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

1 Answer

Answer :

Answer: C  

Related questions

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 : 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 : 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 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 : If you obtain a low resistance reading with a megohmmeter connected between terminals 'A' and 'C' of the three-phase, wye-connected winding shown in the illustration, there is __________. EL-0074 A. no open circuit ... 'B' C. an open circuit between 'A' and 'C' D. an open circuit in both windings

Last Answer : Answer: A

Description : A series wound DC motor has its armature and field connected in series with a resistor. When the motor is disconnected from its power supply, this motor will exemplify __________. A. the ... the proper connections for an automatic strip heater C. a reversing controller circuit D. dynamic braking

Last Answer : Answer: D

Description : In the illustration, the component VR2 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to terminal ... 2 at 9.1 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Last Answer : Answer: C

Description : In the illustration, the component VR1 on the A1 AMPLIFIER MODULE is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply from common B. a variable resistor diode to control the output to ... terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

Last Answer : Answer: A

Description : In the illustration, the component VR1 on the A1A1 PCB is _________. EL-0060 A. a zener diode to regulate the +9 volt power supply B. a variable resistor diode to control the output to terminal 9 that controls ... terminal 9 at 6.6 volts DC D. a tunnel diode with a breakdown voltage of 6.6 Volts DC

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 : 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 : 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 : Which one of the following statements for a dc machine which is provided with inter pole winding (IW) as well as compensating winding (CW) is correct a) Both IW and CW are connected in ... parallel with Armature winding d) CW connected in series but IW is connected in parallel with Armature winding

Last Answer : Ans: Both IW and CW are connected in series with Armature winding

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

Last Answer : Answer: C

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 : An open in the armature of a DC motor is suspected, but is not found by visual inspection of the commutator. The next step in troubleshooting this problem is to ________________. A. conduct a ... windings C. conduct an insulation resistance test of the armature D. test the commutator for a ground

Last Answer : Answer: A

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 : 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 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 using a megohmmeter to determine which shunt field coil is grounded in a DC machine, you must ____________. A. insulate the field frame from the ship's hull B. disconnect each shunt ... C. use a motor driven high capacity megohmmeter D. remove all main line lead connections before testing

Last Answer : Answer: B

Description : An adjustable resistor, whose resistance can be changed without opening the circuit in which it is connected, is called a _____________. A. bleeder resistor B. rheostat C. bridge D. variable shunt strip

Last Answer : Answer: B

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 : The advantage(s) of the method of D.C. motor speed control shown in the illustration is/are ______________. EL-0101 A. elimination of armature starting resistor losses B. elimination of speed instability with variable loads C. the ease of reversing motor direction D. all of the above

Last Answer : Answer: D

Description : The number of parallel paths in armature winding of four pole wave winding connected dc machine having 22 coil sides is (1) 4 (2) 22 (3) 2 (4) 11 

Last Answer : Ans- Option (3) because wave winding always have 2 parallel paths

Description :  The number of parallel paths in the armature winding of a 4 -pole, wave connected d.c. machine having 28 coilside is : -  a) 28 b) 14 c) 4 d) 2

Last Answer : 2

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 : cooling is the process of dissipating the armature and field winding losses to a cooling medium circulating within the winding insulation wall (a) Direct (b) Indirect (c) Conventional (d) Any ofthe above

Last Answer : (a) Direct

Description : Three factors responsible for the change in voltage as load is applied to an AC generator are: 1) the drop in resistance in the armature circuit, 2) the change in flux, and 3) the ____________. A. armature winding speed B. inductance load drop C. coil pitch factor D. armature reactance voltage drop

Last Answer : Answer: D

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

Description : The arrow drawn through the resistor shown in the illustration indicates that it is _____________. EL-0086 A. for use in low power applications B. a carbon composition type C. a wire-wound type D. one whose resistance is variable

Last Answer : Answer: D

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 : 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

Description : Which of the following statements is true concerning all three-phase alternators? A. Each has three separate but identical armature windings acted on by one system of rotating magnets. B. Each has one ... The three phases always provide power to the load through three sets of slip rings and brushes.

Last Answer : Answer: A

Description : A two-terminal variable resistor is known as a? A.potentiometer B.thermistor C.rheostat D.wiper

Last Answer : A two-terminal variable resistor is known as a? A.potentiometer B.thermistor C.rheostat D.wiper

Description : Which of the instruments listed should always be connected in series with a circuit? A. Ammeter B. Megohmmeter C. Wattmeter D. Voltmeter

Last Answer : Answer: A

Description : Aluminium is not used as winding wire for the armature of a dc machine because  (1) aluminium has low resistivity (2) a large winding space is taken by aluminium conductors and creates ... ) the thermal conductivity of aluminium is low (4) aluminium has low conductivity as compared to copper

Last Answer : Aluminium is not used as winding wire for the armature of a dc machine because  (2) a large winding space is taken by aluminium conductors and creates jointing problems (3) the thermal conductivity of aluminium is low (4) aluminium has low conductivity as compared to copper

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

Description : Motor controllers are seldom troubled with grounds because _____________. A. the auxiliary contacts have a high resistance connection B. the contactors and relays are mounted on a nonconducting panel ... individual series-connected units D. there are separate switches for the motor and the control

Last Answer : Answer: B

Description : Which of the following losses is/are present in every direct current generator armature? A. Winding copper loss B. Core eddy current loss C. Magnetic hysteresis loss D. All of the above.

Last Answer : Answer: D

Description : Which type of winding is preferred for armature windings of alternator? Why?

Last Answer : Double layer, short pitched and distributed type of armature winding. It eliminates high frequency harmonics hence it makes induced emf more sinusoidal.

Description : In DC generators, armature reaction is produced actually by (A) Its field current. (B) Armature conductors. (C) Field pole winding. (D) Load current in armature.

Last Answer : Ans: D Because load current in armature gives rise to armature mmf which react with main field mmf.

Description : The purpose of resistor bank 'R1-R5' in the winch circuit shown in the illustration is to ______________. EL-0102 A. limit armature current in lower and 'series field' current in hoist to ... required speeds D. regulate the strength of the brake solenoid 'B1-B2' in both directions of operation

Last Answer : Answer: C

Description : A 200 V dc shunt motor is running at 1000 rpm and drawing a current of 10 A. Its armature winding resistance is 2 Ohm. It. is braked by plugging. The resistance to be connected in series with armature to restrict armature current to 10 A, is

Last Answer : A 200 V dc shunt motor is running at 1000 rpm and drawing a current of 10 A. Its armature winding resistance is 2 Ohm. It. is braked by plugging. The resistance to be connected in series with armature to restrict armature current to 10 A, is 36 Ohm