Description : When paralleling two AC generators, the frequency of the machine coming online, immediately prior to closing its breaker, should be ____________. A. slightly less than the oncoming generator frequency B. the ... bus frequency C. slightly greater than the bus frequency D. the same as the bus voltage
Last Answer : Answer: C
Description : You are attempting to parallel two AC generators and the synchroscope pointer is revolving slowly in the fast direction. You should _____________. A. use the governor control switch to adjust the incoming ... the 0° position D. use the field rheostat to adjust the speed of the incoming machine
Description : When paralleling two AC generators, the frequency (cycles) of the incoming generator, just prior to closing the circuit breaker, should be _____________. A. slightly less than the frequency of the generator on ... C. slightly more than the frequency of the generator on the line D. all of the above
Description : When paralleling two AC generators, the frequency of the incoming machine immediately prior to closing its breaker should be ____________. A. controlled by placing the governor switch in the automatic ... regulator C. slightly greater than the bus frequency D. slightly less than the bus frequency
Description : You are attempting to parallel two AC generators, and the synchroscope pointer is revolving fast in the clockwise direction. This indicates that the frequency of the incoming machine is _____________. A. higher ... at any pointer position D. the same as the bus frequency but out of phase with it
Last Answer : Answer: A
Description : You are attempting to parallel two AC generators and the synchroscope pointer stops at a position other than 0°. If you close the circuit breaker at this moment _____________. A. the incoming ... hazardous condition will be created by the incoming machine being at a higher frequency than the bus
Description : You are attempting to parallel two AC generators, and the synchroscope pointer is revolving in the fast direction. This indicates that the frequency of the incoming machine is _____________. A. higher ... the same as the bus frequency and the circuit breaker may be closed at any pointer position
Description : You are attempting to parallel two AC generators and the synchroscope pointer is revolving in the slow direction. This indicates that the frequency of the incoming machine is _____________. A. higher than ... same as the bus frequency, and the circuit breaker may be closed at any pointer position
Last Answer : Answer: B
Description : A diesel driven emergency generator is prevented from being paralleled with the ship's service generators by __________. A. an electrical interlock system B. an automatic paralleling trip switch C. the synchronizing oscilloscope D. the reverse current relay
Description : Why is it a good practice to have the frequency of the incoming alternator adjusted slightly higher than that of the loaded alternator when paralleling two alternators? A. This allows the oncoming machine to ... line. C. The reverse power relay is prevented from activating. D. All of the above.
Last Answer : Answer: D
Description : Which of the synchroscope illustrations depicts the appropriate direction of rotation and position for closing the circuit breaker when paralleling AC generators? EL-0053 A. A B. B C. C D. D
Description : Prior to closing the breaker when paralleling two AC generators, the recommended practice is to have the frequency of the incoming machine _____________. A. slightly less than the line frequency B. the same as the line frequency C. slightly greater than the line frequency D. all of the above
Description : You are attempting to parallel two AC generators and the synchroscope pointer stops at a position other than 0° prior to closing the circuit breaker. This indicates ___________. A. the frequency of ... be closed after breaker has been reset D. there is an existing cross current between generators
Description : The RPM of an AC generator can be measured with a/an _____________. A. ammeter B. voltmeter C. vibrating reed meter D. synchroscope
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
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 : When paralleling two alternators the synchronizing lamps grow dim and are totally darkened as the synchroscope pointer approaches the 0° position. This indicates the ____________. A. alternator voltages ... alternator is in phase with the bus voltage D. synchroscope pointer is defective or broken
Description : When paralleling two alternators, the synchronizing lamps remain lit as the synchroscope pointer approaches the 0°. This indicates the _____________. A. incoming alternator is running too fast B. alternator ... apart C. synchroscope is defective or broken D. alternator power factors are in phase
Description : An AC generator panel is fitted with both synchronizing lamps and a synchroscope. When the synchroscope pointer reaches the noon position, one synchronizing light is bright and the other is dark. This ... sequence is incorrect C. the phase sequence is correct D. the generator breaker may be closed
Description : When paralleling two alternators using three synchronizing lamps, the flickering of all three lamps becomes progressively slower and slower. This means the ______________. A. frequency of the incoming ... the bus D. terminal voltage of the incoming alternator is approaching that of the bus
Description : An alternator switchboard has a synchroscope and synchronizing lamps. If the synchroscope is broken, which of the steps listed is the most essential before an alternator can be paralleled with the bus? ... D. A portable phase sequence indicator must be used to verify the information from the lamps.
