Year 3 IEC |ACCURATE QUESTIONS |VERIFIED ANSWERS | LATEST UPDATE |NEW VERSION 2024- 2025, Exams of Electrical and Electronics Engineering

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Year 3 IEC |ACCURATE QUESTIONS

|VERIFIED ANSWERS | LATEST UPDATE

|NEW VERSION 2024-

2025|GUARANTEED PASS|

Storage areas shall be kept free from accumulation of ___ that constitute hazards from tripping, fire, explosion, or pest harborage. Select one: a.5' stacks of lumber b.lunch trash c.4' brick stacks d.all of these

• ANSWER b. lunch trash All scrap lumber, waste material and rubbish shall be removed from the work area as work progresses. Select one: a.True b.False
• ANSWER a. True Maximum safe load limits of floors within buildings and structures, in pounds per square foot, shall be ___. Select one: a.recorded in the HazCom Manual b.conspicuously posted c.measured daily
• ANSWER b. conspicuously posted OSHA regulation CFR1926.250 covers materials handling ___. I. storage II. use III. disposal Select one: a.I only b.I, II & III c.III only

d.II only

• ANSWER b. I, II & III A manual reversing starter is an assembly that includes ___ and a mechanical interlock. I. 2 contactors II. 2 OL sections III. 1 contactor IV. 1 OL section Select one: a.I & II b.II & III c.I & IV d.III & IV
  • ANSWER c. I & IV A manual reversing starter requires ___ OL section(s). Select one: a.one b.two
• ANSWER a. one Internal drum switch connections are made between terminals 5 and 6 when the switch is in the ___ position. Select one: a.Forward b.Reverse c.both a and b d.neither a nor b
  • ANSWER c. both a and b Refer to Figure 331.11. The coils on the reversing starter are rated for ___ volts. Select one: a. b. c. d. e.
  • ANSWER b. 120 The control switching for a reversing starter can consist of ___.

Select one: a.a stop PB, a start PB, and a forward/reverse selector switch b.a stop PB, a forward PB, and a reverse PB c.either a or b d.neither a nor b

• ANSWER c. either a or b The industry standard method used to reverse the rotation of a 1Ø AC motor is to use a reversing starter to change the current flow direction through the ___ winding. Select one: a.start b.run
• ANSWER a. start The industry standard method used to reverse the rotation of a DC motor is to use a reversing starter to change the current flow direction through the ___ winding. Select one: a.field b.armature
• ANSWER b. armature Heavier gauge wire is used for the ___ winding in a 1Ø motor. Select one: a.run b.start
• ANSWER a. run Drum switches have a center off position. Select one: a.True b.False
• ANSWER a. True Drum switches contain OL protection. Select one: a.True b.False
• ANSWER b. False Drum switches are considered to be ___.

Select one: a.starters b.controllers c.both a and b

• ANSWER b. controllers Which of the following correctly show the internal switching diagram for a drum switch? Select one: a. b. c. - ANSWER b. You will use this drum switch to control the direction of a 3Ø garbage disposer motor in the kitchen of a restaurant. Select the correct connections from the possible answers. L1, L2 & L3 are the circuit conductors from the 3-pole breaker in the panel and T1, T2 & T3 are the motor leads. ST = drum switch terminal. Select one: a.L1 to ST 1; T1 to ST 2; L2 to ST 3; T2 to ST 4; L3 to ST 5; & T3 to ST 6 b.L1 to ST 1; T1 to ST 3; L2 to ST 2; T2 to ST 4; L3 to ST 5; & T3 to ST 6 c.L1 to ST 1; T1 to ST 4; L2 to ST 2; T2 to ST 3; L3 to ST 5 & T3 to ST 6 d.L1 to ST 1; T1 to ST 3; L2 to ST 4; T2 to ST 2; L3 to ST 5; & T3 to ST 6
• ANSWER d. L1 to ST 1; T1 to ST 3; L2 to ST 4; T2 to ST 2; L3 to ST 5; & T3 to ST 6 Motors that are to be forward- and reverse-operated can be prevented from attempting to do both simultaneously by which of the following methods? Select one: a.By using mechanically interlocked forward-reverse pushbutton switches b.By using two separate motor starters with one NO and one NC set of contacts on each starter c.By using one mechanically interlocked reversing starter d.Any of these methods will work e.None of these methods will work
• ANSWER d. Any of these methods will work The use of mechanically-interlocked, magnetic reversing starters is indicated on a ladder diagram by ___. Select one: a.dashed lines between the coils b.crossing dashed lines between the two NO PB switches c.either a or b d.neither a nor b
• ANSWER a. dashed lines between the coils

