2023 Commercial Electrical Inspector – Practice Quiz (Untimed)

2023 Commercial Electrical Inspector (Untimed)

80 Questions

3.5 Hours

1 / 80

1. What is the minimum bending radius required for shielded or lead-covered conductors during or after installation?

A) 10 times the overall diameter

B) 7 times the overall diameter

C) 12 times the overall diameter

D) 8 times the overall diameter

2 / 80

2. Metal raceways attached to elevator cars must be bonded to metal parts of the car that are bonded to which conductor?

A) The motor frame

B) The equipment grounding conductor

C) The neutral conductor

D) The grounded conductor

3 / 80

3. In a major repair garage (lighter-than-air fuels), the area within 18 in. of the ceiling is unclassified if ventilation of at least 0.3text{ m}^{3}/text{min}/text{m}^{2} / 1text{ ft}^{3}/text{min}/text{ft}^{2}) is provided with suction taken from where?

A) The center of the room

B) The main ventilation duct intake

C) A point within 12 in. of floor level

D) A point within 18 in. of the highest point in the ceiling

4 / 80

4. Dimmer and electronic control switches shall be used only to control which type of loads, unless listed for the control of other loads?

A) Permanently connected loads, such as incandescent luminaires

B) Temporary lighting loads

C) Non-dimmable fixtures

D) Fixed appliance loads

5 / 80

5. Recessed high-intensity discharge luminaires designed to be installed in wall or ceiling cavities must have thermal protection and be identified as what?

A) Listed for damp locations

B) Thermally protected

C) Type IC

D) Inherently protected

6 / 80

6. What must normally non-current-carrying conductive materials enclosing electrical conductors or equipment be connected to, according to 250.4(A)(2)?

A) The nearest phase conductor

B) Earth, so as to limit the voltage to ground on these materials

C) Only the main bonding jumper

D) The largest grounding electrode conductor

7 / 80

7. If the supply conductors from a permanently installed outdoor generator set terminate at a disconnecting means in or on a building, what requirements must that disconnecting means meet?

A) The requirements of 445.19(C)

B) The requirements of 225.36

C) The requirements of 702.5(C)

D) The requirements of 230.85

8 / 80

8. What voltage shall be considered when determining the required interrupting rating of equipment intended to interrupt current at fault levels?

A) The nominal circuit voltage

B) The highest system voltage

C) The calculated fault voltage

D) The lowest nominal voltage

9 / 80

9. ENT shall not be used in theaters and similar locations, except as provided in which two specific sections?

A) 518.4 and 520.5

B) 410.117(C) and 518.4

C) 501.10(A) and 504.10(B)

D) 362.10(8) and 300.5

10 / 80

10. For an irrigation machine with inherent intermittent duty, what percentage of the largest motor’s full-load current rating is used when determining the equivalent continuous-current rating?

A) 125 percent

B) 150 percent

C) 80 percent

D) 100 percent

11 / 80

11. What is required to be provided to prevent contact with nonshielded cables or energized parts of oil-filled cutouts?

A) Remote operation

B) Fire extinguishers

C) Suitable barriers or enclosures

D) Warning signs

12 / 80

12. What restriction applies to bare or covered aluminum or copper-clad aluminum grounding electrode conductors without an extruded polymeric covering?

A) Must be installed outside

B) Must be installed in a raceway

C) Must be protected against physical damage

D) Shall not be installed where subject to corrosive conditions or be installed in direct contact with concrete

13 / 80

13. For metal-enclosed busways over 1000 volts, what is the goal regarding temperature rise from induced circulating currents in adjacent ferrous metal parts?

A) It will not exceed the busway operating temperature

B) It will not exceed 90°C (194°F)

C) It will be evenly distributed

D) It will not be hazardous to personnel or constitute a fire hazard

14 / 80

14. For unenclosed spray processes, electrical wiring and equipment located outside but within 20 ft. horizontally and 10 ft. vertically of the enclosed spray area shall be suitable for which classification?

A) Class I, Zone 0

B) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 locations

C) Unclassified

D) Class I, Division 1 or Zone 1

15 / 80

15. Short-circuit current rating markings are not required for industrial control panels containing only which components?

A) Grounding components

B) Control circuit components

C) Non-motor loads

D) Feeder terminals

16 / 80

16. Masts used to support final spans of feeders or branch circuits must be installed in accordance with 225.17(A) and (B). True or False?

