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
Last Answer : Answer: A
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
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
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 : Which of the following statements represents the action of a megohmmeter when testing a small capacitor in good condition? A. The meter pointer should immediately swing to the maximum resistance value ... . D. The meter pointer should immediately swing to a high reading and gradually decrease.
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
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
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
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
Description : The ground indicating light on the main electrical switchboard is indicating a ground. The best procedure for locating the grounded circuit is to _____________. A. trace the circuit paths while looking for ... a time, until the lights no longer indicate a ground D. check all circuits for continuity
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
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
Description : When testing a capacitor with an analog type ohmmeter, a good capacitor will be indicated when _____________. A. there is no meter deflection B. the meter deflects to a low resistance value and ... deflects to a low resistance value and increases rapidly to a higher value, but stays fairly low
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
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
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
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
Description : If all three ground-detection lamps continue to burn at equal intensity after the test button is depressed and released, which of the listed conditions is indicated? A. No grounds exist B. All three phases are grounded C. The test switch is faulty D. The current transformers are shorted out
Description : On a switchboard, if all three ground detection lamps remain burning at half intensity when the test button is depressed, which of the listed conditions is indicated? A. No grounds exist. B. All three phases are grounded. C. The test switch is grounded. D. The current transformers are shorted.
Description : A ground on a particular phase of a three-phase low voltage distribution system would be indicated by a _____________. A. high switchboard wattmeter reading B. low switchboard wattmeter reading C. dark or dim switchboard ground detecting light D. bright switchboard ground detecting light
Description : A current-carrying conductor making electrical contact with a wiring conduit will be indicated by a _____________. A. high switchboard wattmeter reading B. totally dark switchboard ground detecting light C. low switchboard wattmeter reading D. all of the above
Description : A current-carrying conductor makes accidental contact with a wiring conduit. This will be indicated by a _____________. A. low switchboard wattmeter reading B. high switchboard wattmeter reading C. darkened switchboard ground detecting lamp D. darkened switchboard synchronizing lamps
Description : A current carrying conductor making an electrical contact with a wiring metal conduit is indicated by a _____________. A. low switchboard wattmeter reading B. reading of 1.0 on the power factor meter C. high switchboard voltmeter reading D. totally darkened switchboard ground-detecting light
Last Answer : Answer: D
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
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.
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
Description : Violent gassing from a lead-acid battery while it is being charged, indicates that the _____________. A. plate separators are grounded B. battery compartment ventilation is inadequate C. electrolyte specific gravity is too low D. charging rate is too high
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
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
Description : In which of the situations listed will a megohmmeter give the most accurate readings? A. While the machine is in operation. B. While the machine is discharging static electricity. C. Immediately prior to ... machine. D. When the machine has been shut down and grounded for a period of 15 minutes.
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
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
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
Description : In the system shown in the illustration, the station at section I is unable to signal any other station nor is any other station able to signal the station in section I. The station can, however, ring ... only a single station to respond to itself. D. The switch at component 'C' is stuck open.
Description : With both ends of a three conductor cable disconnected and arranged without the conductors touching each other, an ohmmeter reading of 'zero' ohms between the ends of one conductor would indicate _____________. A. continuity B. a partial ground C. the resistance is infinite D. a short circuit
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
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
Description : What is the resistance value indicated on the multimeter scale illustrated, if the range switch is set at R X 100, and the needle is at the position indicated by the letter 'R'? EL-0047 A. 6.0 ohms B. 162.5 ohms C. 600 ohms D. 16,250 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 100, and the needle is at the position indicated by the letter 'Y'? EL-0047 A. 220 ohms B. 240 ohms C. 2,400 ohms D. 24,000 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'A'? EL-0047 A. 10 ohms B. 100 ohms C. 200 ohms D. 1,000 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'F'? EL-0047 A. 0.6 ohms B. 6 ohms C. 9.6 ohms D. .38 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'D'? EL-0047 A. 7.8 ohms B. 8 ohms C. 3.6 ohms D. .36 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'R'? EL-0047 A. 6 ohms B. 6.8 ohms C. 1.7 ohms D. 167 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'X'? EL-0047 A. 8 ohms B. 6.2 ohms C. 1.57 ohms D. 150 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'C'? EL-0047 A. 1.3 ohms B. 4.8 ohms C. 13 ohms D. 121 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1, and the needle is at the position indicated by the letter 'B'? EL-0047 A. 1.45 ohms B. 7.2 ohms C. 37 ohms D. 70 ohms
Description : What is the resistance value indicated by the multimeter scale illustrated, if the range switch is set at R X 1 and the needle is at the position indicated by the letter 'Y'? EL-0047 A. 2.2 ohms B. 24 ohms C. 240 ohms D. 2,400 ohms
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.
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