Where momentary contact switching is used, which of these line diagrams is correct for electrical interlocking of a reversible motor circuit? A single reversing starter is used. Select one: a. b. c. d.

• ANSWER b. Refer to Figure 331.12. Terminal K on the starter could be used as point ___ on the diagram. Select one: a. b. c.L d. e.
• ANSWER e. 12 Refer to Figure 331.12. Point ___ on the starter could be used to connect as Point 5 on the diagram. Select one: a.J b.L c.T d.Q e.N
• ANSWER e. N Refer to Figure 331.14. Point ___ on the starter could be used to connect as Point 10 on the diagram. Select one: a.L b.J c.S d.R e.YY
• ANSWER c. S Refer to Figure 331.14. Point ___ on the starter could be used to connect as Point 11 on the diagram.

Select one: a.I b.N c.V d.Q e.XX

• ANSWER d. Q Refer to Figure 331.14. Point ___ on the starter could be used to connect as Point 8 on the diagram. Select one: a.I b.N c.V d.Q e.XX
  • ANSWER b. N Refer to Figure 331.15. The jumper shown between Points 9 & 10 on the ladder would be connected between Terminals ___ on the starter. Select one: a.Q & X b.W & V c.Z & W d.X & S e.S & O
  • ANSWER a. Q & X Refer to Figure 331.15. The jumper shown between Points 11 & 6 on the ladder would be connected between Terminals ___ on the starter. Select one: a.V & Q b.W & O c.Y & S d.X & P e.V & M
• ANSWER c. Y & S For a reversing starter control circuit, indicating lights can be used to indicate ___. Select one: a.direction of motor rotation

b.presence of control circuit power c.either a or b d.neither a nor b

• ANSWER c. either a or b Limit switches can be used in a reversing starter control circuit to provide ___. Select one: a.automatic control b.overtravel protection c.either a or b d.neither a nor b
  • ANSWER c. either a or b Highway construction fatalities rarely include instances of workers being struck by moving vehicles. Select one: a.True b.False
• ANSWER b. False Between 2003-2017 there were ___ deaths in highway construction in the U.S. Select one: a.1, b.66, c.131, d.1,
  • ANSWER d. 1, Over a period of recent years, there has been a(n) ___ in the number of highway construction projects. Select one: a.decrease b.increase
  • ANSWER b. increase On road construction projects, flaggers must wear vests that are ___ any barricades. Select one: a.the same color as b.a different color than
  • ANSWER b. a different color than

When the public drives past a highway construction project, these drivers pose no danger to the construction workers. Select one: a.True b.False

• ANSWER b. False Highway safety data indicates that roadway construction workers are killed at a rate nearly ___ times the rate of other forms of construction. Select one: a.twelve b.three c.twenty d.one hundred - ANSWER b. three Refer to Figure 333.1. Point 33 on the ladder diagram is Terminal ___ on the relay. Select one: a.A b.B c. d. e.4 - ANSWER b. B Another term for an alternating relay is a ___ relay. Select one: a.impulse b.flip-flop c.either a or b d.neither a nor b - ANSWER c. either a or b ___ is the starting of a motor for short periods of time and is generally used for positioning of a driven load. Select one: a.plugging b.sequencing c.braking d.jogging - ANSWER d. jogging Phase unbalance in a three-phase system causes ___. Select one:

a.phase shifting b.overheated motors c.both a and b d.neither a nor b - ANSWER c. both a and b In a three-phase system, a voltage unbalance greater than ___ from the average voltage should be investigated. Select one: a.7.2 volts b.2 percent c.3.6 volts d.5 percent - ANSWER b. 2 percent Although a phase failure relay would be the optimal choice to protect a motor from overheating when a phase failure occurs, some motors have some protection provided by ___. Select one: a.inherent OL protectors b.properly sized OL protection in the starter c.either a or b - ANSWER c. either a or b Many job specifications require phase-reversal protection for three-phase motors operating ___. Select one: a.escalators b.ski lifts c.elevators d.all of these - ANSWER d. all of these ___ is the frequent starting and stopping of a motor for short periods of time. Select one: a.Interfacing b.Breakover c.Jogging d.Positioning e.Interlocking - ANSWER c. Jogging The frequent starting and stopping of a motor for short periods of time is ___. Select one: a.Positioning b.Interfacing

c.Breakover d.Interlocking e.Jogging - ANSWER e. Jogging A(n) ___ circuit allows the operator to start and run a motor for short periods of time without memory. Select one: a.reversing b.momentary c.jogging d.interlock - ANSWER c. jogging The common feature of all jog circuits is that they prevent the ___ from operating. Select one: a.holding circuit b.motor c.stop pushbutton switch d.starter overloads - ANSWER a. holding circuit Refer to Figure 333.11. The connections shown in Diagram ___ will permit the motor to be either started or jogged into position. Select one: a.II only b.I & II only c.I only d.II & III only e.I, II & III - ANSWER e. I, II & III Refer to Figure 333.11. The connections shown in Diagram II will permit the motor to be ___. Select one: a.jogged into position b.started c.either a or b d.neither a nor b - ANSWER c. either a or b Refer to Figure 333.11. The connections shown in Diagram III will permit the motor to be ___. Select one: a.jogged into position b.started

c.either a or b d.neither a nor b - ANSWER c. either a or b For motor controls, another term used for jogging is ___. Select one: a.interlocking b.sequencing c.breakover d.inching - ANSWER d. inching Of the two types listed, a(n) ___ held relay operates more quietly. Select one: a.electrically b.mechanically - ANSWER b. mechanically To operate a latching relay, ___ power is applied. Select one: a.momentary b.constant - ANSWER a. momentary A contactor, that closes when power is applied to one coil and releases only when power is applied to a second coil, is referred to as ___ held. Select one: a.electrically b.mechanically - ANSWER b. mechanically Refer to Figure 333.1. Point 34 on the ladder diagram is Terminal ___ on the relay. Select one: a.A b.B c. d. e.7 - ANSWER a. A Refer to Figure 333.1. Point 11 on the ladder diagram is Terminal ___ on the relay. Select one: a.A b.B c. d.

e.8 - ANSWER d. 4 Refer to Figure 333.1. After Sw 1 has been pushed and released the red light will be ___. Select one: a.ON b.OFF - ANSWER b. OFF Refer to Figure 333.1. Both the red and the green lights will be ON ___. Select one: a.when Sw 1 and then Sw 2 are pushed b.when Sw 2 and then Sw 1 are pushed c.when the control power is OFF d.never - ANSWER d. never Refer to Figure 333.1. After Sw 2 has been pushed and released, the red light will be ___. Select one: a.OFF b.ON - ANSWER b. ON Refer to Figure 333.1. The control circuit neutral can be connected to relay terminal ___ without damaging the relay. Select one: a.either A or B b.either 8 or B c.8 only d.A only e.B only - ANSWER e. B only XX For the Siemens relay shown in Figure 333.3, Point 7 on the ladder diagram must be connected to pin ___ on the relay base. Select one: a. b. c.A d.B e.8 - ANSWER e. 8 For the Siemens relay shown in Figure 333.3, Point 3 on the ladder diagram must be connected to pin ___ on the relay base.