A) False

B) False, only 225.17(A) applies

C) True

D) True, only if the mast is over 6 ft

17 / 80

17. Which wiring method is permitted to be installed in exposed or concealed locations under metal-corrugated sheet roof decking without maintaining the 38 mm (1 1/2 in.) spacing requirement?

A) Electrical nonmetallic tubing (ENT)

B) Rigid PVC conduit

C) Rigid metal conduit and intermediate metal conduit (IMC)

D) Electrical metallic tubing (EMT)

18 / 80

18. Where a pipe heating cable outlet is installed in a park trailer, it must be located within what maximum distance of the cold water inlet?

A) 300 mm (1 ft)

B) 600 mm (2 ft)

C) 900 mm (3 ft)

D) 450 mm (1.5 ft)

19 / 80

19. For LP-Gas dispensing devices, what is the extent of the Class I, Division 1 classified location?

A) 10 ft. in all directions

B) Entire space within the dispenser enclosure; 18(in.) from the exterior surface of the dispenser enclosure to an elevation of 4 ft. above the base; and unventilated pits/trenches below

C) 5 ft. in all directions

D) Up to 18(in.) above ground and within 20 ft. horizontally

20 / 80

20. Factory-installed receptacle outlets that are part of a permanently installed electric baseboard heater shall not be connected to which circuits?

A) The service entrance circuits

B) GFCI protected circuits

C) General-purpose lighting circuits

D) The baseboard heater circuits

21 / 80

21. A cable, raceway, or box installed under metal-corrugated sheet roof decking must be supported so there is not less than what minimum clearance measured from the lowest surface of the roof decking to the top of the installation?

A) 38 mm (1 1/2 in.)

B) 25 mm (1 in.)

C) 50 mm (2 in.)

D) 64 mm (2 1/2 in.)

22 / 80

22. In supervised industrial installations (Part VIII), where the overcurrent device is rated over 800 amperes, the ampacity of the conductors it protects shall be equal to or greater than what percentage of the rating of the overcurrent device?

A) 90 percent

B) 95 percent

C) 92.5 percent

D) 80 percent

23 / 80

23. Which types of RMC are permitted under all atmospheric conditions and occupancies?

A) Only galvanized steel RMC

B) All listed types of RMC

C) Galvanized steel, stainless steel, and red brass RMC

D) Aluminum and galvanized steel RMC

24 / 80

24. To determine the equivalent horsepower of a disconnecting means for a hermetic refrigerant motor-compressor, the horsepower rating corresponding to which current rating must be selected from the applicable tables?

A) 125 percent of the rated-load current

B) The rated-load current or branch-circuit selection current, whichever is greater, and also the locked-rotor current

C) Only the locked-rotor current

D) Only the rated-load current

25 / 80

25. Installations under the exclusive control of an electric utility located on property owned or leased by the utility for the purpose of transformation are not covered by this Code. True or False?

A) False

B) False, unless the property is a substation

C) True, only if the property is over 10 acres

D) True

26 / 80

26. A power transformer connected toward the interactive inverter output in a Solar PV system is permitted without overcurrent protection from the inverter if its current rating on the side connected toward the inverter output is not less than what value?

A) The maximum available fault current

B) The inverter peak output current

C) The inverter nominal output current

D) The rated continuous output current of the inverter

27 / 80

27. What type of ignition sources involving equipment features are specifically not covered by Article 505?

A) Arcing contacts

B) Nonelectrical potential sources of ignition

C) Hot surfaces created by electrical faults

D) Sparking from terminal connections

28 / 80

28. If a single-phase, 2-wire ESS output is connected to the grounded/neutral conductor of a 3-wire system, the ampacity of the grounded/neutral conductor shall not be exceeded by the sum of the maximum unbalanced neutral load current plus what other rating?

A) The ESS(s) output rating

B) The full load current of the largest utilization equipment

C) 125 percent of the ESS output rating

D) The maximum available fault current

29 / 80

29. What is the ampacity for 4/0 AWG aluminum conductor, Type XHHW-2, installed in a raceway or earth (direct buried) under standard conditions (30°C ambient, 3 CCC)?

A) 205 amperes

B) 230 amperes

C) 180 amperes

D) 260 amperes

30 / 80

30. For pull and junction boxes used on systems over 1000 volts, which section covering conductor fill is specifically required to be complied with?

A) 314.28(A)

B) 314.2, 314.3, 314.4, and 314.5

C) 314.16(B)

D) 314.71

31 / 80

31. What is the ampacity for a 12 AWG, 90°C conductor, when there are up to four simultaneously energized ac conductors in a cable, rated for 60-minute service?

