Description : The circuit illustrated represents a single phase AC ground detecting system. If a ground occurs on line 'B', which of the lamps will burn the brightest? EL-0008 A. X B. Y C. Both will be equal brightness. D. both will go out.
Last Answer : Answer: A
Description : In a three-phase electrical system, three ground detecting lamps are provided. One lamp goes dark and the others increase in brightness. When the test button is pushed, all lamps have equal illumination. You ... C. there are grounds on the lines with the bright lamps D. this is a normal condition
Description : Which of the illustrated lamps would be brighter? I. X II. Y EL-0008 A. I only B. II only C. Both I and II would be equally bright D. Neither would be lit
Description : In the illustrated ground detection system with a ground on phase A, if the switch is opened __________. EL-0009 A. lamp A will dim or go out depending on the severity of the ground B. all three ... lamp A will be brighter D. lamp A will start flickering if the ground is in an AC induction motor
Last Answer : Answer: B
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 : If all of the ground detection lamps burn with equal brilliance, whether the test button is depressed or released, then ___________. A. no grounds exist B. all phases are grounded C. all lamps show a ground D. all of the above
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 : If the illustrated motor fails to start and gives a loud hum when the start button is pushed, the problem is ________. EL-0007 A. one of the phases to the motor is not energized because of ... electrical distribution system D. 'OL1' is open because of 'T1' overload causing the motor to single phase
Description : In the illustrated test, if the lamp fails to light on any of the three windings then _________. EL-0027 A. all three windings are grounded and the motor should be sent out for repair B. ... the motor controller and the controller should be checked D. the test should be redone at a higher voltage
Last Answer : Answer: C
Description : If the illustrated test is being performed to determine which winding is grounded and the light does not come on then __________. EL-0027 A. winding is grounded and you should continue on to the ... the windings but probabily in the pecker head, you should check and retape the line lead connections
Description : Which of the following statements is true regarding the illustrated circuit? El-0069 A. This full wave bridge should never be used aboard ship because the ground on lead 'A' will show on ... be direct current suitable for electronic circuits requiring voltage regulation. D. All the above are true.
Description : A three-phase electrical system is equipped with ground detecting lamps. If one of the lamp goes dark and the other two burn normally before and after the test switch is operated, this indicates _______________. ... of the three phases D. the voltage to the dark lamp is less than that of the system
Description : In a three-phase electrical system, three ground detecting lamps are provided. If all three lamps REMAIN at half-brilliance when the ground detecting test switch is operated, ______________. A. there is a ... must be replaced C. there are no grounds present D. the light bulbs are of improper voltage
Description : A ground in an electrical circuit outside the engine room _____________. A. cannot be detected under normal conditions B. is of no consequence to engineering personnel C. is indicated at the branch circuit breaker panel D. is indicated by the ground detecting lamps on the main switchboard
Last Answer : Answer: D
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 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 : If the electricity represented by the wave form in 'B' were applied to the left side of the illustrated circuit, the output on the right side would be ____________. EL-0064 A. direct current with the ... lower lead D. clipped to a value equal to the square root of 3 times the input voltage value
Description : In electronic circuits, DC voltages can be positive (+) or negative (-) when measured with respect to the _________. A. printed circuit board 'common' trace B. chassis, console frame or hull 'ground' C. analogue or digital circuitry 'common' bus D. all of the above
Description : When the motor shown in the illustration is running and the stop button is pushed, which of the following statements will hold true? EL-0010 A. Coil 'M' will now be energized. B. Coil 'CR' will now be energized. C. Contact 'M' will close as contact 'CR' opens. D. Contacts 'M' and 'CR' will open.
Description : As shown in the illustration, which of the operations listed will happen when the 'jog button' is pushed? EL-0010 A. Coil 'CR' closes the normally open 'CR' contacts. B. Coil 'M' opens contact 'M'. C. Coil 'M' closes contact 'M'. D. Contact 'M' remains open despite the jog button being pushed.
Description : The motor starts when the start button in the illustration is pushed, but stops when the button is released the trouble is _________. EL-0007 A. the incorrect thermal overload coil B. a faulty 'M' coil C. a dirty contact on the Disc.Sw. at 'L3' D. a faulty holding relay contact
Description : Which of the following statements is correct concerning the circuits in a sound powered telephone system? A. The ringing circuit is composed of only one common wire to ground. B. The common ... connected to each station. D. The talking and calling circuits are electrically dependent upon each other.
Description : The devices labeled 'L' in the illustration are _________. EL-0003 A. load lights indicating that the generator breaker is closed and the generator is supplying power to the main bus B. ... o'clock position the lights are at their dimmest or out indicating the the generators are in phase
Description : A ground detection system is shown in the illustration for a three-phase ungrounded distribution system. Which of the following statements describes the conditions indicated if a full ground occurs in line 'A'? EL-0009 A ... . D. Lamp 'A' will go out and Lamps 'B' and 'C' will burn brightly.