Select one: a. b. c.A d.B e.8 - ANSWER d. B For the Siemens relay shown in Figure 333.3, Point 4 on the ladder diagram must be connected to pin ___ on the relay base. Select one: a.A b. c. d. e.B - ANSWER a. A Refer to Figure 333.2. When the control circuit power is turned ON, neither M1 nor M is energized. Select one: a.True b.False - ANSWER b. False Refer to Figure 333.2. When the control circuit power is turned ON, ___ is (are) energized. Select one: a.M b.M c.both a and b d.neither a nor b - ANSWER b. M Refer to Figure 333.2. When the control circuit power is turned ON and either PB is pushed and released, ___ is (are) energized. Select one: a.M b.M c.both a and b d.neither a nor b - ANSWER a. M Refer to Figure 333.2. The control circuit power is turned ON and PB 1 is pressed and held closed. M1 is now energized and M2 is de-energized.

Select one: a.False b.True - ANSWER a. False Refer to Figure 333.2. The control circuit power is turned ON and PB 2 is pressed and held closed. M1 is now energized and M2 is de-energized. Select one: a.False b.True - ANSWER a. False Refer to Figure 333.2. The control circuit power is turned ON and PB 1 is pressed and released. Neither M1 nor M2 is energized because there are no holding contacts in the circuit. Select one: a.False b.True - ANSWER a. False Refer to Figure 333.4. Which of the drawings is correctly connected for a darkroom installation? Any film being developed under a red light will be damaged if the door is opened or if the white light is ON inside the room. The pushbutton switch is used to control the operation of the lights and signs. The Do Not Enter warning sign should be illuminated only when developing processes are taking place inside the room under a red light. The Safe To Enter sign should be illuminated only when the white light is ON inside the darkroom. Both warning signs are located outside the darkroom door. Select one: a.I or II or III b.II or III only c.I or III only d.II only e.III only - ANSWER e. III only Refer to Figure 333.20. Points 13 & 14 on the ladder diagram could be connected to terminals ___ on the impulse relay. Select one: a.1 & 3 b.3 & 6 c.7 & 1 d.9 & 6 - ANSWER d. 9 & 6 Refer to Figure 333.20. For CR1 which, if any, of the operational diagrams below shows the relay energized (ON) to match the PB switch operation?

Select one: a. b. c. d. - ANSWER c. Refer to Figure 333.20. For CR2 which, if any, of the operational diagrams shows the relay energized (ON) to match the PB switch operation? Select one: a. b. c. d. - ANSWER a. For alternating relays, the contact open (or close) when power is ___ the coil. Select one: a.applied to b.removed from c.either a or b d.neither a nor b - ANSWER c. either a or b Single phasing is a term used to describe the ___. Select one: a.operation of a 3Ø motor on 2 of 3 phases b.maximum condition of voltage unbalance c.loss of one phase of a 3Ø system d.all of these - ANSWER d. all of these In addition to protecting a motor from single-phasing, phase failure relays provide protection against ___. Select one: a.voltage unbalance b.phase reversal c.undervoltage d.all of these - ANSWER d. all of these A 3Ø motor circuit has "lost" a leg. The motor is currently stopped. When this power is applied to a loaded 3Ø motor, the motor will ___. Select one: a.start and turn slowly for an indefinite period although it will draw excessive current b.draw LRC and will not turn - ANSWER b. draw LRC and will not turn

A voltage unbalance of 2% could cause a current unbalance of ___ or greater. Select one: a.10% b.8% c.10 A d.2% e.5% - ANSWER b. 8% The relay shown in Figure 402.221 will de-energize under which of these conditions? I. AØ is connected to terminal 7, BØ to terminal 6, & CØ to terminal 8 II. Power is lost on AØ or BØ or CØ III. Average line voltage drops below the preset level Select one: a.I or II only b.I only c.II or III only d.I or II or III e.II only - ANSWER d. I or II or III Refer to Figure 402.221. The relay is used in the pump control circuit shown at the right. The pump was running when a brown out occurred and caused the relay to open contact MPS. The pump ___ automatically restart when full voltage is restored. Select one: a.will b.will not - ANSWER a. will Refer to Figure 402.221. The relay is used in the pump control circuit shown at the right. While the motor was running, CØ was "lost" for 10 seconds and caused the relay to open contact MPS. The pump ___ automatically restart when CØ is restored. Select one: a.will b.will not - ANSWER a. will Refer to Figure 402.221. The relay is used in the pump control circuit shown at the right. Terminals T and X on the ladder diagram should be connected to terminals ___ on the relay.

