A testing device called a 'growler' is being used to locate a shorted coil in the stator of an AC electrical machine. When the 'feeler' is moved over a slot containing the shorted coil _____________. A. a loud growling noise will be heard B. any vibration within the feeler will cease C. the meter needle will be deflected to zero D. the meter needle will be deflected to full-scale

A testing device called a 'growler' is being used to locate a shorted coil in the stator of an AC electrical machine. When the 'feeler' is moved over a slot containing the shorted coil _____________. A. a loud growling noise will be heard B. any vibration within the feeler will cease C. the meter needle will be deflected to zero D. the meter needle will be deflected to full-scale
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Answer: A
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Related questions

Which of the following methods should be used to test for an 'open' coil in an AC motor stator? A. Test with an ohmmeter, one test lead on the shaft, and the other test lead to the stator leads. B. Test with an ohmmeter with the test leads between the stator leads. C. Use a growler, listening for noise and vibration to diminish when over an open coil. D. Use a growler, listening for noise and vibration to increase when over an open coil.

Description : Which of the following methods should be used to test for an 'open' coil in an AC motor stator? A. Test with an ohmmeter, one test lead on the shaft, and the other test lead to the stator leads ... an open coil. D. Use a growler, listening for noise and vibration to increase when over an open coil.

Last Answer : Answer: B

When troubleshooting AC motors, a portable growler can be used for locating ____________. A. open field coils B. grounded field coils C. grounded stator coils D. shorted stator coils

Description : When troubleshooting AC motors, a portable growler can be used for locating ____________. A. open field coils B. grounded field coils C. grounded stator coils D. shorted stator coils

Last Answer : Answer: D

When a megohmmeter is being used on a alternating current machine, the meter pointer will dip toward 'zero' and then gradually rise to the true resistance value if the motor insulation is _____________. A. grounded B. good C. shorted D. dirty

Description : When a megohmmeter is being used on a alternating current machine, the meter pointer will dip toward 'zero' and then gradually rise to the true resistance value if the motor insulation is _____________. A. grounded B. good C. shorted D. dirty

Last Answer : Answer: B

A short in the shunt field of a DC motor is best located by _____________. A. visual inspection of the commutator B. applying AC voltage to each field coil and measuring the voltage drop across each field coil C. using a growler and hacksaw blade D. isolating each coil from the others and using a megohmmeter

Description : A short in the shunt field of a DC motor is best located by _____________. A. visual inspection of the commutator B. applying AC voltage to each field coil and measuring the voltage drop across ... using a growler and hacksaw blade D. isolating each coil from the others and using a megohmmeter

Last Answer : Answer: B

A loud buzzing noise in an AC controller is probably caused by _____________. A. poor contact with the overload relay B. an incorrectly sized heater C. a broken shading coil D. abnormal starting current

Description : A loud buzzing noise in an AC controller is probably caused by _____________. A. poor contact with the overload relay B. an incorrectly sized heater C. a broken shading coil D. abnormal starting current

Last Answer : Answer: C

A capacitor is to be tested with a megohmmeter. If the meter is connected to a shorted capacitor, the meter pointer should _____________. A. immediately swing to the maximum resistance value B. deflect to zero and remain at that position C. swing to a high reading and gradually decrease D. swing to zero then gradually increase with slight pointer movements down scale

Description : A capacitor is to be tested with a megohmmeter. If the meter is connected to a shorted capacitor, the meter pointer should _____________. A. immediately swing to the maximum resistance value ... and gradually decrease D. swing to zero then gradually increase with slight pointer movements down scale

Last Answer : Answer: B

A capacitor can be tested using a megohmmeter or an ohmmeter. If the meter is connected to a shorted capacitor, the meter pointer should _____________. A. immediately swing to the maximum resistance value for the capacitor B. first swing quickly to 'zero', then gradually move up the scale as the capacitor charges C. immediately deflect to and remain at zero D. immediately swing to a high reading and then gradually decrease

Description : A capacitor can be tested using a megohmmeter or an ohmmeter. If the meter is connected to a shorted capacitor, the meter pointer should _____________. A. immediately swing to the maximum resistance ... deflect to and remain at zero D. immediately swing to a high reading and then gradually decrease

Last Answer : Answer: C

A shading coil used in an AC magnetic controller, functions to _____________. A. reduce vibration and noise in the contactor B. prevent flux buildup in the operating coil C. eliminate arcing when the contacts close D. energize the operating coil and 'pull in' the contacts

Description : A shading coil used in an AC magnetic controller, functions to _____________. A. reduce vibration and noise in the contactor B. prevent flux buildup in the operating coil C. eliminate arcing when the contacts close D. energize the operating coil and 'pull in' the contacts

Last Answer : Answer: A

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

Prior to using an analog type ohmmeter, the leads are purposely shorted together. Which of the following actions should be taken if, when adjusting to 'zero' ohms, the indicating needle can not be returned to 'zero' on the scale? A. The lead clips should be replaced. B. The batteries should be replaced. C. The test reading should be added to each final reading. D. The test reading should be subtracted from each final reading.