Description : In the schematic diagram of the DC compound generator shown in the illustration, the positive ammeter reading is 500 amps and the negative ammeter reading is 475 amps. What is the current flow through the neutral bus? EL-0037 A. 0 amp B. 12.5 amp C. 25 amp D. 975 amp
Description : While paralleling two (2) AC generators using synchronizing lamps only, both lamps will go dark when the generators are ____________. A. running at the same speed B. grounded C. of the same polarity D. in phase
Description : In the illustrated circuit, if the input to leads 'B' and 'Y' was 24 VDC the output between 'A' and 'X' will be _________. EL-0069 A. 24 VDC B. 22.8 VDC, 24 VDC minus the 1.2 VDC voltage drop across two diodes C. undeterminable without knowing the turns ratio of the transformer D. 0 VDC
Description : The illustrated test is being conducted on the motor shown in the illustration, if the lamp lights dimly then ________. EL-0027 A. the bulb needs to be changed to one with a higher wattage rating B. ... D. a ground or partial ground is indicated, a check with a megger should confirm the lamp test
Description : If fuse 'F-1' in the illustrated schematic diagram opens, ____________. EL-0017 A. the motor will run slowly B. 'A-1' and 'A-2' will open C. the motor will not start D. the start button will jam in the closed position
Description : In the illustrated schematic diagram, which of the listed devices prevents the forward and reversing coils from being energized simultaneously? EL-0011 A. An 'either-or' interlock B. A mechanical interlock C. Blowout coils D. A stop button
Description : Refering to the illustrated schematic diagram, which of the following statements is true when the motor is running in the forward direction? EL-0011 A. Normally-open contacts '4-5' are closed. B. Current ... switch. C. Normally-closed contacts 'R' are open. D. The blowout coils must be closed.
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
Description : The potentiometers shown in the illustration are supplied with both (+) and (-) voltages as well as a reference to ground ________________. EL-0095 A. so there is always a spare power ... , the other for relay operation and the potentiometers are in positions where they can be accidentally touched
Description : The ground detection system, shown in the illustration for a low-voltage, threephase system has a ground in line 'A'. Therefore, lamp 'A' will burn ____________. EL-0009 A. dimly or be out, and lamps 'B' and ... and 'C' will burn dimly or be out D. brightly, and lamps 'B' and 'C' will burn normally
Description : In the illustrated 450 VAC system, what should be provided between the bus and the device labeled 'F'? EL-0003 A. a potential transformer B. a current transformer C. an emergency disconnect device D. an audible alarm and indicating light
Description : Which of the following statements is correct for the illustrated circuit? EL-0020 A. 'R1', 'R2', and 'R3' are connected in series. B. 'R1', 'R2', and 'R3' are connected in parallel. C. The voltages measured across 'R1', 'R2', and 'R3' are equal. D. The total resistance equals 1/R1 + 1/R2 + 1/R
Description : The illustrated circuit is a wheatstone bridge. If the meter 'G' reads 0 with the switch closed then ________. EL-0024 A. the current through R1 - R2 is equal to the current through R3 - Rx B. the voltage ... of E C. the resistance of Rx is equal to the resistance of R2 D. all the above are true
Description : In the illustrated motor controller circuit, which statment is true? EL-0023 A. The high and low speed lights operate at less than line voltage with a resistor in series. B. This controller can be ... . The wattage of the high speed light must be greater than the wattage of the low speed light.
Description : In the illustrated one line diagram, if the turbo generator fails, the diesel generator_________. EL-0014 A. will automaticly start and supply power to the emergency power switchboard, the power ... be manually started but once running will supply power to the lighting main through the ABT.
Description : A motor controller contains three selector push buttons labeled 'start', 'jog', and 'stop'. When the 'jog' button is pushed, the motor _____________. A. will run continuously after the 'jog' button is ... 'jog' and 'start' buttons are pushed D. will not stop unless the 'stop' button is pushed
Description : If the supply voltage is 220 volts 60 Hz, what is the operating voltage of the motor controller circuitry illustrated? EL-0011 A. 110 volts DC B. 110 volts AC C. 220 volts DC D. 220 volts AC
Description : If the illustrated device has a step-up ratio of 10 to 1 what voltage be measured at the secondary shortly after the primary of the device is connected to 110 volts DC with a current of 12 amps? EL-0055 A. 0 volts B. 110 volts C. 1000 volts D. 1100 volts
Description : The illustrated device is a _______. EL-0064 A. full wave bridge rectifier B. half wave bridge rectifier C. solid state voltage regulator D. direct current (DC) filter
Description : As shown in the illustration, the circuit has been on the line for several days when component 'E1' burns out. The operator receives an alarm, switches over 'B' to energize the standby ... than required for the circuit therefore limiting the current through the alarm relay which will not pick up
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 : Component 'C' in section 'I' shown in the illustration represent ____________. EL-0093 A. a selectable holding coil arrangement B. a 'fuse blown' indicator circuit C. 'reset' and 'trouble' lamps D. a handset with switch and voice elements
Description : A voltmeter located on a control panel has been operating correctly for six months, suddenly burns out. After removing it, it is found that neither side of the meter has been grounded. When ... side and the ground C. installed exactly as the old installation D. grounded to the positive side
Description : What is the direction of current through the load resistor in the circuit shown in the illustration? EL-0085 A. Always from point 'Z' to the grounded end. B. Always from the grounded end to ... on the instantaneous polarity at point 'W'. D. It cannot be determined without a directional ammeter.
Description : Which of the listed conditions might contribute to very rapid wearing of a DC machine's commutator bars? A. A grounded commutator bar B. Using improper carbon brushes C. Aligning the front and rear mica V-rings improperly D. An open circuit in the armature
Description : The illustrated lead acid battery is about to be placed in service. The positive plate labeled 'D' is made of_______. EL-0031 A. sponge lead (Pb) B. lead peroxide (PbO2) C. lead sulfate (PbSO4) D. a depolarizing mix