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As shown in the illustrated electric propulsion control scheme for a twin screw vessel, when the two shaft speeds are wi...
Referring to the illustration of a twin-screw diesel-electric AC propulsion drive system, concerning the various control...
In the twin screw diesel-electric AC propulsion system shown in the illustration, what type of propulsion motors is used...
Referring to the illustration of a twin-screw diesel-electric AC propulsion drive system, if either the port propulsion ...
What statement is true concerning temporary protective grounds used to establish an equipotential zone for the purposes ...
Before any work on electrical or electronic equipment is performed, which of the following precautions should be carried...
For the purposes of safety and determining the shock hazard, nominal voltage is defined as the normal electrical system ...
When performing an absence-of-voltage test, a live-dead-live test may be required in conjunction with the absence-of-vol...
When performing an absence-of-voltage test before commencing repair work, at the minimum where must the absence-of-volta...
When taking voltage measurements, for reasons of electrical safety, what should be the proper sequence of actions?
Why should an electrical worker determine the nominal voltage of a circuit first before making contact with the circuit?...
In figure "A" of the illustration, the battery Vbb and resistor Rb are in the circuit for what purpose? Illustration EL-...
Which of the following expresses the relationship of the AC input frequency and DC ripple output frequency in a full wa...
As shown in figure "C" of the illustration, what are the purposes of the coupling capacitor Cc and the bypass capacitor ...
What does the symbol labeled "OL" represent as shown in the power circuit on lines T1 and T3 to the motor as shown in fi...
Which of the following statements concerning figure "6" of the illustration is true? Illustration EL-0026
In figure "1" of the illustration, what type of circuit breaker trip element is featured? Illustration EL-0033
Which of the electrical schematic symbols represents a normally closed limit switch? Illustration EL-0059
Which of the illustrated resistors represents the schematic symbol shown in figure "B"? Illustration EL-0021
As shown in figure "6" of the illustration, what does the symbol represent as used in electrical drawings? Illustrations...
As shown in the illustrated devices and symbols, which of the symbols represents a standard normally closed relay contac...
Which figure represents the schematic symbol shown in figure "2"? Illustration EL-0034
Which of the following electrical schematic symbols represents a normally closed flow switch? Illustration EL-0059 ...
Which of the electronic schematic symbols represents the capacitor illustrated in figure 1 of the illustration? Illustra...
As shown in figure "B" of the illustration, when the DC motor in figure "A" is operating at base speed what are the arma...
In figure "B" of the illustrated circuit, if the resistance of R1 is 10 ohms, R2 is 10 ohms, and R3 is 10 ohms, what is ...
What would be the total current in figure "A" of the circuit illustrated if the value of capacitor C1 was 100 microfarad...
What would be the terminal voltage and ampere-hour capacity of the battery bank illustrated if each battery was rated at...
How is reversal of a DC propulsion motor achieved?
As shown in the illustration, which of the following pieces of equipment is supplied with a circuit breaker providing bo...
What is a bus disconnect link used to isolate?
As shown in figures "E" and "F" of the pictured high voltage rack mounted circuit breaker, which figure represents the c...
By what means does a molded-case breaker provide protection against short circuits?
In addition to insulating the outboard bearing pedestal to prevent shaft currents in an alternator, what else must be in...
To prevent shaft currents in an alternator, the outboard bearing shell or outboard bearing pedestal is insulated. If the...
Which of the listed classes of electrical insulation is suited for the highest operating temperature?
Which of the following procedures should be used to maintain a large electric motor during periods of inactivity?
When troubleshooting a printed circuit board, one technique that can be used is swapping the suspected damaged board wit...
What problem with a printed circuit board may resolve itself once a board is removed from its edge card connector and th...
As shown in the illustrated adaptive digital steering control system functional block diagram and listed system interfac...
As shown in the illustrated echo sounding display unit and control panel and pertinent operating characteristic tables, ...
Using the trouble analysis chart and faults table provided in the illustrations, if the adaptive digital steering system...
