When a megohmmeter is used to test the dielectric strength of wire insulation, the initial dip of the pointer toward 'zero' is caused by _____________. A. good insulation B. the leakage of current along the surface of dirty insulation C. the capacitance of the circuit D. the dielectric absorption effect of the insulation

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Answer: C

Related questions

Description : When a megohmmeter is used to test the insulation of a large motor, the initial dip of the pointer toward 'zero' is caused by ____________. A. good insulation B. the capacitance of the ... of the current along the surface of dirty insulation D. the dielectric-absorption effect of the insulation

Last Answer : Answer: B

Description : When using a megohmmeter to test the dielectric strength of wire insulation, a continuous series of slight downscale kicks by the pointer is result of ____________. A. good insulation B. the ... dirty insulation C. the capacitance of the windings D. the dielectric-absorption effect of the insulation

Last Answer : Answer: B

Description : When a megohmmeter is used to test insulation, the gradual rise of the pointer reading as a result of continued cranking, is caused by _____________. A. good conductor resistance B. the ... insulation C. the inductive reactance of the windings D. the dielectric-absorption effect of the insulation

Last Answer : Answer: D

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

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

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

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

Description : A megohmmeter is used to measure _____________. A. voltage B. dielectric strength C. current D. power

Last Answer : Answer: B

Description : Before testing insulation with a megohmmeter, the windings of large machines should be grounded for about 15 minutes just prior to the test as the ______________. A. insulation may be damaged ... number of leakage paths D. larger machines may acquire a charge of static electricity during operation

Last Answer : Answer: D

Description : Before testing insulation with a megohmmeter, the windings of large machines should be grounded for about 15 minutes just prior to the test, because the ___________. A. static charge of the machine ... number of leakage paths C. insulation may be damaged D. insulation may be covered with moisture

Last Answer : Answer: A

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

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

Description : On tank vessels with an electrically-driven capstan, the motor should be meggered periodically to test _____________. A. insulation resistance B. eddy currents C. capacitance D. armature reactance

Last Answer : Answer: A

Description : A switchboard ammeter indicates a reading slightly above 'zero' when the leads are disconnected, this is caused by _____________. A. mechanical misalignment of the meter pointer B. a poor ground for the meter case C. static electricity in the air D. capacitors inside the meter storing charges

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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

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Description : You are testing the insulation in an AC generator with a megohmeter. The resistance value of a dry, clean winding will ____________. A. continue to rise as the test potential is maintained, ... fairly steady after 5 to 7 minutes D. stabilize after approximately 2 to 4 minutes of fluctuation

Last Answer : Answer: A

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

Description : 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 ____________________. A. power supply B. variable resistor C. frame of the machine D. armature

Last Answer : Answer: C

Description : When using a multimeter for resistance measurements, it should be calibrated by clipping the loose ends of the leads together and _____________. A. setting the instrument pointer at 'zero' ohms B. ... the plus and minus terminals D. using a special purpose resistance measuring instrument (a bridge)

Last Answer : Answer: A

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

Description : A grounded switch or cable will be indicated by a megohmmeter reading of _____________. A. infinity B. 'zero' C. being unsteady in the high range D. being unsteady in the low range

Last Answer : Answer: B

Description : Which of the following statements about copper wire sized by the AWG rating is correct? A. Number 12 AWG wire has a higher current rating than number 10 AWG wire. B. Number 10 AWG wire has a higher ... Number 12 AWG wire at 25°C has more resistance per 1000 feet than No. 10 AWG wire at 25°C.

Last Answer : Answer: D

Description : Which of the following statements concerning copper wire sized by AWG numbers is correct? A. Number 12 AWG wire has a higher current rating than 10 AWG wire. B. Number 12 AWG wire at 25°C has more ... dielectric strength than 12 AWG wire. D. Number 12 AWG wire is larger than number 10 AWG wire.

Last Answer : Answer: B

Description : When the current flow through a copper wire increases, its _____________. A. resistance will decrease B. insulation will burn C. temperature will increase D. conductivity will increase

Last Answer : Answer: C

Description : The removal of paint from electrical equipment, such as generators, should be cautiously undertaken because ____________. A. the mechanical shock of paint removal lessens the dielectric strength ... phase windings frequently become isolated from each other due to dust interference at the terminals

Last Answer : Answer: B

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

Description : Which of the following conditions indicates a short circuited capacitor when checking its condition with an ohmmeter? A. The capacitor shows charging, but the final resistance reading is appreciably less ... moves quickly to the low resistance side of the scale, then slowly recedes toward infinity.