Description : Prior to using an analog type ohmmeter, the leads are purposely shorted together. Which of the following actions should be taken if, when adjusting to 'zero' ohms, the indicating needle can not be ... be added to each final reading. D. The test reading should be subtracted from each final reading.

Last Answer : Answer: B

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

Aboard ship, a grounded field coil in an AC motor can be determined by using a _________________. A. portable growler B. galvanometer C. visual inspection D. megohmmeter

Description : Aboard ship, a grounded field coil in an AC motor can be determined by using a _________________. A. portable growler B. galvanometer C. visual inspection D. megohmmeter

Last Answer : Answer: D

A 4-pole, 3-phase, double-layer winding is housed in a 36-slot stator for an ac machine with

Description : A 4-pole, 3-phase, double-layer winding is housed in a 36-slot stator for an ac machine with 60o phase spread. Coil span is 7 short pitches. Number of slots in which top and bottom layers belong to different phases is  (A) 24 (B) 18 (C) 12 (D) 0

Last Answer : A 4-pole, 3-phase, double-layer winding is housed in a 36-slot stator for an ac machine with 60o phase spread. Coil span is 7 short pitches. Number of slots in which top and bottom layers belong to different phases is 24 

A shorted armature coil in a DC motor can be detected by _____________. A. sparking at the brushes B. shiny armature coil C. worn grooves in the armature D. undercut mica

Description : A shorted armature coil in a DC motor can be detected by _____________. A. sparking at the brushes B. shiny armature coil C. worn grooves in the armature D. undercut mica

Last Answer : Answer: A

A megohmmeter can be used to test for _____________. A. an open field coil B. a shorted field pole C. undercut mica D. reversed polarity

Description : A megohmmeter can be used to test for _____________. A. an open field coil B. a shorted field pole C. undercut mica D. reversed polarity

Last Answer : Answer: A

The leads from a megohmmeter are attached to the leads of an AC motor field coil. A reading of infinity is obtained indicating a/an ____________. A. open field coil B. shorted field coil C. grounded field coil D. shunted field coil

Description : The leads from a megohmmeter are attached to the leads of an AC motor field coil. A reading of infinity is obtained indicating a/an ____________. A. open field coil B. shorted field coil C. grounded field coil D. shunted field coil

Last Answer : Answer: A

Excessive humming of AC contactors may be caused by ______________. A. burnt arc shields B. shorted armature coils C. a broken shading coil D. high voltage

Description : Excessive humming of AC contactors may be caused by ______________. A. burnt arc shields B. shorted armature coils C. a broken shading coil D. high voltage

Last Answer : Answer: C

While testing a semi-conductor diode with an ohmmeter, both the forward and reverse readings are almost in the infinity range. This would indicate that the unit is _____________. A. good B. open C. grounded D. shorted

Description : While testing a semi-conductor diode with an ohmmeter, both the forward and reverse readings are almost in the infinity range. This would indicate that the unit is _____________. A. good B. open C. grounded D. shorted

Last Answer : Answer: B

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

One diode of a full-wave rectifier has burned out in a shorted condition. Therefore, the output will be ____________. A. zero B. a rectified half-wave C. a rectified full-wave D. equal to the AC input

Description : One diode of a full-wave rectifier has burned out in a shorted condition. Therefore, the output will be ____________. A. zero B. a rectified half-wave C. a rectified full-wave D. equal to the AC input

Last Answer : Answer: D

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 rotation of a three-phase induction motor can be reversed by _____________. A. interchanging any two of the three line leads to the stator B. disconnecting one of the three line leads to the stator C. switching the shunt field coil leads D. permanently disconnecting any two of the three line leads to the stator

Description : The rotation of a three-phase induction motor can be reversed by _____________. A. interchanging any two of the three line leads to the stator B. disconnecting one of the three line leads to the ... the shunt field coil leads D. permanently disconnecting any two of the three line leads to the stator

Last Answer : Answer: A

To determine if a stator coil is grounded, you should use a/an _____________. A. ammeter B. ground detection lamp C. magneto D. megger

Description : To determine if a stator coil is grounded, you should use a/an _____________. A. ammeter B. ground detection lamp C. magneto D. megger

Last Answer : Answer: D

Which of the following statements regarding the use of a current measuring instrument is correct? A. It must be connected in series with the circuit. B. You should always start with the lowest range until a suitable reading is obtained. C. The indicating needle is deflected from left to right regardless of polarity. D. An external shunt is generally utilized where current is less than 10 amperes.