Using the trouble analysis chart and faults table provided in the illustration, if the gyrocompass was malfunctioning, b...
What equipment for modern SCR rectified DC propulsion drive systems is usually included in the package?
What is the name of a TCP/IP application run from the command prompt that sends datagrams once every second in the hope ...
A very useful Windows utility for discovering or verifying IP addressing information of a network is "ipconfig". How is ...
After a black out onboard and once ships power has been restored, the engine room supply fans must be started manually. ...
What computer network device maintenance procedure is recommended to be increased in frequency when the equipment is loc...
What is the reason that some electric cables are formed of stranded wire?
How are the line losses in a distribution circuit kept to a minimum?
Why are large cable sizes often formed as individual conductors comprised of several smaller strands?
As shown in the illustration, which of the following pieces of equipment is fed with the three conductor cable with the ...
When electrical cables penetrate watertight bulkheads, what must be provided for?
As shown in figure "A" of the illustration, with respect to the common equipment grounding conductor, what statement is ...
What type of electric propulsion system converter is shown in the illustration? Illustration EL-0155
The conversion of constant frequency power into adjustable frequency power in a modern AC propulsion drive system is com...
As shown in the illustration of a DC diesel-electric propulsion drive system, what would be the set up contactor configu...
Refer to the two-generator, two-motor, DC diesel-electric drive propulsion system simplified schematic shown in the illu...
While standing an "at sea watch" onboard a modern rectified DC diesel-electric drive ship you notice the transformer cor...
If the values of ‘C1’ and ‘R1’ shown in the illustration were 1 microfarad and 3 megohms respectively, which of the list...
Using the portable harmonic analyzer shown in figure "A", if the clamp-on test lead is connected as shown in figure "C" ...
A fuse is the most common type of protection against a short-circuit fault in LV distribution circuits, motor circuits a...
Fuses are sometimes placed in series with a thermal trip-type circuit breaker. What is the purpose of a fuse used in thi...
Due to the operating characteristics of the system, time lag fuses (or dual-element fuses) are necessary for use in what...
Why is it necessary to perform periodic testing of correctly rated and properly installed circuit breakers?
If a digital multimeter is set up as shown in figure "B" of the illustration to test a capacitor, what would the display...
What is the name of the device shown in figure "1" of the illustration? Illustration EL-0068
If a digital multimeter is set up as shown in figure "A" of the illustration to test a capacitor, what would the display...
In order to check the performance of a transistor removed from its circuit, what meter or tester should be used?
What would be the indication of a burned-out LED?
Which of the procedures or conditions listed could result in damaging a transistor beyond repair?
Which of the following conditions would most likely lead to the failure of a resistor due to overheating?
To conduct an in-circuit test of a transistor, what meter or tester should be used?
When using an ohmmeter to test a semiconductor diode, you find a low resistance in both the forward and reverse bias dir...
If a digital multimeter is setup as shown in figures "A" and "B" to test a silicon diode, what is the status of the diod...
Which of the following actions can be carried out in order to prevent thermal runaway in a transistor?
You have installed a Zener diode in parallel with a load. While measuring the voltage across the Zener diode it is found...
To avoid misleading readings when testing the discrete semiconductor components of a printed circuit board when testing ...
How should the shunt used in an ammeter be connected?
To properly use a clamp-on type ammeter to check current flow, what must be done FIRST?
Why are external shunts sometimes used with ammeters?
Which of the listed temperature measuring devices installed on a large turbo-electric alternating current propulsion gen...
An electric propulsion drive system in which the propulsion generator supplies power to both the propulsion motor and sh...
Propulsion AC generators creating 4160 VAC use transformers to provide nominally 120 VAC to the automatic voltage regul...
Which of the listed devices is most likely to be installed on a large modern diesel- electric alternating current propul...
What statement is true concerning random access memory (RAM)?
What statement is true concerning read only memory (ROM)?
Which of the following devices represents primary storage, where the processor is able to directly read instructions and...
Modern ships use multiple computers arranged in a client/server network to perform various shipboard functions. What typ...