Select one: a.1 & 2 b.1 & 3 c.2 & 3 - ANSWER a. 1 & 2 Refer to Figure 402.222. On the ladder diagram, point x should be connected to pin ___ on the MPS. Select one: a. b. c. d.2 - ANSWER d. 2 Refer to Figure 402.222. On the ladder diagram shown, point z should be connected to pin ___ on the MPS. Select one: a. b. c. d.2 - ANSWER c. 3 Because of the relative low voltages, working with batteries poses no electrical hazards. Select one: a.True b.False - ANSWER b. False Death by electrocution ___ possible while working with batteries. Select one: a.is b.is not - ANSWER a. is The gasses escaping from batteries are ___. Select one: a.explosive b.corrosive c.both a and b d.neither a nor b - ANSWER c. both a and b A UPS contains batteries. Select one:

a.True b.False - ANSWER a. True When working in battery rooms, you should always work ___. Select one: a.with someone else b.alone - ANSWER a. with someone else Rubber insulating blankets and other types of insulating materials can be very helpful in working safely around batteries and equipment. Select one: a.True b.False - ANSWER a. True Battery rooms require adequate ventilation to remove gasses. Select one: a.True b.False - ANSWER a. True Residential audio systems generally utilize ___-ohm speakers. Select one: a. b. c. d.50 - ANSWER a. 8 Audio systems can utilize ___ cables. Select one: a.CMR b.CMG c.CMP d.any of these - ANSWER b. CMG XX CCTV coax cable is constructed with a(n) ___ shield. Select one: a.copper b.aluminum c.either a or b - ANSWER a. copper

Because it provides less signal loss, quad-shield coaxial cable is used for ___ TV signals. Select one: a.analog b.digital - ANSWER b. digital Compared to crimp-on BNC coaxial cable connectors, screw-on BNC connectors permit a ___ signal loss. Select one: a.higher b.lower - ANSWER a. higher The maximum length limitation for RG-59 cable is ___ feet. Select one: a. b. c. d.330 - ANSWER a. 500 Cat 3, 5E, and 6 UTP cables used for ___ contain stranded conductors. Select one: a.patch cords b.local area networks - ANSWER a. patch cords When terminating UTP cables, the order of placement of the wires is ___. Select one: a.dependent upon the termination device b.not important - ANSWER a. dependent upon the termination device A copper cable transmits ___. Select one: a.photons b.electrons - ANSWER b. electrons Optical fiber cable is permitted to be installed ___. Select one: a.as direct burial cable b.underground in conduit c.as an aerial cable

d.indoors e.any of these - ANSWER e. any of these Fiber optic cables can be terminated with ___ connectors. Select one: a.ST b.LC c.FC d.any of these - ANSWER d. any of these For Voice/Data/Video network projects, the electrical contractor should ___. Select one: a.determine if he is to install and terminate the cabling b.determine if the network is to be powered by a 120-Vac circuit c.understand his responsibilities for the successful completion of the project d.determine if the work is to be performed under his construction permit e.all of these - ANSWER e. all of these Typical VDV networks include those provided for ___ systems. Select one: a.audio b.CATV c.telephone d.video e.all of these - ANSWER e. all of these Components of a basic network include ___. Select one: a.devices b.a head-end c.cable d.a public provider e.all of these - ANSWER e. all of these A computer network can be ___. Select one: a.hardwired b.wireless c.either a or b d.neither a nor b - ANSWER c. either a or b

