IEC Year 3 |ACCURATE QUESTIONS |VERIFIED ANSWERS | LATEST UPDATE |NEW VERSION 2024- 2025, Exams of Physics

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IEC Year 3 |ACCURATE QUESTIONS

|VERIFIED ANSWERS | LATEST UPDATE

|NEW VERSION 2024-

2025|GUARANTEED PASS|

In a control circuit which of these drawings shows the maximum number of control relay coils that can be connected line-to-line in parallel? Select one: a. b. c. d.none of these show the maximum

• ANSWER d. none of these show the maximum In a control circuit which of these drawings shows the components connected to operate correctly? Select one: a. b. c. d.any of these
• ANSWER b. NEMA or industry standard Symbol I, shown in Figure 320.11, represents a ___ when used in a ladder diagram. Select one: a.siren b.buzzer c.bell
  • ANSWER c. bell The NEMA or industry standard symbol for a buzzer is shown at ___ in Figure 320.11. Select one: a.III b.II c.I
  • ANSWER a. III

The NEMA or industry standard symbol for a double-break, momentary-contact, single- circuit, normally open pushbutton switch is shown at ___ in Figure 320.12. Select one: a.V b.II c.I d.IV e.III

• ANSWER d. IV The NEMA or industry standard symbol for a SPDT, single-break switch is shown at ___ in Figure 320.12. Select one: a.V b.II c.I d.IV e.III
• ANSWER c. I The NEMA or industry standard symbol for a momentary-contact, single-circuit, normally closed, double-break pushbutton switch is shown at ___ in Figure 320.12. Select one: a.V b.II c.I d.IV e.II I - ANSWER e. III The NEMA or industry standard symbol for a light is shown at ___ in Figure 320.13. Select one: a.II b.III c.I
• ANSWER c. I Symbol ___ in Figure 320.14 represents the NEMA or industry standard symbol for a fuse. Select one: a.II

b.I c.III

• ANSWER a. II Select (as required) the NEMA or industry standard symbol for the component shown below: Select one: a. b. c. d.
• ANSWER d. Select (as required) the NEMA or industry standard symbol for the component shown below: Select one: a. b. c. d.
  • ANSWER b. Select (as required) the NEMA or industry standard symbol for the component shown below: Select one: a. b. c. d.
  • ANSWER b. Select (as required) the NEMA or industry standard symbol for the component shown below: Yellow Select one: a. b. c. d.
  • ANSWER d.

Select (as required) the NEMA or industry standard symbol for the component shown below: Select one: a. b. c. d

. - ANSWER a. Select (as required) the NEMA or industry standard symbol for the component shown below. This momentary switch is spring held in the position shown and is used to release a door magnet. Select one: a. b. c. d. - ANSWER c. Select (as required) the NEMA or industry standard symbol for the component shown below: Select one: a. b. c. d. - ANSWER a. Standardized ___ symbols are utilized in wiring diagrams. Select one: a.ANSI b.NEC c.NEMA d.UL

• ANSWER c. NEMA On a ladder diagram, the branch circuit conductors are represented by Line 1 (L1) and Line 2 (L2). Select one: a.True b.False

• ANSWER a. true For a 2-wire control circuit, the grounded conductor (neutral) is permitted to be connected to ___. Select one: a.L b.L c.either L1 or L
• ANSWER b. L A line on a ladder diagram represents a wire. Select one: a.True b.False
• ANSWER a. true A dot on a ladder diagram indicates a terminal or wire connection. Select one: a.True b.False
• ANSWER a. true Refer to Diagram I in Figure 320.15. The load is energized when ___ closed. Select one: a.all the switches are b.any one of the switches is
• ANSWER b. any one of the switches is In a control circuit, all wires connected to L2 will have the same wire reference number. Select one: a.True b.False
• ANSWER a. true When wiring a control circuit, good wiring practice is to ___. I. install wire markers II. mark completed connections on diagram Select one: a.I only

b.II only c.both I & II d.neither I nor II

• ANSWER c. both I & II ___ diagrams are generally used to illustrate control circuits. Select one: a.Application b.Operational c.Wiring d.Ladder
• ANSWER d. ladder Where connected across-the-line (line-to-line) in a control circuit, ___ is the maximum number of pilot device contact sets that can be series-connected. Select one: a. b. c. d.as many as required
• ANSWER d. as many as required In a numerical cross-reference system, ___ contacts are underlined. Select one: a.auxiliary b.normally open c.overload d.normally closed
• ANSWER d. normally closed Refer to Figure 324.51. Component is connected in ___with component. Select one: a.parallel b.series
• ANSWER b. series Refer to Figure 324.51. Component is connected in ___with component. Select one: a.parallel b.series - ANSWER b. series