Description : Which of the following statements regarding the use of a current measuring instrument is correct? A. It must be connected in series with the circuit. B. You should always start with the lowest range ... of polarity. D. An external shunt is generally utilized where current is less than 10 amperes.

Last Answer : Answer: A

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

The electrical device shown in the illustration is a/an _____________. EL-0077 A. operating coil B. indicating lamp C. motor armature D. potentiometer

Description : The electrical device shown in the illustration is a/an _____________. EL-0077 A. operating coil B. indicating lamp C. motor armature D. potentiometer

Last Answer : Answer: D

Which of the instruments listed could be use to locate a grounded field coil in a synchronous motor? A. Ammeter B. Voltmeter C. Megohmmeter D. Frequency meter

Description : Which of the instruments listed could be use to locate a grounded field coil in a synchronous motor? A. Ammeter B. Voltmeter C. Megohmmeter D. Frequency meter

Last Answer : Answer: C

Which of the listed instruments can be best used to locate a grounded field coil in a synchronous motor? A. Frequency meter B. Megohmmeter C. Voltmeter D. Multimeter

Description : Which of the listed instruments can be best used to locate a grounded field coil in a synchronous motor? A. Frequency meter B. Megohmmeter C. Voltmeter D. Multimeter

Last Answer : Answer: B

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

The air gap in an induction motor should be checked periodically with a feeler gage to detect ____________. A. rotor contact with the laminations B. changes in armature magnetic strength C. excessive bearing wear D. electrical damage to the rotor

Description : The air gap in an induction motor should be checked periodically with a feeler gage to detect ____________. A. rotor contact with the laminations B. changes in armature magnetic strength C. excessive bearing wear D. electrical damage to the rotor

Last Answer : Answer: C

A three-phase, squirrel cage, induction motor will run hot due to a/an ______________. A. improper brush position B. reversed commutating pole C. shorted stator D. high power factor

Description : A three-phase, squirrel cage, induction motor will run hot due to a/an ______________. A. improper brush position B. reversed commutating pole C. shorted stator D. high power factor

Last Answer : Answer: C

Before measuring an unknown resistance with an ohmmeter, you should _____________. A. adjust the meter's pointer to mid-scale B. short the test leads and calibrate the meter reading to 'zero' C. change the meter's batteries D. center the meter's pointer at infinity

Description : Before measuring an unknown resistance with an ohmmeter, you should _____________. A. adjust the meter's pointer to mid-scale B. short the test leads and calibrate the meter reading to 'zero' C. change the meter's batteries D. center the meter's pointer at infinity

Last Answer : Answer: B

Type of power-line frequency meter device utilizing a principle of balancing an indicator needle at center of a scale using magnetic fields opposing each other.

Description : Type of power-line frequency meter device utilizing a principle of balancing an indicator needle at center of a scale using magnetic fields opposing each other.

Last Answer : magnetic type

If a DC motor runs faster than designed, with all other conditions being normal, the possible cause could be a/an ______________. A. shorted shunt field coil B. open armature coil C. reversed commutating pole D. overload

Description : If a DC motor runs faster than designed, with all other conditions being normal, the possible cause could be a/an ______________. A. shorted shunt field coil B. open armature coil C. reversed commutating pole D. overload

Last Answer : Answer: A

A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an _____________. A. rotor B. stator C. exciter D. armature

Description : A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an _____________. A. rotor B. stator C. exciter D. armature

Last Answer : Answer: C

The amount of voltage induced in the windings of an AC generator depends mainly on _____________. A. the number of field poles energized B. the speed at which the stator windings rotate through the magnetic field C. the strength of the magnetic field D. all of the above

Description : The amount of voltage induced in the windings of an AC generator depends mainly on _____________. A. the number of field poles energized B. the speed at which the stator windings rotate through the magnetic field C. the strength of the magnetic field D. all of the above

Last Answer : Answer: C

A loud buzzing noise at the contacts of a magnetic controller could indicate _____________. A. weak contact spring pressure B. misalignment of the magnet faces C. excessive line current D. mechanical binding