When used for a business facility's computer network, the MDF may ___. Select one: a.be the primary connection point for the internet provider b.contain the client servers c.be connected to an IDF for large systems d.any of these - ANSWER d. any of these A CATV network may utilize a head-end to provide pre-recorded information. This information can be sent over a specific channel of the MATV system. ___ are typical applications for an MATV system. Select one: a.Universities b.Large hotels c.Dormitories d.all of these - ANSWER d. all of these From the head-end of a CCTV system, ___. Select one: a.cables are installed to uniquely identify each camera b.one cable is installed to the nearest camera and continues to the remaining cameras c.both a and b - ANSWER a. cables are installed to uniquely identify each camera A ___ system is used for surveillance and/or recorded documentation. Select one: a.MATV b.CATV c.CCTV d.any of these - ANSWER c. CCTV An audio system network can be utilized to provide ___. Select one: a.paging b.emergency notification c.background music d.any of these - ANSWER d. any of these Audio systems can utilize ___ cables. Select one: a.CMR b.CMG

c.CMP d.any of these - ANSWER d. any of these Cat ___ UTP cables are used for LANs. I. 6 II. 3 III. 5E Select one: a.I only b.I or II only c.I, II, or III d.II only e.I or III only - ANSWER e. I or III only The pairs in Cat ___ UTP cables have the least amount of twist. Select one: a.6 b.5E c.3 - ANSWER c. 3 Cat 3, 5E, and 6 UTP cables contain ___. Select one: a.22- to 24-gauge copper wire b.twisted pairs of wire c.unshielded wire d.all of these - ANSWER d. all of these Cat 3, 5E, and 6 UTP cables used for ___ generally contain solid conductors. Select one: a.patch cords b.local area networks - ANSWER b. local area networks The consistency of the twists and greater twist rate provide a ___ performance when using Cat 5E and 6 compared to Cat 3 cables. Select one: a.higher b.lower - ANSWER a. higher If the maximum permitted tension is exceeded when installing UTP cable, the performance can be affected due to ___.

Select one: a.attenuation b.crosstalk c.increased impedance d.all of these - ANSWER d. all of these The maximum channel length limitation for UTP cable is ___ feet. Select one: a.500 b.1000 c.750 d.330 - ANSWER d. 330 UTP cables can be terminated with ___. I. BNC connectors II. RJ-45 connectors III. 110 blocks Select one: a.I, II, or III b.II only c.I or II only d.III only e.II or III only - ANSWER e. II or III only ___ can be used as termination points for UTP cables. I. 110 blocks II. patch panels III. RJ-45 connectors Select one: a.I or II only b.II or III only c.I, II, or III d.III only e.II only - ANSWER c. I, II, or III The wire colors used in 4-pair UTP cables are ___. Select one: a.brown-orange-yellow-green b.orange-blue-green-red

c.red-blue-yellow-orange d.blue-orange-green-brown - ANSWER d. blue-orange-green-brown For a coaxial cable, the ___ serves as a conductor. Select one: a.shielding b.center conductor c.both a and b - ANSWER c. both a and b The construction of a coaxial cable serves to prevent ___. Select one: a.physical damage b.electromagnetic interference c.electrical hazards d.all of these - ANSWER b. electromagnetic interference CATV coax cable is constructed with a(n) ___ shield. Select one: a.copper b.aluminum c.either a or b - ANSWER b. aluminum A commonly used type of coaxial cable used for video applications is ___. Select one: a.RG11/U b.RG59/U c.RG6/U d.all of these - ANSWER d. all of these CATV coax cable is terminated with Type ___ connectors. Select one: a.BNC b.F c.either a or b - ANSWER b. F The maximum length limitation for RG-6 cable is ___ feet. Select one: a.500 b.1000 c.750

d.330 - ANSWER c. 750 The maximum length limitation for RG-11 cable is ___ feet. Select one: a.500 b.1000 c.750 d.330 - ANSWER b. 1000 When installing coaxial cable, the tension applied when pulling can not exceed ___ pounds. Select one: a.8 b.25 c.70 d.90 - ANSWER d. 90 After the termination of a coaxial cable is complete, there should be ___ between the shielding and the center conductor. Select one: a.continuity b.insulation - ANSWER b. insulation When installing coaxial cable, ___ end(s) shall be labeled. Select one: a.either b.both - ANSWER b. both Generally, ___ cable has a higher bandwidth and can transmit larger amounts of data. Select one: a.copper b.fiber optic - ANSWER b. fiber optic An optical fiber cable transmits ___. Select one: a.photons b.electrons - ANSWER a. photons ___ cable is more secure against eavesdropping because the cable must be physically tapped to do so.