Refer to Figure 324.51. Component is connected in ___ with component. Select one: a.parallel b.series - ANSWER b. series When transferring materials from lifting equipment to an elevated level, guardrails ___ permitted to be removed. Select one: a.are b.are not - ANSWER a. are Guardrails are required if an unglazed window opening ___. Select one: a.presents a fall hazard of more than 6 feet to the level below b.is not at least 39 inches higher than the floor height of the elevated platform c.has a sill that is less than 39 inches above the working height d.any of these - ANSWER d. any of these Guardrails are required at many locations. These locations include ___. Select one: a.scaffolds b.elevator shafts c.balconies d.any of these e.openings in walls and floors - ANSWER d. any of these The purpose of a toeboard surrounding an elevated platform is to ___. Select one: a.prevent tools from being knocked onto workers below b.provide a suitable securement for fall protection equipment c.both a and b d.neither a nor b - ANSWER a. prevent tools from being knocked onto workers below Guardrails are installed to ___. Select one: a.possibly save you from a serious injury or worse b.prevent you from falling to a lower level c.both a and b d.neither a nor b - ANSWER c. both a and b

The requirements for most guardrails dictate that a guardrail be installed between ___ inches above the elevated floor or walking surface. Select one: a.48 and 60 b.39 and 42 c.32 and 39 d.12 and 60 - ANSWER b. 39 and 42 A(n) ___ consists of a legend plate, an operator, and one or more contact blocks. Select one: a. motor starter b. industrial relay c. control transformer d. industrial pushbutton - ANSWER D. Industrial push button Which of the pushbutton operators below would be best suited for an emergency shutdown of a computer room where the switch is located next to the principal exit door? Select one: a. flush button b. extended button c. 2-position selector switch d. extended button under a hinged cover - ANSWER d. extended button under a hinged cover A 3-position foot switch is normally spring loaded to return to the ___ position when the force is removed. Select one: a. ON b. OFF - ANSWER b. OFF Refer to Figure 323.13. The leads of a voltmeter were placed on Terminals 2 & 3. If the meter indicates 0 volts, what is the status of the switch. Select one: a. Open b. Closed - ANSWER a. Open Select (as required) the NEMA symbol for a 2-position selector switch with single-break contacts. Select one:

a. b. c. d. - ANSWER a. Select (as required) the NEMA symbol for a normally open foot switch. Select one: a. b. c. d. - ANSWER b. A manual control circuit is any circuit that requires ___ to operate. Select one: a. 3-wire control b. a linear mechanical force c. action by a person d. none of these - ANSWER c. Action by a person Refer to Figure 321.14. An ohmmeter reading between Points J & M would indicate ___ Ω. Select one: a. 0 to 0. b. 10 to 400 c. OL (or ∞) - ANSWER a. 0 to 0. The switching contacts of any control device are rated electrically by the manufacturer for the maximum ___ the contacts can withstand. Select one: a. ambient temperature and voltage b. voltage and current c. ambient temperature and current d. humidity and barometric pressure - ANSWER b. Voltage and current If contacts for control devices (manual or automatic) are added, they will be placed anywhere between points ___ on the 120-volt circuit, as shown here. Select one: a. I & IV b. II & III only c. I & II only d. I & III only - ANSWER c. I & II only

Resistance or continuity measurements are made with the circuit ___. Select one: a. energized b. de-energized - ANSWER b. de-energized Selector switches are available with ___ positions. Select one: a. two b. more than 3 c. three d. a, b, or c - ANSWER d. a, b, or c The correct symbol to use for the switch, shown at I in Figure 323.3, is ___. Select one: a. b. c. d. - ANSWER d. Which of these truth tables is correct for the switch shown at the right? Select one: a. b. c. d. - ANSWER d. Refer to Figure 323.9. Before the PB switch is pressed, you place your ohmmeter leads between points 3 & 4 on the T-strip and get a reading of 0.2 ohms. The switch contacts connected points 3 & 4 are ___ contacts. Select one: a. NO b. NC - ANSWER b.NC Refer to Figure 323.13. If the leads of a voltmeter were placed on Terminals 1 & 2, the meter should indicate ___ volts. The switch is closed and each battery has a rating of 12 volts. Select one: a. 0 b. 6

