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
Last Answer : Answer: A
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
Last Answer : Answer: B
Description : As shown in the illustration, which listed action will occur first when push button 'Q' is depressed? EL-0017 A. Contacts 'H-1', 'H-2' and 'H-3' close. B. Contact 'H-4' closes. C. Operating coil 'C' energizes. D. Switch 'R' opens.
Last Answer : Answer: C
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.
Last Answer : Answer: D
Description : When an operating motor is connected to the controller shown in the illustration, the a path of current flow through the circuit is ____________. EL-0010 A. 'L1', stop button, start button, coil 'CR', 'L2' B. 'L1' ... L2' D. 'L1', stop button, start button, 'CR' contact, 'M' contact, 'CR' coil, 'L2'
Description : In the illustrated motor controller, the motor fails to start. A voltmeter reading between 1 and 6 reads line voltage, while the voltmeter reading between 2 and 6 reads 0 VAC. The problem is __________. EL- ... in the 'M' coil, 'Ma' contact/start switch or overload contacts D. fuse '10a' is blown
Description : To stop the electric motor shown in the illustration, the stop button is depressed, causing ____________. EL-0012 A. coil 'MS' to become de-energized B. contacts 'CR1' and 'MR4' to open C. contacts 'MR1', 'MR2', and 'MR3' to open D. contacts 'MS1', 'MS2', and 'MS3' to open
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 : As shown in the illustration, the symbol is used in electrical drawings to designate a ____________. EL-0026 A. limit switch with one set of normally open contacts B. maintaining type ... type push button with a mechanical interlock D. normally closed contact held open mechanically by an interlock
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 : 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 : If the motor shown in the illustration will not start when 'Q' is depressed, which of the listed components should be checked FIRST? EL-0017 A. Fuses 'F-1' and 'F-2'. B. Operating coil 'C'. C. Contacts 'H-1', 'H-2', and 'H-3'. D. Contact 'H-4'.
Description : If the motor fails to start and a voltmeter reading between 1 and 6, as illustrated, indicates line voltage, your next step should be to ________. EL-0007 A. replace fuse '10a' B. replace or repair contact 'Ma' C. reset and determine the cause of the overload D. check line voltage between L1 and L3
Description : If 450 volts AC were measured across the load as shown in the illustration it would indicate a/an _______________. EL-0083 A. open winding between 'H1' and 'X1' B. properly operating circuit C. open winding between 'X1' and 'X4' D. ground on one side of 'Ep'
Description : The winch shown in the illustration operates in any of the positions with the master switch in the 'lower' direction, but will not 'hoist' in any of the master switch hoist positions. Which of the listed faults ... '2M' in the power circuit may be badly corroded. D. Series relay 'FR' may be open.
Description : When the master switch for the winch shown in the illustration is in the 'off' position, and the line & safe switches are closed, which of the listed relays should be energized? EL-0102 A. 'DB' & '2T' B. 'DB' & '4M' C. 'FR-B.O.' & 'LV' D. '1M' & '1A'
Description : When the series field relay "FR" of the winch circuit shown in the illustration is energized during dynamic braking the _______________. EL-0102 A. shunt Field Relay "FR-B.O." is de-energized and contacts ... . shunt Field Relay "FR-B.O." opposes the series coil's flux and sets the mechanical brake
Description : As shown in the illustration, 'H1' and 'H2' are ___________. EL-0058 A. fixed capacitors B. variable capacitors C. contacts, closed when the circuit is energized D. contacts, open when the circuit is energized
Description : The wiring diagram for the motor starting circuit shown in the illustration indicates ______________. EL-0007 A. resistance starting B. reduced voltage starting C. low voltage protection D. low voltage release
Description : You are performing an out-of-circuit test of the semi-conductor shown in the illustration. Using an ohmmeter on 'low power' position and with leads properly installed, which of the listed results would you expect the ... lead on 'B' and black lead on 'A'; and a low reading with the leads reversed.
Description : You are performing an out-of-circuit test of the semi-conductor shown in the illustration. Using an ohmmeter on 'low power' position and with leads properly installed, which of the listed results would indicate a good ... lead on 'A' and red lead on 'C'; and a high reading with the leads reversed.
Description : You are performing an out-of-circuit test on the semi-conductor shown in the illustration. Using an ohmmeter on 'low power' setting and with leads properly inserted, which of the listed results would indicate a good ... lead on 'A' and red lead on 'C'; and a high reading with the leads reversed.
Description : As shown in the illustration, what is responsible for maintaining the "LV" relay energized when the master switch handle is moved away from the "off" position? EL-0102 A. "DBa" contact. B. Reset contacts. C. Upper set of "LVa" contacts. D. Lower set of "LVa" contacts.
Description : As shown in the illustration, once the "LV" relay is energized for operation, what contacts must remain closed to maintain the "LV" relay energized when the control lever is moved away from the "off" or "stop" ... . B. Reset contacts. C. Upper set of "LVa" contacts. D. Lower set of "LVa" contacts.
