Description : A useful instrument for checking A.C. motor performance by measuring possible unbalanced currents is the _____________. A. hand or battery-operated megger B. vibrating-reed frequency meter C. hook-on voltmeter-ammeter D. D'Arsonval iron-vane probe
Last Answer : Answer: C
Description : When paralleling two AC generators, the synchroscope selector switch and frequency meter switch should be set up to sense the frequency of the _____________. A. bus B. generator on the line C. oncoming generator D. bus transfer relay
Description : An electric tachometer receives the engine speed signal from a _______________. A. small generator mounted on the engine B. bimetallic sensing device C. stroboscopic sensing device D. vibrating reed meter generating a voltage proportionate to engine speed
Last Answer : Answer: A
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
Last Answer : Answer: B
Description : The basic meter movement responds to the flow of current through its coil. Therefore, this meter movement may be used as a/an _____________. A. voltmeter by placing a resistance in parallel with the ... in parallel with the coil D. ammeter by placing a low resistance in parallel with the coil
Last Answer : Answer: D
Description : Conductor resistance may be INDIRECTLY measured by using a/an _____________. A. voltmeter only B. ammeter only C. voltmeter and an ammeter D. ohmmeter only
Description : An internal resistance is placed in series with the meter movement of which of the following instruments? A. AC ammeter B. DC ammeter C. DC voltmeter D. Frequency meter
Description : A switchboard, for a AC electrical distribution system, will be provided with which of the following components? A. Frequency meter. B. Ammeter C. Voltmeter D. All of the above
Description : If the approximate voltage to be measured in a circuit is not known, you should _____________. A. use the lowest voltage range on the voltmeter B. connect the meter in series with the circuit C. only have to calibrate the meter before using it D. use the highest voltage range on the voltmeter
Description : An AC generator produces 60 Hz at 1800 RPM. If the generator speed is increased to 1830 RPM, the cycles will _____________. A. remain at 60 Hz B. increase to 61 Hz C. decrease to 59 Hz D. increase to 63 Hz
Description : Type of power-line frequency meter composed of vibrating iron reed placed in alternating magnetic field
Last Answer : Vibrating Reed Type
Last Answer : In a vibrating reed frequency meter the natural frequencies of two adjacent reeds have a difference of 0.5 Hz.
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
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 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 : 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
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 : Which of the following meters uses a shunt connected in series with the load, but parallel with the meter movement? A. voltmeter B. power factor meter C. wattmeter D. ammeter
Description : Which of the listed meters uses a shunt connected in series with the load, but parallel with the meter movement? A. Voltmeter B. Power factor meter C. Ammeter D. Wattmeter
Description : In order to increase its range of measurement, a resistance would be placed in series with which of the following instruments? A. DC voltmeter B. DC ammeter C. frequency meter D. power factor meter
Description : A multimeter may be damaged by taking a _____________. A. voltage reading while in the ammeter mode B. current reading while in the voltmeter mode C. resistance reading while in the ammeter mode D. resistance reading while in the voltmeter mode
Description : You are calibrating a multimeter using internal batteries to supply power for resistance measurements. However, you are unable to adjust the pointer to 'zero' using the adjustment knob. Therefore, you should ... change scales to the R X 100 scale and adjust using the 'zero ohms' adjusting knob
Description : To determine the state of charge of a nickel-cadmium battery, you would use a/an _____________. A. voltmeter B. hydrometer C. ammeter D. potentiometer
Description : A resistance in a circuit of unknown value is to be tested using the voltmeter/ammeter method. Therefore, the meters should be connected with _____________. A. both meters in series with the ... parallel with the resistance D. the ammeter in parallel and the voltmeter in series with the resistance
Description : Component 'D' in section 'I' shown in the illustration represents a ____________. EL-0093 A. selector switch B. vibrating reed indicator C. junction box D. ring counter
Description : The conversion of the throttle command voltage to the signal necessary to achieve the desired shaft RPM is accomplished by the _____________. A. ahead or astern function generator of the ... circuit C. operational amplifiers in the autorotation circuit D. long time constant amplifier circuit
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
Description : A switchboard ammeter indicates a reading slightly above 'zero' when the leads are disconnected, this is caused by _____________. A. mechanical misalignment of the meter pointer B. a poor ground for the meter case C. static electricity in the air D. capacitors inside the meter storing charges
Description : The most practical method of controlling the RPM of a step-speed AC motor is to _____________. A. change input voltage B. vary the number of poles C. vary power factor D. change the number of brushes
Description : The prime mover of an AC two pole main propulsion generator drives the generator at 3600 RPM. If the main propulsion motor has 80 poles, what will be the propeller speed? A. 45 RPM B. 80 RPM C. 90 RPM D. 180 RPM
Description : The hook-on AC volt-ammeter consists essentially of a split-core and a rectifiertype instrument connected to the secondary winding of a _____________. A. potential transformer B. control transformer C. current transformer D. reactance transformer
Description : What are the physical quantities measured with voltmeter and ammeter ?
Last Answer : : The voltage difference between two points of a circuit is measured with a voltmeter. And the flow rate of an electric circuit is measured with an ammeter.
Description : Electric current is measured by (1) Voltmeter (2) Anemometer (3) Commutator (4) Ammeter
Last Answer : (4) Ammeter
Description : Electric current is measured using which of the following instrument ? (1) Ammeter (2) Voltmeter (3) Anemometer (4) Wattmeter
Last Answer : Ammeter
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 : 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 : If the pointer of the synchroscope is rotating in the slow direction when you are preparing to parallel two alternators, the _____________. A. incoming machine is turning faster than the load alternator B ... alternator is ready to split D. incoming machine is beginning to pick up some of the load
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 : 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 : 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 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 : Which of the instruments listed should always be connected in series with a circuit? A. Ammeter B. Megohmmeter C. Wattmeter D. Voltmeter
Description : To test the state of charge of a nickel-cadmium battery, you should use a/an ____________. A. ammeter B. voltmeter C. hydrometer D. potentiometer
Description : In preparing to take insulation resistance readings on a main generator, the windings should be grounded for about 15 minutes prior to the test to _____________. A. allow accurate zeroing of the meter ... the windings D. help the windings to cool to the same temperature as the ground test connection
Description : A faulty 'function generator' shown in the illustration may prevent _____________. EL-0095 A. proper pitch control from both the 'bridge' and 'engine room thrust levers' B. the 'split potentiometer ... control pitch C. the pitch meter from indicating accurately D. relays #2 and/or #3 from energizing
Description : On some electrical generating equipment one outboard bearing pedestal is insulated from the bedplate. This should be checked with a millivolt meter and a jumper. With the millivolt meter connectd between ... then removed to take a second reading. This eliminates the insulating effect of the bearing.
Description : When measuring AC current flow, you must always connect the meter _____________. A. in series with the power source and load B. in parallel with the power source and load C. insuring correct polarity D. using the lowest range possible to prevent instrument damage
Description : A testing device called a 'growler' is being used to locate a shorted coil in the stator of an AC electrical machine. When the 'feeler' is moved over a slot containing the shorted coil _____________. ... . the meter needle will be deflected to zero D. the meter needle will be deflected to full-scale
Description : The most common type of AC service generator found aboard ship is the stationary _____________. A. electromagnetic field, revolving armature type B. electromagnetic field, oscillatory armature type C. armature, oscillatory electromagnet field type D. armature, rotating electromagnetic field type