c. 12 d. 24 - ANSWER a. 0 Select (as required) the NEMA symbol for a momentary-contact, mushroom-head pushbutton switch (with 1-NC/1-NO contacts). Select one: a. b. c. d. - ANSWER C. Select (as required) the NEMA symbol for a wobble stick Select one: a. b. c. d. - ANSWER a. Select (as required) the NEMA symbol for a normally closed foot switch. Select one: a. b. c. d. - ANSWER c. Practicing proper bending, lifting, and carrying techniques can assist in avoiding painful back injuries. Select one: a. True b. False - ANSWER a. true Back injuries can be ___. Select one: a. permanent b. severe c. unnecessary d. painful e. all of these - ANSWER e. all of these Muscle strains and sprains are more likely to occur at the ___ of the work day. Select one:

a. beginning b. end - ANSWER a. beginning Although back injuries include muscle strains and sprains, other structural back injury could occur to ___. Select one: a. the spinal cord b. nerves c. the spine d. all of these - ANSWER d. all of these When lifting, you should ___. Select one: a. bend your legs and lift straight up b. keep the load as far away from your body as possible c. both a and b d. neither a nor b - ANSWER a. bend your legs and lift straight up Do not lift and twist your back at the same time. Select one: a. True b. False - ANSWER a. true Weak muscles are ___ likely to be strained and sprained. Select one: a. less b. more - ANSWER b. more Charging a tank is also known as ___ control and maintains the level by adding liquid. Select one: a.pump b.sump - ANSWER a. pump Where the symbol is used in a diagram, the contacts would ___ if the monitored material (movement, liquid, air, pressure, etc) increased above this setting. Select one: a.open b.close - ANSWER b. close The correct symbol to use for a NO-HC limit switch is ___.

Select one: a. b. c. d. - ANSWER c. The symbol ___ would be used to represent the NC contacts in the device shown at IV in Figure 323.4. Select one: a. b. c. d. e. - ANSWER a. Equipment IV, shown in Figure 323.8, has ___ set(s) of NC contacts. Select one: a. b. c. d. e.1 - ANSWER e. 1 Which of the following is a manual control device? Select one: a.liquid level (float) switch b.limit switch c.pressure switch d.momentary contact NC pushbutton switch - ANSWER d. momentary contact NC pushbutton switch A flow switch is a control switch that detects the movement of fluids, such as ___. Select one: a.oil b.water c.chlorine d.any of these - ANSWER d. any of these Select (as required) the NEMA symbol for a normally open flow switch. Select one:

a. b. c. d. - ANSWER c. Although it can be used to detect the level of some liquids, a(n) ___ level switch detects the dielectric variation when products such as shredded paper are and are not in contact with the probe. Select one: a.mechanical b.variometric c.capacitive d.magnetic e.ultrasonic - ANSWER c. capacitive The symbol would be used for an ___. Select one: a.NO close-on-rise switch b.NC open-on-rise switch - ANSWER a. NO close-on-rise switch The correct symbol to use for a NC limit switch is ___. Select one: a. b. c. d. - ANSWER d. The correct symbol to use for a NC-HO limit switch is ___. Select one: a. b. c. d. - ANSWER b. The symbol ___ would be used to represent the NO contacts in the device shown at II in Figure 323.4. Select one: a. b. c. d.

e. - ANSWER e. The correct symbol to use for a NC flow switch is ___. Select one: a. b. c. d. e. - ANSWER a. A ___ switch has a set of contacts that are operated by the movement of a piston, bellows, or diaphragm against a set of springs. Select one: a.limit b.flow c.pressure d.none of these - ANSWER c. pressure Select (as required) the NEMA symbol for a normally open, held-closed limit switch. Select one: a. b. c. d. - ANSWER d. The equipment shown in Figure 323.11 is a ___ switch. Select one: a.vacuum b.liquid level c.pressure d.temperature e.limit - ANSWER e. limit Refer to Figure 323.11. When the contacts between 3 & 4 are closed, the contacts between 1 & 2 are ___. Select one: a.also closed b.open - ANSWER b. open Refer to Figure 323.11. This switch has ___ set(s) of NC contacts.