Last Answer : Answer: B

Description : Multiple grounds have developed and were initialy indicated by the grounddetecting system as one ground. The FIRST step in locating the grounds is to _____________. A. examine the main bus bars ... no longer indicates any grounds C. change over generators D. check each circuit with a megohmmeter

Last Answer : Answer: B

Description : A ground is indicated by the ground-detecting system on the main electrical switchboard. The FIRST step in locating the actual ground is to _____________. A. close all circuit breakers in ... ground detection system indicates normal C. change over generators D. check each circuit with a megohmmeter

Last Answer : Answer: B

Description : Which of the listed statements is correct when using an analog multimeter as an ohmmeter? A. The pointer should be adjusted to zero each time a new resistance range is selected. B. The ... C. Ohmmeters are not sufficiently sized to measure conductor insulation resistance. D. All of the above.

Last Answer : Answer: D

Description : Sparking at the brushes of a running motor could be an indication of _____________. A. normal operation B. a dirty commutator C. increased brush capacity D. water vapor absorption

Last Answer : Answer: B

Description : You are attempting to parallel two AC generators and the synchroscope pointer stops at a position other than 0°. If you close the circuit breaker at this moment _____________. A. the incoming ... hazardous condition will be created by the incoming machine being at a higher frequency than the bus

Last Answer : Answer: C

Description : Before using a volt-ohmmeter to measure resistance readings, you should _____________. A. replace all batteries B. test the insulation resistance of the leads C. make sure the test leads do not touch D. hold the leads together and 'zero' the meter

Last Answer : Answer: D

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

Description : A megohmmeter is connected to each end of an individual motor winding. A low ohm reading indicates ____________. A. an open coil B. a loose coil C. good continuity D. a dirty coil

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Description : Capacitance is the property of an electric circuit opposing a change in the _____________. A. current in the circuit B. voltage in the circuit C. inductance in the circuit D. resistance in the circuit

Last Answer : Answer: B

Description : Capacitance in an AC circuit will _____________. A. stop current flow once the capacitor is fully charged B. allow current flow in only one direction C. oppose any change in circuit voltage D. rectify the current

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Description : Basically, a magnetic amplifier is a saturable reactor with the addition of _____________. A. AC to the bias winding B. variable capacitance to all windings C. eddy current protectors D. a rectifier in the load circuit

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Description : The final step in testing a circuit for a ground involves the use of a megohmmeter. A grounded switch or cable will be indicated by a megohmmeter reading of ____________. A. 'zero' B. infinity C. steady in the high range D. unsteady in the low range

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Description : Which of the instruments listed is used to check insulation resistance? A. Magneto B. Megohmmeter C. Dynamometer D. Rheostat

Last Answer : Answer: B

Description : You are calibrating a multimeter using internal batteries to supply power for resistance measurements. However, you are unable to adjust the pointer to 'zero' using the adjustment knob. Therefore, you should ... change scales to the R X 100 scale and adjust using the 'zero ohms' adjusting knob

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Description : If the pointer on a megger fails to return to 'zero' when not being used, the _____________. A. megger is out of calibration B. megger is operating normally C. hairsprings are burned out D. pointer probably stuck in that position

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Description : If the pointer fails to return to zero when a megger is disconnected, the _____________. A. pointer is stuck B. hair springs are burned out C. megger is out of calibration D. megger is operating normally

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Description : To properly use a hook-on-type volt/ammeter to check current flow, you must FIRST _____________. A. de-energize the circuit to allow connection of the instrument in series B. hook the jaws ... test leads to the appropriate terminals D. short the test leads and calibrate the instrument to zero

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Description : State the methods used to measure insulation resistance and explain Dielectric Absorption method.

Last Answer : There are three types of tests for measuring insulation resistance:  1. Spot test reading or Short Time test  2.Time-resistance test or Dielectric absorption test or Testing methods based on the PI & DAR  3. ... and if value of PI is less than 2 and value of DAR is less than 1.25

Description : Normally, the FIRST step in troubleshooting a transistor circuit card is to _____________. A. carefully remove the transistors from the card B. give the circuit an initial test with a signal generator C. test for continuity with a low voltage DC supply D. visually inspect the card

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Description : To test fuses in an energized circuit, you should use a ____________. A. low voltage light bulb B. megohmmeter C. voltmeter D. resistance meter

Last Answer : Answer: C