A) 33 amperes

B) 40 amperes

C) 36 amperes

D) 30 amperes

32 / 80

32. If tap conductors not over 3 m (10 ft) long leave the enclosure or vault in which the tap is made, the ampacity of the tap conductors shall be not less than what proportion of the rating of the feeder overcurrent protective device?

A) One-third

B) One-fourth

C) One-sixth

D) One-tenth

33 / 80

33. When unused metallic plugs or plates are used to close unused openings in nonmetallic enclosures, what minimum distance must they be recessed from the outer surface of the enclosure?

A) 10 mm (3/8 in.)

B) 6 mm (1/4 in.)

C) 3 mm (1/8 in.)

D) They must be flush with the outer surface.

34 / 80

34. Conductors that are more finely stranded than Class B and Class C stranding shall use connectors and terminals that are identified for what?

A) 90°C operation

B) Direct burial use

C) The specific conductor class or classes

D) Low-voltage systems

35 / 80

35. Ground clamps or other fittings exposed to physical damage must be enclosed in what materials?

A) Metal, wood, or equivalent protective covering

B) Schedule 40 PVC or equivalent

C) Flexible metal conduit

D) Galvanized steel only

36 / 80

36. Open service conductors must be attached to fittings identified for use with service conductors or to noncombustible, nonabsorbent insulators that are securely attached to what?

A) The neutral bus

B) A service mast coupling

C) The utility pole

D) The building or other structure

37 / 80

37. A surge arrester shall not be installed where its rating is less than the maximum continuous phase-to-ground voltage available at what point?

A) The disconnecting means

B) The point of application

C) The transformer secondary

D) The service point

38 / 80

38. In addition to the requirements of Article 470, the installation of oil-filled reactors shall comply with applicable requirements of which two specific Parts of Article 450?

A) Part III and Part IV

B) Part I and Part II

C) Part II and Part III

D) Part I and Part IV

39 / 80

39. Where are splices or taps permitted within auxiliary gutters?

A) Only at the ends of the gutter

B) Only in separate splice compartments

C) Where they are accessible by means of removable covers or doors

D) Only for conductors 10 AWG or smaller

40 / 80

40. When can the authority having jurisdiction (AHJ) grant permission for feeder ampacity less than 100% of the total connected space heating load?

A) If reduced loading results from units operating on duty-cycle or intermittently

B) If the conductor temperature rating exceeds 90°C

C) If the load current is less than 50 amperes

D) If the feeder conductors are protected by ground-fault equipment protection

41 / 80

41. In recreational vehicle parks, GFCI protection shall only be required for what specific rating of receptacles installed in the recreational vehicle site equipment?

A) 125-volt, single-phase, 15- and 20-ampere receptacles

B) All 125-volt receptacles

C) 30-ampere and 50-ampere receptacles

D) 208Y/120-volt receptacles

42 / 80

42. Isolating switches required for services over 1000 volts must be provided with a means for readily connecting the load side conductors to a grounding electrode system or equipment ground busbar when the switch is disconnected from what?

A) The utility meter

B) The service disconnect

C) The source of supply

D) The equipment grounding conductor

43 / 80

43. Cable trays are permitted to extend through walls/partitions or floors provided the installation, complete with installed cables, is made in accordance with which section?

A) 392.3

B) 300.21

C) 392.56

D) 314.28

44 / 80

44. Which of the following is required to be included in a Cablebus system?

A) Condensation drains at low points

B) Overcurrent devices for conductor protection

C) Fittings for terminations in or on connected apparatus or equipment

D) Expansion fittings for long straight runs

45 / 80

45. If a disconnecting means is required to be lockable open, the provisions for locking shall:

A) Only be required for equipment rated over 200 A

B) Remain in place with or without the lock installed

C) Only apply to service disconnecting means

D) Be removable to prevent unauthorized locking

46 / 80

46. Ungrounded conductors tapped from a grounded system must be controlled by switching devices that manually switch all poles together if the device serves as a disconnecting means for which appliance?

A) A permanent air-conditioning unit

B) An electric oven (wall-mounted)

C) A refrigerator

D) A fixed electric space-heating unit

47 / 80

47. Service conductors supplying one building are generally prohibited from passing through which area of another building or structure?