Select one: a. b. c. d. e.1 - ANSWER e. 1 Refer to Figure 324.44. The 120-volt circuit should be connected to terminals ___ on the time clock. Select one: a.1 & 3 b.3 & 4 c.2 & 4 d.1 & 2 - ANSWER d. 1 & 2 Refer to Figure 324.44. This is a(n) ___ time clock. Select one: a.SPDT b.DPDT c.3PST d.SPST e.DPST - ANSWER a. SPDT Select (as required) the NEMA symbol for a normally open vacuum switch. Select one: a. b. c. d. - ANSWER c. Select (as required) the NEMA symbol for a normally open temperature switch. Select one: a. b. c. d. - ANSWER d. Which of the following is an automatic control device? I. single-pole toggle switch II. NC momentary contact pushbutton switch III. float switch

IV. NO momentary contact pushbutton switch Select one: a.I, II & IV only b.I only c.III only d.I, II, III & IV e.II & IV only - ANSWER c. III only Individuals who require reading glasses can obtain safety eye protection with magnification lenses. Select one: a.True b.False - ANSWER a. true Safety eyewear with shaded lenses ___ be worn indoors. Select one: a.should b.should not - ANSWER b. should not It is important to make certain that safety eyewear meets the ___ standard Z87.1 - 2003 for industrial safety eyewear. Select one: a.CSA b.OSHA c.UL d.ANSI - ANSWER d. ANSI Safety eyewear is available at ___. Select one: a.most hardware stores b.electrical supply houses c.safety speciality stores d.all of these - ANSWER d. all of these The Prevent Blindness America website states that more than ___ Americans injure their eyes at work each year. Select one: a.7, b.700, c.50,

d.100,000 - ANSWER b. 700, ___% of workplace eye injuries can be prevented by using proper safety eyewear. Select one: a. b. c. d.90 - ANSWER d. 90 The coil rating on the equipment shown in Figure 321.21 ___. Select one: a.cannot be determined b.is 240 volts c.is 120 volts - ANSWER c. is 120 volts Refer to Figure 321.11. Equipment I is a ___. Select one: a.power pole b.coil c.control transformer d.relay e.starter - ANSWER d. relay Power to the loads in a 230-volt circuit can be controlled by a relay that opens and closes contacts in a 24-volt circuit. Select one: a.True b.False - ANSWER a. true For general-purpose relays, the contact current rating for switching DC is ___ the contact rating for switching AC. Select one: a.more than b.lower than c.equal to - ANSWER b. lower than A contactor, that closes when power is applied to the coil and releases when power is removed, is referred to as ___ held. Select one: a.mechanically

b.electrically - ANSWER b. electrically The coils contained within solenoids, relays, starters, and contactors ___ when they fail. Select one: a.can be repaired b.must be replaced - ANSWER b. must be replaced Where the maximum line current of a 3Ø load is 60 amps, a 3-pole NEMA contactor should have a rating that is at least ___ amps. Select one: a. b. c.103. d.34. e.60 - ANSWER e. 60 A 230-volt coil has an impedance that is ___ a 115-volt coil. Both have 600 VA inrush ratings. Select one: a.higher than b.lower than c.the same as - ANSWER a. higher than It ___ permitted to use a double-pole manual contactor to control a thermally-protected, 1 - phase 240-volt motor. Select one: a.is b.is not - ANSWER a. is Select (as required) the NEMA symbol for a normally closed set of contacts (contained in a relay or a contact block). Select one: a. b. c. d. - ANSWER b. Where a relay contains one set of NO and one set of NC contacts, these are interlocked so that they are always in opposite states. Select one:

a.True b.False - ANSWER a. true Refer to Figure 321.21. An ohmmeter reading between Points L & R would indicate ___ Ω. Select one: a.10 to 400 b.0 to 0. c.OL (or ∞) - ANSWER a. 10 to 400 Refer to Figure 321.21. An ohmmeter reading between Points H & N would indicate ___ Ω. Select one: a.0 to 0. b.10 to 400 c.OL (or ∞) - ANSWER a. 0 to 0. Refer to Figure 321.22. The contacts of this equipment have a rating of ___ amps at 120 volts. Select one: a.1 to 2 b. c.1/ d.12 - ANSWER d. 12 Refer to the relay wiring diagram shown in Figure 321.24. This is a(n) ___ relay. Select one: a.SPDT b.3PST c.DPDT d.3PDT e.DPST - ANSWER d. 3PDT Refer to the relay wiring diagram shown in Figure 321.24. The coil is connected between terminals ___. Select one: a.5 & 7 b.1 & 4 c.1 & 11 d.2 & 10 - ANSWER d. 2 & 10