Which of the following data communication cable types offers the greatest immunity to electromagnetic "noise"?
What condition associated with a lead-acid battery cell can cause the plates to partially short-out and cause the cell t...
Which of the problems listed will occur if a lead-acid battery is allowed to remain in a discharged condition for a long...
In a 60 Hz AC system, what is the duration in seconds for one complete cycle?
A three-phase alternator is operating at 450 volts with the switchboard ammeter indicating 300 amps. The kW meter curren...
An electrical component is connected across a 120 volt 60 hertz AC supply. What is the current drawn by the component if...
A turbo generator has a rated output of 1200 kW at 60 Hertz, with a no load frequency of 61.5 Hertz. What is its speed ...
An AC generator produces 60 Hz at 1800 RPM. If the generator speed is increased to 1830 RPM, what will happen to the fr...
The apparent power supplied to a motor is six kilovolt amps at 120 volts. What is the impedance of the motor?
In mounting a transducer for a depth sounding system, what would represent an ideal location?
According to the liquid crystal data display for the depth sounder shown in the illustration, what is the instantaneous ...
In viewing the liquid crystal display for the illustrated depth sounder data display unit, what should be done if the gr...
Upon failure of the normal power supply, how is the emergency generator placed on the line to feed power to the emergenc...
In preparation for paralleling generators, if the electric plant condition is as shown by graph "A", what would be the r...
As shown in figure "B" of the illustration, what is the purpose of the synchronous compensator? Illustration EL-0133 ...
Two AC generators of the same capacity are operating in parallel. One with a zero speed droop setting and the other with...
When a self-excited alternator's field has lost its residual magnetism due to a prolonged idle period, it will fail to p...
If it becomes absolutely necessary to run an alternator at lower than 5% below its rated frequency, in terms of output v...
Upon loss of field excitation of a generator operating in parallel with others, what must be done?
When a self-excited DC generator's field has lost its residual magnetism due to a prolonged idle period, it will fail to...
On a modern silicon controlled rectified diesel-electric drive system, what are the characteristics of the main propulsi...
On an older two-generator, two-motor DC diesel-electric drive system as shown in the illustration, what are the characte...
How is speed control of a DC propulsion motor accomplished?
On DC diesel-electric drives, how is the speed of the DC propulsion motor primarily controlled?
In a diesel-electric plant, raising the generator's field excitation current will have what effect on the DC propulsion ...
What would be the most likely fault if a single-phase permanent split capacitor induction motor fails to start?
As shown in the illustrated diagnostic setup checking for a reversed field pole on a ten-pole synchronous motor, if a ro...
Which of the following statements represents the reading display of a hand-cranked megohmmeter when testing a capacitor ...
As shown in figure "A" of the illustration, with a digital multimeter set up as an ohmmeter, what set of readings would ...
A digital multimeter is set up as shown in the illustration to evaluate the single-circuit stator windings of a squirrel...
What would happen if the centrifugal switch or relay, for cutting out the starting winding of a split-phase induction mo...
Which of the following problems will most likely occur if the starting winding of a split- phase induction motor failed ...
When testing the rotor of a synchronous motor for short circuits, a low voltage source is applied across the rotor coils...
As shown in the illustrated diagnostic setup for locating an open field coil of a ten- pole synchronous motor, if 240 VD...
In the illustration what is the component labeled "C"? Illustration EL-0033
Without the benefit of a specially designed enclosure window for thermo graphic analysis, what must be done to obtain ac...
Which of the listed types of lighting fixtures does the diagram shown in figure "A" of the illustration represent? Illus...
What type of circuit is represented by the diagram shown in the illustration? Illustration EL-0058
As shown in the illustration, what event would give the same indication that would occur when a stern light circuit fuse...
What is the purpose of the capacitor within component "5" of the circuit shown in figure "B" of the illustration? Illust...
As shown in the illustration, the change-over switch is what type of device? Illustration EL-0058
Refer to the simplified schematic of the Ward-Leonard drive system shown in the illustration. What statement is true con...