Description : Prior to starting an AC generator prime mover, the voltage regulator cutout switch should be placed in the __________. A. manual position B. bus neutral position C. raise voltage position D. transfer position
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 : When two AC generators are being paralleled, the breaker should be closed with the synchroscope pointer rotating in the ____________. A. 'slow' direction, just before the 12 o'clock position B. 'fast' ... just before the 12 o'clock position D. 'slow' direction, just after the 12 o'clock position
Description : You are paralleling two alternators. The synchronizing lamps grow dim and are totally darkened as the synchroscope pointer approaches the 0° position. This indicates that the ____________. A. alternator ... be closed C. incoming alternator is running too slowly D. synchroscope is defective or broken
Description : An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. ... between the armature and the bus D. cause high currents to be induced in the field windings
Description : Automatic voltage regulators provided on switchboards function to _____________. A. regulate the AC load on the generator B. protect the switchboard from high voltage C. govern prime mover speed to control voltage D. vary the field excitation to the generators
Description : The power factor at which a paralleled AC generator operates is usually adjusted by the _____________. A. connected load B. prime mover speed C. field excitation D. generator's rated voltage
Description : If the steering stand selector switch is allowed to remain in the 'Non-Followup' mode after testing of the steering gear, the rudder will _____________. EL-0097 A. not respond to commands from the ... actuator D. stop moving only when the helm is counter-rotated to put the pump at neutral stroke
Description : In order to safely carry out repairs to a generator circuit breaker, it must be isolated from the bus. This is accomplished by opening the _____________. A. reverse power relay B. bus disconnect link C. generator bus fuse connections D. power directional relay
Description : A reverse-current relay will prevent AC generator motorization by ____________. A. automatically redirecting the load B. automatically speeding up the prime mover C. tripping the panel board main switch D. tripping the generator circuit breaker
Description : Regarding an AC generator connected to the main electrical bus; as the electric load and power factor vary, a corresponding change is reflected in the generator armature reaction. These changes in ... . governor speed droop setting B. voltage regulator C. balance coil D. phase-balance relay
Description : Upon failure of the normal power supply, the emergency generator is placed on the line by the _____________. A. bus tie feeder B. automatic bus transfer device C. line connection feeder D. power failure alarm bus
Description : Upon failure of the normal power supply, the emergency generator is placed on the line by the _____________. A. main bus tie feeder B. automatic bus transfer device C. line connection feeder D. power failure alarm bus
Description : A constant output voltage from an AC generator is maintained by the _____________. A. prime mover governor B. exciter generator C. voltage regulator D. reverse power relay
Description : Two AC generators of the same capacity are operating in parallel. One with a zero speed droop setting and the other with a 5% speed droop. If its capacity is not exceeded, the unit whose ... B. maintain the frequency of the system C. have poor sensitivity characteristics D. have poor power response
Description : Transformers are used onboard ships with AC generators to _____________. A. change frequency B. increase power output to modulating frequency controllers C. decrease power output to modulating frequency ... D. permit higher voltage for electric motor operation and low voltage for lighting circuits
Description : If reading the AC voltage from the line lead of a 440 VAC controller the range switch illustrated should be set to ___________. EL-0047 A. 1,000 V B. 250 V C. R X 10,000 D. Unable to safely read with this meter.
Description : The voltage of an operating AC turbogenerator is raised or lowered by adjusting the _____________. A. exciter generator governor controls B. synchronizing switch C. phase sequence switch D. generator field exciter
Description : As shown in the illustration, the function of the switch labeled 'PFSW' is to determine the ______________. EL-0003 A. bus frequency B. reactive volt amperes of the bus C. frequency of either generator D. power factor of either generator
Description : The timer element found in a reverse power relay obtains its operating torque via _____________. A. line voltage B. the main bus C. electromagnets D. a separate battery source
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 : The frequency of an alternator is controlled from the main switchboard by adjusting the _____________. A. frequency meter B. voltage regulator C. governor control D. sychroscope switch
Description : Diesel generators #1 and #2 are operating in parallel at near full load capacity. Diesel generator #1 suddenly trips out mechanically due to low lube oil pressure. The reverse power relay functions ... all nonvital circuits. D. Secure alarms, reset reverse power relay, and restart #1 engine.
Description : The operating torque of the upper induction disc-type element, or timer element, of an AC reverse power relay is obtained from ____________. A. the main bus B. a separate battery source C. line voltage D. electromagnets
Description : The division of the reactive KVA load between paralleled AC generators is initiated by the ______________. A. prime mover governors B. voltage regulators C. phase balance relay D. proportioner
Description : The frequency of an AC generator is controlled by the _____________. A. rheostat B. governor C. exciter D. capacitor
Description : When two generators are on the line and are sharing the load equally, they are said to be operating in _____________. A. frequency B. series C. parallel D. resonance
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 shore power circuit breaker should be closed only _____________. A. when the ship's generators have been directly paralleled to those on shore B. in a shipyard C. if a quick disconnect coupling is used D. when the ship's generators have been removed from the bus