Description : A loud buzzing noise at the contacts of a magnetic controller could indicate _____________. A. weak contact spring pressure B. misalignment of the magnet faces C. excessive line current D. mechanical binding

Last Answer : Answer: B

When using a megohmmeter to test insulation, good insulation will be indicated by _____________. A. slight kicks of the needle down scale B. a downward dip followed by a gradual climb to the true resistance value C. a gradual rise in the pointer reading at the outset D. the initial dip of the pointer

Description : When using a megohmmeter to test insulation, good insulation will be indicated by _____________. A. slight kicks of the needle down scale B. a downward dip followed by a gradual climb to the true resistance ... C. a gradual rise in the pointer reading at the outset D. the initial dip of the pointer

Last Answer : Answer: B

The illustrated motor fails to start and gives a loud hum when the start button is depressed, your first action should be to __________. EL-0007 A. disassemble the motor to fix the centrifical switch so the start windings will be energized B. push the stop button to deenergize the 'M' coil C. reset the thermal overload D. hold the 'M' contactor closed by hand while wearing electrical safety gloves to get motor started

Description : The illustrated motor fails to start and gives a loud hum when the start button is depressed, your first action should be to __________. EL-0007 A. disassemble the motor to fix the centrifical ... D. hold the 'M' contactor closed by hand while wearing electrical safety gloves to get motor started

Last Answer : Answer: B

Shading coils are installed on AC full-voltage starters to _____________. A. eliminate contact chatter B. dissipate opening contact arcs C. delay current build up in the holding coil D. protect the motor windings from momentary starting current overload

Description : Shading coils are installed on AC full-voltage starters to _____________. A. eliminate contact chatter B. dissipate opening contact arcs C. delay current build up in the holding coil D. protect the motor windings from momentary starting current overload

Last Answer : Answer: A

The speed of a squirrel-cage motor is usually changed by _____________. A. varying the frequency to the machine B. adding resistance in series with the stator windings C. adding resistance in parallel with the stator windings D. changing the number of connected poles in the stator

Description : The speed of a squirrel-cage motor is usually changed by _____________. A. varying the frequency to the machine B. adding resistance in series with the stator windings C. adding resistance in parallel with the stator windings D. changing the number of connected poles in the stator

Last Answer : Answer: D

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

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

Voltage generated by most AC generators is fed from the machine to the bus by means of ____________. A. brushes on a commutator B. brushes on slip rings C. slip rings on a commutator D. direct connections from the stator

Description : Voltage generated by most AC generators is fed from the machine to the bus by means of ____________. A. brushes on a commutator B. brushes on slip rings C. slip rings on a commutator D. direct connections from the stator

Last Answer : Answer: D

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

The main difference between a motor control circuit containing low voltage protection and low voltage release is that the latter contains _____________. A. a magnetic operating coil B. normally open line contacts C. thermal-overload protection D. a momentary-contact start button

Description : The main difference between a motor control circuit containing low voltage protection and low voltage release is that the latter contains _____________. A. a magnetic operating coil B. normally open line contacts C. thermal-overload protection D. a momentary-contact start button

Last Answer : Answer: D

A device which converts chemical energy into electrical energy is called -----? A. motor B. generator C. moving-coil meter D. battery (Answer)

Description : A device which converts chemical energy into electrical energy is called -----? A. motor B. generator C. moving-coil meter D. battery (Answer)

Last Answer : D. battery (Answer)

When a resistor is used as a shunt and is connected in parallel with a meter movement coil, it will provide _____________. A. a measurement of circuit resistance B. an increased accuracy of approximately 1.5 percent C. an extended meter range D. none of the above

Description : When a resistor is used as a shunt and is connected in parallel with a meter movement coil, it will provide _____________. A. a measurement of circuit resistance B. an increased accuracy of approximately 1.5 percent C. an extended meter range D. none of the above

Last Answer : Answer: C

The basic meter movement responds to the flow of current through its coil. Therefore, this meter movement may be used as a/an _____________. A. voltmeter by placing a resistance in parallel with the coil B. ohmmeter by placing another meter movement in parallel with the coil C. wattmeter by placing a battery in parallel with the coil D. ammeter by placing a low resistance in parallel with the coil

Description : The basic meter movement responds to the flow of current through its coil. Therefore, this meter movement may be used as a/an _____________. A. voltmeter by placing a resistance in parallel with the ... in parallel with the coil D. ammeter by placing a low resistance in parallel with the coil

Last Answer : Answer: D