A) The roof overhang

B) The interior

C) An underground raceway

D) The exterior wall

48 / 80

48. What are the two standard ampere ratings listed in Table 240.6(A) immediately following 600 amperes?

A) 650, 750

B) 700, 800

C) 700, 800

D) 800, 1000

49 / 80

49. Which factor must be applied to the maximum load to be served when determining the minimum service-entrance conductor size, in addition to continuous load adjustments?

A) The feeder neutral reduction factor

B) The 125% continuous load factor only

C) Any adjustment or correction factors (e.g., ambient temperature or bundling)

D) The demand factor in 220.45

50 / 80

50. What is the maximum number of electronic control switches permitted on a single branch circuit, as specified in the exception to 404.2(C)}?

A) Fifteen

B) Five

C) Three

D) Ten

51 / 80

51. Each smoothing iron and other cord-and-plug-connected electrically heated appliance intended to be applied to combustible material shall be equipped with what component?

A) A protective barrier

B) A 90 (C) rated cord

C) A thermal cutout

D) An approved stand

52 / 80

52. What is the minimum trade size permitted for NUCC?

A) Metric designator 21 (trade size 3/4)

B) Metric designator 12 (trade size 3/8)

C) Metric designator 16 (trade size 1/2)

D) Metric designator 35 (trade size 1 1/4)

53 / 80

53. If multiple Class A protective devices are used for an appliance, how many are required by the code?

A) Exactly two devices

B) Exactly one device

C) Shall not be required

D) Three devices minimum

54 / 80

54. What must be coordinated to prevent damaging or dangerous temperatures in conductors or conductor insulation under short-circuit conditions?

A) Grounding method, bonding requirements, and equipment listing

B) The operating time of the protective device, the available short-circuit current, and the conductor used

C) Phase rotation, system voltage, and conductor material

D) Cable length, ambient temperature, and load

55 / 80

55. On 3-phase, 3-wire circuits, an overcurrent relay element in the residual circuit of the current transformers shall be permitted to replace which component?

A) The ground-fault relay element

B) The instantaneous trip element

C) The neutral relay element

D) One of the phase relay elements

56 / 80

56. What minimum marking requirement must be field-applied at the permanent connection point for a temporary generator serving an Emergency System?

A) System voltage, maximum amperage, short-circuit current rating of the load side of equipment supplied, and ungrounded conductor identification

B) The date of installation and testing schedule

C) The generator prime mover type and fuel source

D) The phase rotation and grounding electrode type

57 / 80

57. In outdoor installations of service equipment, switchboards, or motor control centers, the dedicated equipment space must extend from grade to a height of how far above the top of the equipment?

A) The structural ceiling

B) 2.0 m (6 1/2 ft)

C) 1.8 m (6 ft)

D) 1.5 m (5 ft)

58 / 80

58. Services used for temporary installations shall be installed in conformance with which parts of Article 230, as applicable?

A) Parts III through V

B) Parts II through VII

C) Parts I through VIII

D) Parts I through IV

59 / 80

59. Where shall the grounded conductor of each separately derived system be bonded to the metal water piping system?

A) Only at the point where the water pipe enters the building

B) At the utility transformer location

C) To the nearest accessible point of the metal water piping system(s) in the area served by each separately derived system

D) At the service equipment enclosure

60 / 80

60. If fuses are of the type that can be operated as a disconnecting switch, a set of such fuses shall be permitted to be used as what specific component in the service installation?

A) The short-circuit protective device

B) The isolating switch

C) The load interrupter

D) The transfer switch

61 / 80

61. In a multiple-occupancy building, service and feeder overcurrent protective devices supplying more than one occupancy shall be permitted to be accessible only to authorized management personnel, provided electric service and electrical maintenance are provided by the building management and under what supervision condition?

A) Continuous building management supervision

B) Remote supervision

C) Weekly inspection

D) Annual supervision

62 / 80

62. Branch circuits larger than 50 amperes shall supply only what type of outlet loads?

A) Continuous loads only

B) Nonlighting outlet loads

C) Only fixed equipment loads

D) Any utilization equipment load

63 / 80

63. A neutral conductor shall not be used for more than one branch circuit, for more than one multiwire branch circuit, or for how many sets of ungrounded feeder conductors?

A) Three

B) One

C) Unlimited, if sized properly

D) Two

64 / 80

64. Which rating is NOT required to be shown on a circuit breaker nameplate?

A) Interrupting rating in MVA or amperes

B) Ground-fault current setting

C) Continuous current rating

D) Maximum voltage rating

65 / 80

65. What demand factor percentage applies to the portion of general lighting load between 20,001 VA and 100,000 VA in a Hotel or Motel?