Refer to the simplified schematic of the various types of self-excited DC generators shown in the illustration. What is ...
The conversion of the throttle command voltage to the signal necessary to achieve the desired shaft RPM is accomplished ...
As shown in the illustrated block diagram for a distributed automation system, what statement is true concerning the uni...
As shown in figure "B" of the illustrated block diagram of the signal processing flow path, the block "TRANSDUCER" repre...
As shown in the illustrated block diagram for a digitized echo sounding system, what statement is true concerning the fu...
In the illustrated throttle control system, the amplifier 'M" functions to invert the signal received from the engine ro...
As shown in figures "A", "B", and "C" of the illustration, what is the purpose of the differential amplifier segment of ...
As shown in the illustrated block diagram for a distributed automation system, what statement is true concerning the are...
In process control terminology, continuously variable values which change without distinct increments, such as temperatu...
What are some common basic applications for the operational amplifier?
What does the circuit shown in the illustration represent? Illustration EL-0091
What would be the resistance tolerance of a carbon resistor which is color coded as red, violet, brown, and silver in ba...
What is the functional purpose of a heat sink, as frequently used with transistors?
What is the basic "control action" of a magnetic amplifier dependent upon?
What will happen to a carbon resistor operating in electrical equipment that is NOT properly cooled?
A carbon resistor has the following color bands; band 1 is yellow, band 2 is violet, band 3 is yellow, and band 4 is sil...
Although saturable reactors are extremely useful in some applications, why is their gain low?
A saturable-core reactor operates on the principle of controlling a load winding's inductance by changing the permeabili...
A carbon resistor has a resistance of 50 ohms, and a tolerance of 5 percent. What would be the respective colors indicat...
A 440/110 V single phase transformer supplies a load of 5 kW at 0.8 power factor load. What will be its primary current?...
The turn’s ratio of the step-down transformer with dual voltage secondary shown in figure "B" of the illustration is two...
What is the maximum current allowed to be drawn from the secondary of a 2 kVA step-down transformer with a turn’s ratio...
A 440/110 V single phase transformer supplies a load of 5 kW at 0.8 power factor load. What will be its secondary curren...
Refer to the simplified schematic of the Ward-Leonard drive system shown in the illustration. The DC winch exhibits norm...
Under what circumstance would a hand-held portable phase sequence indicator be used should the main switchboard mounted ...
Which of the listed statements is correct when using a digital multimeter set up as an ohmmeter?
As shown in figure "A" of the illustrated digital multimeter screen, what would be the significance of the symbol indica...
If you disconnect and arrange both ends of a conductor of a multi-conductor cable without any contact between the indivi...
Prior to using an analog multimeter set up as an ohmmeter, the leads are purposely shorted together. Which of the follow...
A resistance in a circuit of unknown value is to be tested using the voltmeter/ammeter method. How should the two meters...
As shown in figure "D" of the illustrated digital power meter, what type of single- phase load is under test for power m...
A digital multimeter, set up as a milliammeter on the 100 milliamp scale, is known to have an accuracy of plus or minus ...
What can a typical common analog or digital multimeter be used to measure?
While troubleshooting a circuit in an engine room central control console, a resistor is suspected of being faulty. Whic...
What is the most convenient instrument for measuring current, voltage and resistance?
When troubleshooting motor controllers, what is a shorted relay or contactor coil often indicated by?
If you hear a loud buzzing noise coming from a magnetic motor controller, what should you do?
Why are motor controllers seldom troubled by grounds?
As shown in the illustration, what is the purpose of the Time Delay (TR) coil in the circuit? Illustration EL-0104
In the illustrated motor controller, the motor fails to start. A voltmeter reading between 1 and 5 reads line voltage, ...
During its operation, loud buzzing and resultant welding of contacts of a magnetic relay may occur. Which of the followi...
If the contacts of a motor starter or controller fail to drop out when the 'stop' button is depressed, what could be the...
If the motor of the illustrated circuit fails to start and gives a loud hum when the start button is pushed, what is mos...
