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

1 Answer

Answer :

Answer: B

Related questions

Description : 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 ... of dirty insulation C. the capacitance of the circuit D. the dielectric absorption effect of the insulation

Last Answer : Answer: C

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 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 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 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 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 : 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

Description : In testing a three-phase delta winding for an open circuit using a megohmmeter, you must ______________. A. test each phase with all connections intact B. measure the voltage across the open ... groups to avoid short circuiting D. open the delta-connections to avoid shunting the phase being tested

Last Answer : Answer: D

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 : A device which can be used to check the calibration of a circuit breaker is a _________________. A. 500 volt megohmmeter B. portable low voltage high current testing unit C. standard digital multimeter D. clamp-on voltmeter

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 : 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 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 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 : 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 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 : The force that causes free electrons to move in a conductor as electric current flow is called a/an _____________. A. resistant force B. electromotive force C. inductive force D. dielectric force

Last Answer : Answer: B

Description : A multimeter can be used to measure _____________. A. resistance B. voltage C. current D. all of the above

Last Answer : Answer: D

Description : The most practical way to control the voltage output of an AC generator is to vary the _____________. A. number of windings B. speed of the rotating field C. strength of the rotating magnetic field D. power factor of the load

Last Answer : Answer: C

Description : Dielectric strength of a material is (A) Its energy storage capacity (B) A magnetic property (C) Its capacity to resist the flow of current (D) Its capacity to withstand high voltage

Last Answer : (D) Its capacity to withstand high voltage

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 : 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

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

Description : The frequency of an alternator at a given RPM is determined by the _____________. A. number of turns of wire in the armature coil B. number of magnetic poles C. strength of the magnets used D. output voltage

Last Answer : Answer: B

Description : The frequency output of an operating alternator is controlled by the _____________. A. relative speed of the rotor poles B. number of turns of wire in the armature coil C. strength of the magnets used D. output voltage

Last Answer : Answer: A

Description : A saturable-core reactor operates on the principle of controlling a load winding's inductance by varying the core's _____________. A. dielectric B. permeability C. reactance D. inductance

Last Answer : Answer: B

Description : As a general rule, the first troubleshooting action to be taken in checking faulty electric control devices is to _____________. A. draw a one line diagram of the circuitry B. test all fuses and measure the line voltage C. take megger readings D. insulate the apparatus from ground

Last Answer : Answer: B

Description : An open shunt field in a direct current machine may be located by connecting the field circuit to an external power source, equal to the rated field voltage or less, and tested with a voltmeter from ... C. any suitable ground to any available line lead D. any field pole to each field coil lead

Last Answer : Answer: A

Description : Equalization of the power factors of two alternators operating in parallel is accomplished _____________. A. manually, by adjusting the governor controls B. automatically, by automatic voltage regulators ... the output of current transformers D. automatically, by the designed action of the governors

Last Answer : Answer: B

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

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

Description : Equal power factors on paralleled AC generators are maintained by an automatic _____________. A. voltage regulator B. reverse power relay C. reverse current relay D. governor control switch

Last Answer : Answer: A

Description : Decreasing the frequency in a capacitive circuit while maintaining a constant circuit voltage, will result in a/an _____________. A. increase in apparent power B. decrease in circuit current C. decrease in capacitive reactance D. decrease in total impedance

Last Answer : Answer: B

Description : The function of a stepdown potential transformer is to reduce the load _____________. A. voltage and current B. voltage and increase line current C. current and increase line voltage D. power

Last Answer : Answer: B

Description : The purpose of a motor undervoltage protection device is to _____________. A. prevent high armature current when power is restored B. start the motor at a very low voltage C. trip the load off the motor in case of fire D. protect personnel from low voltage shocks

Last Answer : Answer: A

Description : Define breakdown voltage and dielectric strength of a capacitor.

Last Answer : Breakdown Voltage: The voltage at which the dielectric material breaks down (Starts conducting or is no longer remains as an insulator) for a specified thickness, is called its breakdown ... without breaking down (without losing its dielectric property) is called its dielectric strength. 

Description : Define : (i) Dielectric strength (ii) Breakdown voltage

Last Answer : (i) Dielectric strength: The voltage which a dielectric material can withstand without breaking down (without losing its dielectric property) is called its dielectric strength. It is represented by kV/mm ... or is no longer an insulator) for a specified thickness, is its breakdown voltage. 

Description : Emulsifier protection is associated with: a) Grounding protection b) Dielectric strength protection of cables and conductors c) Lightning protection d) Fire protection

Last Answer : Ans: D

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 : The dielectric strength of a vacuum or dry air is approximately ________________. A. 450 volts/inch B. 1000 volts/inch C. 20-kv/inch D. 50-kv/inch

Last Answer : Answer: C

Description : What is meant by Dielectric strength? 

Last Answer : The maximum electrical potential gradient that a material can withstand without rupture usually specified in volts/millimeter of thickness. This also has known as electric strength. 

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 : A synchronous motor maintains synchronism with the rotating field because _____________. A. field strength varies directly with rotor slip B. DC current applied to the rotor coils causes the rotor ... the flux created by the excitation current D. the stator flux rotates in the opposite direction

Last Answer : Answer: B

Description : A multimeter can be used to directly measure _____________. A. watts B. field flux C. current D. all of the above

Last Answer : Answer: C