General-purpose (ice-cube-type) relays ___ have replaceable contacts. Select one: a.do b.do not - ANSWER b. do not In a control circuit which of these drawings shows the components connected to operate correctly? Select one: a. b. c. d.any of these - ANSWER b. In a numerical cross-reference system, ___ contacts are underlined. Select one: a.auxiliary b.normally open c.overload d.normally closed - ANSWER d. normally closed Refer to Figure 324.52. Point J on the ladder diagram should be connected at terminal ___ on the equipment. Select one: a.1 b.either 2 or 3 c.4 d.either 1 or 4 e.2 - ANSWER c. 4 Refer to Figure 324.53. Point G on the ladder diagram should be connected at terminal ___ on the equipment. Select one: a.6 b.10 c.3 d.7 e.2 - ANSWER d. 7 EMR is an abbreviation for ___. Select one:

a.Electro-Mechanical Relay b.Energy-Mitigation Rectifier c.Electrical-Motion Ramp d.Electron-Migration Response - ANSWER a. electro-mechanical relay The circuit breaker should be connected to points ___ in Figure 323.5. Select one: a.X, Y & Z b.Z, V & W c.U, G & H d.D, K, J & I - ANSWER b. Z, V & W The contactor shown in Figure 323.5 should have a coil that is rated for ___ volts. Select one: a.120 b.480 c.277 - ANSWER a. 120 Refer to Figure 324.41. Time clock terminal 4 should be connected to terminal ___ on the relay. Select one: a.both 1 & 2 b.either 1 or 8 c.both 3 & 6 d.2 only e.8 only - ANSWER d. 2 only Refer to Figure 324.41. Which of the diagrams, shown below, would correctly operate the load as required? Select one: a. b. c. d. - ANSWER d. Refer to Figure 324.42. The two 240-volt wires connected to terminals ___ on the relay. Select one: a.2 & 7 b.1 & 3 c.4 & 5 d.3 & 6

e.1 & 8 - ANSWER e. 1 & 8 Refer to Figure 324.42. The control circuit neutral could be connected to terminal(s) ___ on the relay. Select one: a.both 1 & 2 b.2 only c.both 2 & 3 d.3 only e.4 only - ANSWER b. 2 only Refer to Figure 324.43. Which of the diagrams, shown below, would correctly operate the load as required? Select one: a.I only b.II only c.either I or II d.neither I nor II - ANSWER a. I only Refer to Figure 324.45. The current time is 8 am. When the HOA switch is in the AUTO position, ___ is energized. I. the TC motor II. the white light III. the green light IV. the transformer V. relay R1 Select one: a.I & IV only b.I,II, III & IV only c.I, II & IV only d.I, IV & V only - ANSWER a. I & IV only Refer to Figure 324.45. The current time is 9 pm. When the HOA switch is in the AUTO position, ___ is energized. I. the TC motor II. the white light III. the green light IV. the transformer V. relay R1 Select one:

a.I & IV only b.I,II, III & IV only c.I, II & IV only d.I, IV & V only e.all of these - ANSWER e. all of these Refer to Figure 324.46. The current time is 7 am. When the HOA switch is in the AUTO position, ___ is energized. I. relay R2 II. the white light III. the green light Select one: a.I & II only b.I & III only c.I, II & III d.I only e.II & III only f.none of these - ANSWER f. none of these Refer to Figure 324.47. The current time is 11 pm. When the HOA switch is in the AUTO position, the ___ light is energized. Select one: a.white b.green c.both a and b d.neither a nor b - ANSWER c. both a and b Refer to Figure 324.47. The current time is 1 pm. When the HOA switch is in the AUTO position, the ___ light is energized. Select one: a.white b.green c.both a and b d.neither a nor b - ANSWER d. neither a nor b SSR is an abbreviation for ___. Select one: a.Static-Switching Relay b.Silicon-Sealed Rectifier c.Solid-State Relay d.Speed-Sensing Response - ANSWER c. solid-state relay

EMR is an abbreviation for ___. Select one: a.Electro-Mechanical Relay b.Energy-Mitigation Rectifier c.Electrical-Motion Ramp d.Electron-Migration Response - ANSWER a. electro-mechanical relay The four basic switching types for SSRs include ___. Select one: a.zero switching b.instant-on c.peak switching d.analog switching e.all of these - ANSWER e. all of these Generally, SSRs have ___ output contact(s). Select one: a.2 (1NO/1NC) b.4 (2NO/2NC) c.only one - ANSWER c. only one The failure rate of SSRs ___ as the ambient temperature increases. Select one: a.increases b.decreases - ANSWER a. increases To help dissipate the heat generated within an SSR, the relays are mounted ___. Select one: a.on heat sinks b.in free air - ANSWER a. on heat sinks To help prevent overvoltage problems, a varistor is connected between the ___ terminals of an SSR. Select one: a.input b.output - ANSWER b. output The coil of an EMR performs the same function as ___ of an SSR.