Description : The set point current at which a magnetic-type overload relay tends to trip may be increased by turning the dashpot in the 'lower' direction. This action _____________. A. reduces magnetic force on ... the relay D. increases magnetic force on the plunger and requires less current to trip the relay
Last Answer : Answer: A
Description : A three-phase, induction-type motor experiences an open in one phase. Which of the listed automatic protective devices will prevent the machine from being damaged? A. Overspeed trip B. Thermal overload relay C. Three-pole safety switch D. Magnetic blowout coil
Last Answer : Answer: B
Description : Fuses placed in series with a thermal trip-type circuit breaker are used for _____________. A. time-delay protection B. short-circuit protection C. short duration surge protection D. sustained overload protection
Description : The current at which a magnetic-type overload relay tends to trip may be decreased by raising the plunger further into the magnetic circuit of the relay. This action ___________. A. reduces magnetic ... the relay D. increases magnetic pull on the plunger and requires less current to trip the relay
Last Answer : Answer: D
Description : How will a molded-case circuit breaker react after it has tripped, as a result of an overloaded circuit? A. The breaker will trip again if immediately reset. B. The breaker handle will lock in ... down. D. The breaker handle cannot be moved to the OFF position until the thermal element cools down.
Description : A loss of field excitation to an AC generator while operating in parallel will cause it to ____________. A. absorb more and more load due to decreased armature reaction B. lose its load due to ... polarity D. lose its load, begin to motorize, trip out on reverse power relay, and possibly overspeed
Description : As a result of a mechanical malfunction in one of the ship's service generators operating in parallel, you must secure that generator. In order to prevent a possible overload to the ... feeder circuit breakers, the malfunctioning prime mover turbine throttle trip, and the generator circuit breaker.
Description : Component F in the illustrated device is for _________. EL-0033 A. short circut protection B. latching the trip unit closed after resetting the breaker C. overload protection D. providing a flexible connection between the input terminal G and the tripping unit E
Last Answer : Answer: C
Description : The purpose of the reverse power relay, provided on a ship's service alternator panel, is to trip the circuit in the event of ______________. A. main circuit overload B. high power transfer C. generator overspeeding D. alternator motorization
Description : When power is restored after a complete power failure, a steering gear pump motor will ____________. A. have to be restarted B. have to be reset C. restart automatically D. trip its overload relays
Description : As shown in the illustration, 'S' is the __________. EL-0017 A. safety switch B. overload trip C. start button D. stop button
Description : The arc resulting from the tripping of a circuit breaker is prevented from damaging the contacts by _____________. A. designing the contacts to open slowly B. directing the arc into an ... an inverse timed thermal trip for short circuit currents D. instantaneous magnetic trip for overload currents
Description : The purpose of a main switchboard circuit breaker's reverse-power trip is to _____________. A. prevent main circuit overload B. protect the circuit breaker blowout coil C. prevent alternator motorization D. prevent low voltage tripout
Description : Protection against sustained overloads occurring in molded-case circuit breakers is provided by a/an __________. A. overvoltage release B. thermal acting trip C. thermal overload relay D. current overload relay
Description : How is an overload condition indicated by the electronic digital multimeter?
Last Answer : Simultaneous flashing of display readouts
Description : During maintenance of circuit breakers, _______________. A. always smooth roughened contact surfaces with a file B. never pass more than rated breaker current through the overload heater element C. ... wear and misalignment of main contacts D. assume heater elements installed are of correct size
Description : An element in electronics which serves as a protection against overload?
Last Answer : fuse
Description : Where should you use a trip-free circuit breaker?
Last Answer : In current sensitive or nonemergency systems.
Description : What is a trip-free circuit breaker?
Last Answer : A circuit breaker that will trip even if the operating mechanism is held ON.
Description : What are the three types of circuit breaker trip elements?
Last Answer : Thermal, magnetic, and thermal-magnetic
Description : How does a capacitor and an inductor react to (a) low frequency and (b) high frequency?
Last Answer : At low-frequency, a capacitor acts as an open and an inductor acts as a short. At high-frequency, a capacitor acts as a short and an inductor acts as an open.
Description : What value does a meter movement react to (actually measure) when measuring ac?
Last Answer : Average value.
Description : How would the compass react if the alternating current through the conductor was a high frequency?
Last Answer : The compass needle would vibrate rapidly around the zero current point ac meter (magnetic north).
Description : How would a compass react when placed close to a conductor carrying alternating current at a low frequency?
Last Answer : The compass needle would swing back and forth as the current changed from positive to negative.
Description : How does a compass react when placed close to a current carrying conductor?
Last Answer : The compass needle swings away from magnetic north and aligns itself with the magnetic field around the conductor
Description : An instantaneous-trip-type fuse will _____________. A. open as soon as the load current exceeds its set point B. allow a preset delay between overcurrent and melting C. open a circuit by using a time delay element with a magnetic trip D. reset itself when the overcurrent is corrected
Description : In accordance with Coast Guard Regulations (46 CFR), a circuit breaker located in the machinery space and installed in a 440V AC system must _____________. A. be dependent upon mechanical ... the maximum asymmetrical shortcircuit current available at the point of application D. all of the above
Description : If current gain is required from an rf amplifier, what type of component should be used as an output coupling element?
Last Answer : A step-down transformer.
Description : What type of tube best meets the requirements of a modulator switching element?
Last Answer : Thyratron.
Description : The type of control circuit that will not permit automatic restarting after power is restored, following a power failure is called _____________. A. low voltage protection B. low voltage release C. overload lockout D. reduced voltage restart
Description : Overload relays are of...... type. (a) induction (b) solid state (c) thermal (d) electromagnetic (e) all above
Last Answer : (e) all above
Description : What element will most likely react in a similar way as fluorine?
Last Answer : Need answer
Description : Which type of graph would you use to show the number of students who went on the field trip and the number of students who did not go on the field trip in each class?
Last Answer : losers
Description : What element is controlled to focus the beam?
Last Answer : The first anode.
Description : What element controls the number of electrons striking the screen?
Last Answer : Control grid.
Description : In applications where electronic waveforms are displayed on a CRT screen, the input signal is normally applied to what CRT element?
Last Answer : The vertical-deflection plate.
Description : The electron beam in a CRT is made to sweep from left to right across the screen. What tube element causes this sweeping motion?
Last Answer : The horizontal-deflection plate.
Description : Beam-forming tubes and power tubes are similar except that power pentodes lack what element?
Last Answer : Beam-forming plates.
Description : A, what logic element enables FF3 to toggle with the clock?
Last Answer : The AND gate
Description : . In a MOSFET, which element is insulated from the channel material?
Last Answer : The gate terminal.
Description : The base of a transistor serves a purpose similar to what element of the FET
Last Answer : Gate.
Description : . In a common anode, seven-segment LED display, an individual LED will light if a negative voltage is applied to what element?
Last Answer : The cathode.
Description : What is the fundamental element in program preparation?
Last Answer : The instruction.
Description : What is the smallest particle into which an element can be broken down and still retain all its original properties?
Last Answer : The atom.
Description : What modulator element controls the rate at which the storage element charges?
Last Answer : The charging impedance.
Description : What element in the magnetron causes the curved path of electron flow?
Last Answer : The permanent magnet.
Description : What element of the reflex klystron replaces the output cavity of a normal klystron?
Last Answer : The reflector or repeller.