.

Last Answer : Answer: D

The voltage developed by an AC generator is controlled by varying the ____________. A. speed of the prime mover B. AC excitation to the field C. DC excitation to the field D. DC excitation of the voltage regulator

Description : The voltage developed by an AC generator is controlled by varying the ____________. A. speed of the prime mover B. AC excitation to the field C. DC excitation to the field D. DC excitation of the voltage regulator

Last Answer : Answer: C

Automatic voltage regulators provided on switchboards function to _____________. A. regulate the AC load on the generator B. protect the switchboard from high voltage C. govern prime mover speed to control voltage D. vary the field excitation to the generators

Description : Automatic voltage regulators provided on switchboards function to _____________. A. regulate the AC load on the generator B. protect the switchboard from high voltage C. govern prime mover speed to control voltage D. vary the field excitation to the generators

Last Answer : Answer: D

The standard method of controlling the output voltage of a 440 volt, 60 Hz, AC generator is accomplished by adjusting the ____________. A. prime mover speed droop B. number of poles C. alternator field excitation D. load on the alternator

Description : The standard method of controlling the output voltage of a 440 volt, 60 Hz, AC generator is accomplished by adjusting the ____________. A. prime mover speed droop B. number of poles C. alternator field excitation D. load on the alternator

Last Answer : Answer: C

The power factor of an AC generator operating singularly is determined by the __________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage

Description : The power factor of an AC generator operating singularly is determined by the __________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage

Last Answer : Answer: A

The power factor at which a paralleled AC generator operates is usually adjusted by the _____________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage

Description : The power factor at which a paralleled AC generator operates is usually adjusted by the _____________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage

Last Answer : Answer: C

To increase the frequency of an operating AC generator, you should ____________. A. increase the field excitation B. decrease the field excitation C. increase the number of magnetic poles D. increase the speed of the prime mover

Description : To increase the frequency of an operating AC generator, you should ____________. A. increase the field excitation B. decrease the field excitation C. increase the number of magnetic poles D. increase the speed of the prime mover

Last Answer : Answer: D

The frequency of an AC generator is adjusted by means of the ____________. A. main alternator field rheostat B. exciter field rheostat C. prime mover governor control D. equalizing reactor

Description : The frequency of an AC generator is adjusted by means of the ____________. A. main alternator field rheostat B. exciter field rheostat C. prime mover governor control D. equalizing reactor

Last Answer : Answer: C

As load is added to an AC generator provided with constant field excitation, the prime mover slows down with the effect of ____________. A. lowering frequency and lowering generated voltage B. increasing frequency and increasing generated voltage C. increasing frequency and lowering generated voltage D. lowering frequency and increasing generated voltage

Description : As load is added to an AC generator provided with constant field excitation, the prime mover slows down with the effect of ____________. A. lowering frequency and lowering generated ... C. increasing frequency and lowering generated voltage D. lowering frequency and increasing generated voltage

Last Answer : Answer: A

The division of the kilowatt load between two AC generators operating in parallel is controlled by the settings and characteristics of the _____________. A. voltage regulators B. field rheostats C. reverse power relays D. prime mover governors

Description : The division of the kilowatt load between two AC generators operating in parallel is controlled by the settings and characteristics of the _____________. A. voltage regulators B. field rheostats C. reverse power relays D. prime mover governors

Last Answer : Answer: D

In an AC synchronous motor electric propulsion plant, propeller speed is controlled by varying the _____________. A. prime mover speed B. electric coupling field strength C. number of energized main motor poles D. propulsion generator field strength

Description : In an AC synchronous motor electric propulsion plant, propeller speed is controlled by varying the _____________. A. prime mover speed B. electric coupling field strength C. number of energized main motor poles D. propulsion generator field strength

Last Answer : Answer: A

When you check the specific gravity of the battery electrolyte with a hydrometer, it should be kept in mind that ____________. A. the battery is fully charged when the indicator floats low in the electrolyte B. any water that has been previously added to the cells will dilute the solution and give a false reading C. a hydrometer reading is inaccurate if taken immediately after water is added to the cell D. temperature has no effect on hydrometer readings

Description : When you check the specific gravity of the battery electrolyte with a hydrometer, it should be kept in mind that ____________. A. the battery is fully charged when the indicator floats low in ... taken immediately after water is added to the cell D. temperature has no effect on hydrometer readings

Last Answer : Answer: C

Air gap readings should be periodicly taken for electrical generation equipment. The best tool to use to take these measurements is a ___________. A. cloth (non-metalic) tape measure B. dial indicator C. inside micrometer D. tapered, long blade, feeler gage

Description : Air gap readings should be periodicly taken for electrical generation equipment. The best tool to use to take these measurements is a ___________. A. cloth (non-metalic) tape measure B. dial indicator C. inside micrometer D. tapered, long blade, feeler gage

Last Answer : Answer: D

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 troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by _______________. A. a resistance reading of 'infinity' on an ohmmeter B. charred insulation and/or a blown control fuse C. a reading of 'zero' on a megger from one of the coil's leads to ground D. a higher-than-normal voltage reading across the winding

Description : When troubleshooting motor controllers, a shorted relay or contactor coil is often indicated by _______________. A. a resistance reading of 'infinity' on an ohmmeter B. charred insulation and/or a blown ... of the coil's leads to ground D. a higher-than-normal voltage reading across the winding

Last Answer : Answer: B

The air gap in an induction motor should be periodically checked with a feeler gage to prevent possible ___________. A. rotor contact with the stator B. axial misalignment of the rotor C. damage to the motor bearings D. electrical damage to the bearings

Description : The air gap in an induction motor should be periodically checked with a feeler gage to prevent possible ___________. A. rotor contact with the stator B. axial misalignment of the rotor C. damage to the motor bearings D. electrical damage to the bearings

Last Answer : Answer: A

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

Description : 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 ... wasted if full loading is not utilized D. power factor correction methods are load dependent

Last Answer : Answer: B

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

In preparing to take insulation resistance readings on a main generator, the windings should be grounded for about 15 minutes prior to the test to _____________. A. allow accurate zeroing of the meter B. help the windings to cool to ambient temperature C. release any residual capacitive charge from the windings D. help the windings to cool to the same temperature as the ground test connection

Description : In preparing to take insulation resistance readings on a main generator, the windings should be grounded for about 15 minutes prior to the test to _____________. A. allow accurate zeroing of the meter ... the windings D. help the windings to cool to the same temperature as the ground test connection

Last Answer : Answer: C