A) 55 percent

B) 50 percent

C) 35 percent

D) 60 percent

66 / 80

66. If a written record of Energy Storage System (ESS) maintenance is required, what must this record specifically include?

A) Fuel consumption logs and runtime hours

B) Daily logs of charge/discharge cycles

C) Annual inspection reports by the fire department

D) Records of repairs and replacements necessary to maintain the system in proper and safe operating condition

67 / 80

67. In dry board applications, heating cable must be installed parallel to the joist, leaving a clear space centered under the joist of what minimum width between centers of adjacent cable runs?

A) 1 1/2 in.

B) 3 in.

C) 2 1/2 in.

D) 2 in.

68 / 80

68. For conductors and live parts up to 22 kV or less to ground, what is the minimum horizontal clearance required from building walls, projections, and windows?

A) 1.8 m (6.0 ft)

B) 2.2 m (7.0 ft)

C) 2.0 m (6.5 ft)

D) 2.3 m (7.5 ft)

69 / 80

69. Conductors tapped to a feeder shall be permitted to be protected by the feeder overcurrent device where that device also protects what other component?

A) The tap conductor

B) The grounded conductor

C) The utilization equipment

D) The main service disconnect

70 / 80

70. Conductors of circuits rated over 1000 volts ac, 1500 volts dc, nominal, shall generally NOT occupy the same enclosure with conductors of circuits rated 1000 volts ac, 1500 volts dc, nominal, or less, unless otherwise permitted. True or False?

A) True

B) False

C) True, unless separated by a barrier

D) False, mixing is always permitted if insulated for the highest voltage

71 / 80

71. Adjustment factors shall not apply to conductors installed in raceways having a length not exceeding what maximum distance?

A) 300 mm (12 in.)

B) 600 mm (24 in.)

C) 1.8 m (6 ft)

D) 1.0 m (40 in.)

72 / 80

72. When auxiliary equipment for electric-discharge lamps is supplied by the ungrounded conductors of a circuit, the switching device must simultaneously disconnect all which conductors?

A) Grounded conductors

B) Equipment grounding conductors

C) Conductors

D) Neutral conductors

73 / 80

73. What type of thread is prohibited from being used on RMC for connection at couplings?

A) Straight threads

B) Standard taper threads

C) Machine threads

D) Running threads

74 / 80

74. When determining the electrical datum plane in land areas subject to storm-driven flooding, how high above the point identified as the prevailing high water mark must the horizontal plane be set?

A) 300 mm (1 ft)

B) 1.0 m (40 in.)

C) 750 mm (30 in.)

D) 600 mm (2 ft)

75 / 80

75. Which two hazards must be considered at a minimum during the Risk Assessment for Critical Operations Power Systems (COPS)?

A) Utility grid failures and internal equipment malfunction

B) System overloads and voltage sag

C) Solar flare activity and electromagnetic pulse (EMP)

D) Naturally occurring hazards and human-caused events (accidental and intentional)

76 / 80

76. Strut-type channel raceways are permitted as extensions through walls, partitions, and floors under what condition regarding access?

A) They must be sealed with concrete

B) Closure strips are removable from either side

C) The portion within the partition must be welded shut

D) Closure strips are removable only from the concealed side

77 / 80

77. Dry-type transformers 1000 Volts, nominal, or less, located in the open on walls, columns, or structures, shall not be required to be what?

A) Listed

B) Readily accessible

C) Accessible

D) Grounded

78 / 80

78. Motors rated less than 1/8 hp connected to a lighting circuit in a dwelling unit shall be considered part of what load?

A) The minimum lighting load

B) Appliance load

C) The continuous load

D) The motor-operated load

79 / 80

79. What size information is required to be marked on all IBP?

A) The metric designator

B) The outside diameter of the pipe

C) The internal diameter of the pipe

D) The equivalent AWG size or circular mil area of the conductor

80 / 80

80. PVC conduit is permitted for use in which two general types of locations, provided they are not prohibited by 352.12?

A) Dry and damp locations

B) Only damp locations

C) Wet and hazardous locations

D) Only dry locations

Your score is

2023 Commercial Electrical Inspector – Practice Quiz (Untimed)

“This untimed practice quiz simulates the ICC exam format, giving you full exposure to real-style questions while allowing unlimited time to navigate, learn, and build confidence without time pressure.”