The motor starts when the start button in the illustration is pushed, but stops when the button is released. What is mos...
As shown in figure "A" and "B" of the illustration, the potable water pump is short cycling by the action of the pressur...
As shown in the illustration, what mechanism will disconnect the motor from the line in case of a sustained motor overlo...
As shown in figure "A" of the illustration, if in troubleshooting the control circuit using on-line techniques with a vo...
When completing repairs on a high voltage circuit where portable grounding straps were used for increased operator safet...
What is the most common and reliable type of circuit breaker used for high voltage practice aboard ship?
For the purposes of shipboard practice, voltages above what threshold would be considered high voltage?
By what means should motor controller contacts be routinely cleaned?
What damage may occur to the components of a winch master control switch, if the cover gasket becomes deteriorated? ...
Which of the following statements is true concerning the cleaning of electrical contacts?
Before working on an electric cargo winch master switch or controller, what should be done?
What is the greatest single cause of electrical failures?
What is meant by the term 'dielectric'?
The ground indicating light on the main electrical switchboard is indicating a ground. What is the best procedure for lo...
If a digital multimeter is set up as shown in figure "A" of the illustration, what would be displayed on the screen if t...
If a circuit breaker that utilizes built-in, current limiting fuses (CLF's), cannot be closed or reset, what may be the ...
To test fuses in an energized circuit, what testing apparatus or meter should be used?
In order to definitively determine whether or not fuse "1", shown in the illustration is blown using an on-line testing ...
In addition to short circuits and sustained overloads, in what other situation are fuses likely to blow?
When replacing a fuse with one of a ampere higher rating than the original, which of the following is true?
As shown in the illustration, which electrical symbol represents a PNP type bipolar junction transistor? Illustration EL...
Which of the listed conditions describes the effect on intrinsic semiconductor operation as a result of a temperature in...
As shown in figure "A" of the illustration, what is true concerning the illustrated frequency response curve? Illustrati...
As shown in figure "A" of the illustration, under what conditions will the thyristor conduct? Illustration EL-0154
What does the electronic symbol of figure "9" represent? Illustration EL-0065
What type of motor is generally used in DC propulsion drive systems?
Which of the following statements is true concerning the operation of modern marine electric drive DC propulsion motors?...
Referring to the illustration of a DC diesel-electric drive system, what type of DC propulsion motors are used? Illustr...
As shown in the illustrated alternator protection scheme diagram, what device provides the input to the over current inv...
Which of the following statements is TRUE concerning Azipod propulsion systems?
Which of the following statements is true concerning a large polyphase synchronous main propulsion motor as used in an e...
Assuming that the motor is capable of running with no rotor slip, what type of motor would be used in an AC propulsion d...
What statement is TRUE concerning the Azipod propulsion system?
Which of the following describes the action when the handle is moved to the "start" position of a drum-type motor contro...
As shown in figure "B" of the illustration, what statement is true concerning "regenerating" operation? Illustration EL...
With an AC synchronous electric propulsion motor driving a fixed-pitch propeller, whenever there is a direction reversal...
What is the instrument called a galvanometer used to measure?
To limit the current flow through a DC voltmeter to as low a value as possible, what is the moving coil circuit provided...
If the clock frequency input to the circuit shown in the illustration were 2 kHz, what would be indicated at the output ...
In a logic circuit, how does a NOT gate function?
Which of the listed devices may be used as a digital device?
How is a short in the shunt field of a DC motor best located?
Which of the listed conditions might contribute to very rapid wearing of a DC machine's commutator bars?
How may temporary repairs to an open DC propulsion armature coil be made, allowing continued operation until permanent r...
Besides a condition of overload, what could be a cause of an open armature connection in a DC propulsion motor?
What can insufficient brush pressure on a DC motor cause?
An open in the armature of a DC motor is suspected, but is not found by visual inspection of the commutator. What would ...
As shown in the illustration, what type of motor and motor starter are featured? Illustration EL-0137
Referring to figure "B" of the illustrated control circuit schematic diagram, which of the following statements is true ...