Description : As shown in the illustration, 'S' is the __________. EL-0017 A. safety switch B. overload trip C. start button D. stop button
Description : Which of the listed electrical devices is represented by the symbol shown in the illustration? EL-0055 A. Fixed resistance resistor B. Coil with magnetic core C. DC motor or generator shunt field D. Transformer
Description : Which of the devices listed is indicated by the electronic symbol lettered as 'A', shown in the illustration? EL-0016 A. Thyristor B. Diode C. Capacitor D. Transistor
Description : Which of the devices listed is indicated by the symbols lettered 'A' to 'F', shown in the illustration? EL-0016 A. Diodes B. Linear inductors C. Capacitors D. Transistors
Description : Which of the listed figures shown in the illustration represents devices connected in a three-phase delta-delta arrangement? EL-0084 A. A B. B C. C D. D
Description : Due to its construction, the component in figure 'A' shown in the illustration has which of the listed advantages compared to bipolar devices? EL-0078 A. Operates with higher voltages and ... as a controllable rectifier. D. Has very high input resistance and uses practically no gate current.
Description : Which of the listed figures shown in the illustration represents devices connected in a three-phase delta-wye arrangement? EL-0084 A. A B. B C. C D. D
Description : Which of the listed figures shown in the illustration represents devices connected in a three-phase wye-delta arrangement? EL-0084 A. A B. B C. C D. D
Description : Which of the listed figures shown in the illustration represents devices connected in a three-phase wye-wye arrangement? EL-0084 A. A B. B C. C D. D
Description : In order to prevent the winch shown in the illustration from turning while troubleshooting the controller circuit, _________________. EL-0102 A. set the dynamic brake by clamping contact 'DB' closed B. set the ... at 'B1' and 'B2' D. open the test link preventing current flow to the armature
Description : During start-up of the circuit shown in the illustration, it is noted that the ends of component 'C' alternately glow and become dark without the tube illuminating. The most probable cause ... start the lamp D. component 'B' contacts are opening and closing thus prohibiting sufficient current flow
Description : The devices marked 'T' in the illustration are _____________. EL-0080 A. trouble alarm units whose contacts activate when problems arise either on starting or stopping of the motor B. topping ... contactor parts whose contacts start and stop the defrosting cycle of the compressor driven by the motor
Description : In an emergency, the fastest way to interrupt power and stop the winch shown in the illustration is for the ____________. EL-0102 A. mate to open the disconnect switch at 'L1' and 'L2' B. ... watch engineer to open the winch circuit breaker D. electrician to open the test link at the controller
Description : Which of the devices shown in the illustration automatically prevents the simultaneous operation of the windlass from both master switches? EL-0073 A. Selector switch B. Contact 'CR1a' C. Contact 'CR2a' D. Contact 'CR1D'
Description : Erratic operation of the devices represented in the diagrams shown in the illustration could be traced to ____________. EL-0092 A. improper contact at 'R' slip rings or 'S' connections B. a low three- ... . improper contact at 'S' slip rings or 'R' connections D. a high three-phase voltage supply
Description : Which of the illustrations listed below is representative of a motor controller's 'schematic' or 'elementary' diagram? A. EL-0023 B. EL-0007 C. EL-0037 D. EL-0058
Description : During the start-up of the circuit shown in the illustration, it is noted that the ends of component 'C' remain lighted but the tube does not illuminate. The cause of this problem is ____________. EL- ... ' is closed C. component 'C' is the wrong wattage D. component 'B' contacts are stuck closed
Description : The main difference between a motor control circuit containing low voltage protection and low voltage release is that the latter contains _____________. A. a magnetic operating coil B. normally open line contacts C. thermal-overload protection D. a momentary-contact start button
Description : In the illustration, the tan and white wires are connected to the solenoid valve. The solinoid valve is_________. EL-0043 A. in the liquid line before the TXV B. energized and open whenever the unit ... so the unit must be modified before using aboard ship D. the water inlet for the ice maker
Description : In the illustration, the tan and white wires are connected to the solenoid valve. The solenoid valve is_________. EL-0042 A. in the liquid line before the TXV B. energized and open whenever the unit ... so the unit must be modified before using aboard ship D. the water inlet for the ice maker
Description : When reading AC current with the multimeter shown in the illustration and you are unsure of the range, the range switch should be set to ___________. EL-0047 A. 10 MA/ 10 AMP with leads in the (-10 A ... leads in the (-COMMON) and (+10 A) jacks D. unable to measure AC current with this multimeter
Description : The arrow drawn through the component shown in the illustration means that the device's value _____________. EL-0015 A. is fixed and cannot be changed B. is variable between two limits C. has yet to be determined for the circuit application D. is not allowed to change during circuit operation
Description : The three devices which make up the circuit shown in the illustration are ____________. EL-0087 A. flip-flops B. exclusive 'OR' gates C. summing op amps D. function generators
Description : In the system shown in the illustration, the station at section I is unable to signal any other station nor is any other station able to signal the station in section I. The station can, however, ring ... only a single station to respond to itself. D. The switch at component 'C' is stuck open.
Description : As shown in the illustration, what happens when 'A' is closed, 'B' is in position '2' and component 'E2' burns out? EL-0058 A. 'H' energizes and 'D' makes contact. B. 'F' goes out allowing 'G' to disconnect. C. 'G' sounds an alarm and 'F' illuminates. D. 'C' opens causing 'A' to also open.
Description : The purpose of the 'heater resistors' for the winch circuit shown in the illustration is to _______________. EL-0102 A. limit the current in the heater circuit B. dispel moisture in the ' ... panel C. keep the winch brake housing below the dew point D. maintain winch motor operating temperature