As shown in the illustrated steering hydraulic pump motor controller, what statement is true? Illustration EL-0119
What is the function of a shading coil as used in an AC magnetic controller?
By what means is the rotation of a three-phase induction motor reversed?
Which of the following statements is true concerning the manual motor starter diagram shown in figure "A" of the illustr...
What is the proper name for the entire device, including all subassemblies, shown in the illustration? Illustration EL-0...
As shown in figure "A" of the illustration, what is the purpose of the "test button"? EL-0178
As shown in the illustrated three-phase squirrel cage induction motor controller, what type of reduced voltage starter i...
As shown in figure "B" of the illustration, what type of overload relay for motor protection is illustrated? EL-0172 ...
What type of control circuit logic is featured in the electrical schematic diagram for the motor starting circuit shown ...
Which of the following illustrated circuit schematics provides phase failure protection for a three phase motor using lo...
With what kind of starting equipment are most three-phase induction motors of five horsepower or less started?
The design Power Factor (PF) of a vessel's electrical system is generally 0.8 - 0.9. The system's greatest load is indu...
You direct the electrician to take quarterly insulation resistance reading of the ship's critical motors. What additiona...
How is the main propeller shaft rotation of a conventional AC turbo-electric drive normally reversed? (Assume that no co...
How is the main shaft rotation on an AC diesel-electric propulsion vessel normally reversed?
Which of the listed ranges represents the specific gravity for the electrolyte of a fully charged lead-acid battery at r...
What should be performed as routine maintenance of lead acid batteries?
What should you be aware of when checking the specific gravity of the battery electrolyte with a hydrometer?
How can the charge of a lead-acid battery be restored?
What will be the freezing point of the electrolyte in a fully charged lead-acid battery as compared to a discharged batt...
For accuracy purposes, which of the following devices should be used to measure the temperature of a battery electrolyte...
In addition to high voltage circuit grounding with ground-connecting switching devices, for additional operator safety ...
For a motor rated at 3.3 kV, what would be a minimum accepted insulation resistance to hull ground as tested by an appro...
Before work may safely commence on a high voltage system, what must first be done after disconnection and isolation? ...
In order for a live-line tester to be used to test and prove dead a high voltage circuit, what must be done to verify th...
By what common means is the speed of the AC propulsion motor on a diesel- electric propulsion ship controlled?
A common method used to control the speed of a synchronous AC propulsion motor on a diesel-electric propulsion drive is ...
While standing an "at sea watch" onboard an AC diesel-electric drive ship with a synchronous propulsion motor, you notic...
An AC diesel-electric drive ship with synchronous propulsion motors has the capability for power factor correction. If t...
While underway onboard a DC diesel-electric drive ship, you notice excessive sparking of the brushes on the main propuls...
While standing "at sea watch" onboard a modern rectified DC diesel-electric drive ship you notice the transformer core t...
When a transformer is used to step down voltage, what statement is true?
What is the basic principle of operation by which a transformer works?
How are power transformers rated?
Which of the listed transformers uses a single winding to produce voltage transformation?
In a three-phase, wye-wye connected transformer, what is the relationship between line current and phase current? ...
What is the function of the autotransformers used with autotransformer starters used on some large AC motors?
Why are transformer cores laminated?
What are the operating characteristics of a step-down potential transformer in terms of the secondary load?
What is the device shown in figure "B" of the illustration between the source circuit breaker and the load? Illustration...
In the illustrated switchboard, what is the purpose of the device labeled "AM Sel. Sw."? Illustration EL-0003
What do the devices labeled "L" in Panel 2 of the illustrated switchboard represent? Illustration EL-0003
As shown in the illustrated switchboard, what is the function of the switch labeled 'PFM Sel. Sw.'? Illustration EL-000...
Which of the illustrated safety disconnect switches represents a double throw switch? Illustration EL-0176
Which of the listed sections of an emergency switchboard is used to supply power for alarm signals under emergency condi...