2023 Commercial Electrical Inspector – Practice Quiz (Untimed)

2023 Commercial Electrical Inspector (Untimed)

80 Questions

3.5 Hours

1 / 80

1. If a feeder supplies 55 dwelling units in a multifamily dwelling, what demand factor percentage applies using the optional method (Table 220.84(B))?

A) 25 percent

B) 24 percent

C) 25 percent

D) 26 percent

2 / 80

2. A location adjacent to a Zone 20 location may be classified as Zone 21, unless communication from the Zone 20 location is minimized by adequate positive pressure ventilation from a source of clean air and what else?

A) Continuous monitoring by personnel

B) The door is self-closing

C) Effective safeguards against ventilation failure are provided

D) Explosionproof barriers are installed

3 / 80

3. What must activate the damper operation of an HVAC system serving other occupancies that also serves the information technology equipment room?

A) Smoke detector alarms, operation of the disconnecting means required by 645.10, or both

B) Loss of power to the HVAC unit

C) Manual switch located at the building entrance

D) HVAC unit high-temperature alarm

4 / 80

4. Cables with entirely nonmetallic sheaths entering the top of a surface-mounted enclosure through nonflexible raceways (Exception No. 1) must ensure the raceway length is not more than what maximum distance?

A) 1.8 m (6 ft)

B) 2.5 m (8 ft)

C) 3.0 m (10 ft)

D) 3.0 m (10 ft)

5 / 80

5. What is the minimum required rating for the service disconnecting means supplying a one-family dwelling?

A) 60 amperes, 3-wire

B) 100 amperes, 2-wire

C) 60 amperes, 2-wire

D) 100 amperes, 3-wire

6 / 80

6. Equipment having an open-circuit voltage exceeding 300 Volts shall not be installed in dwelling occupancies unless designed so that there will be no exposed live parts during which three actions?

A) Servicing, maintenance, or testing

B) Installation, repair, or inspection

C) Operation, standby, or de-energized

D) Lamp insertion, lamp in place, or lamp removal

7 / 80

7. Which of the following is NOT a permitted wiring method in ducts specifically fabricated to transport environmental air?

A) Intermediate metal conduit (IMC)

B) Electrical nonmetallic tubing (ENT)

C) Type MI cable without an overall nonmetallic covering

D) Rigid metal conduit (RMC) without an overall nonmetallic covering

8 / 80

8. Where buildings exceed three stories or 15 m (50 ft) in height, overhead lines shall be arranged, where practicable, to leave a clear space (or zone) of at least what minimum width?

A) 2.5 m (8 ft)

B) 1.8 m (6 ft)

C) 2.0 m (6 1/2 ft)

D) 1.5 m (5 ft)

9 / 80

9. Free nonheating leads of cables must be installed from the junction box to a location within the ceiling using which wiring methods?

A) Exposed armored cable

B) Type TC cable

C) Flexible cord

D) Chapter 3 wiring methods, or other listed means

10 / 80

10. The size of the DC system bonding jumper shall not be smaller than what conductor?

A) The system grounding electrode conductor specified in 250.166

B) The largest derived ungrounded conductor

C) 4 AWG copper

D) The neutral conductor

11 / 80

11. 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) 501.10(A) and 504.10(B)

C) 362.10(8) and 300.5

D) 410.117(C) and 518.4

12 / 80

12. Horizontal runs of LFMC supported by openings through framing members shall be permitted if the support intervals do not exceed what maximum distance?

A) 1.8 m (6 ft)

B) 1.2 m (4 ft)

C) 1.4 m (4 1/2 ft)

D) 0.9 m (3 ft)

13 / 80

13. For PVC conduit installed in wet locations, what is required for all supports, bolts, straps, screws, and so forth?

A) They must be galvanized steel

B) They shall be nonmetallic only

C) They shall be of corrosion-resistant materials or be protected against corrosion by approved corrosion-resistant materials

D) They must be embedded in concrete

14 / 80

14. Where service heads or goosenecks cannot be located above the point of attachment of the service conductors, the service head or gooseneck location shall be permitted not farther than what maximum distance from the point of attachment?

A) 600 mm (24 in.)

B) 1.2 m (4 ft)

C) 900 mm (36 in.)

D) 450 mm (18 in.)

15 / 80

15. What is the ampacity for 4/0 AWG copper single-insulated conductor in free air, Type RHH, installed in a 30°C ambient temperature?

A) 405 amperes

B) 300 amperes

C) 405 amperes

D) 360 amperes

16 / 80

16. What is the minimum wire-bending space and minimum gutter space required in switchboards, switchgear, and panelboards?

A) As determined by the manufacturer

B) As required in 312.6

C) As required by the wire size

D) 6 in. or more

17 / 80

17. If trade size designators are used, when is it required to use dimensions instead of the trade size?

A) When the product is listed

B) When the measurement is in SI units

C) When installing rigid metal conduit

D) Trade size designators shall be used rather than dimensions where the actual measured size is not the same as the nominal size

18 / 80

18. Cable trays used to support service-entrance conductors shall contain only service-entrance conductors unless what is installed?

A) A continuous metallic shield

B) A fire-rated divider

C) A solid fixed barrier identified for use with the cable tray

D) A cable tray cover

19 / 80

19. Which piece of information is explicitly required to be marked on the surface of Type SHD-GC portable power feeder cables?

A) The number of conductor strands

B) The ambient temperature rating

C) The AWG size or circular mil area

D) The date of manufacture

20 / 80

20. PVC conduit is generally prohibited in theaters and similar locations, except as provided in which two specific sections?

A) 352.10(H) and 300.5

B) 501.10(A) and 504.10(B)

C) 518.4 and 520.5

D) 410.117(C) and 518.4

21 / 80

21. The first 60 amperes of the load for a farm building (other than the dwelling unit) shall be calculated at what percentage, if it is the largest of the simultaneous loads or 125 percent of the largest motor?

A) 75 percent

B) 25 percent

C) 50 percent

D) 100 percent

22 / 80

22. What is the minimum conductor size permitted within a listed component or as part of the wiring of a listed assembly?

A) 30 AWG

B) 18 AWG

C) 24 AWG

D) 26 AWG

23 / 80

23. Service raceways exposed to the weather must be arranged to drain and must be listed or approved for use in which type of location?

A) Wet locations

B) Hazardous locations

C) Dry locations

D) Damp locations

24 / 80

24. Thermal protection is not required for a recessed incandescent luminaire if it is identified for use and installed in what specific material?

A) Wood framing

B) Suspended ceilings

C) Metal stud walls

D) Poured concrete

25 / 80

25. What is the minimum required clearance for overhead spans of open conductors above the track rails of railroads?

A) 7.0 m (23 ft)

B) 8.5 m (28 ft)

C) 6.0 m (20 ft)

D) 7.5 m (24 1/2 ft)

26 / 80

26. For indoor electrical equipment, which enclosure type provides protection against falling dirt and incidental contact but does NOT provide protection against falling liquids?

A) Type 2

B) Type 5

C) Type 1

D) Type 12

27 / 80

27. Other outlets not specifically covered in 220.14(A) through (J) shall be calculated based on how many volt-amperes per outlet?

A) 120 volt-amperes

B) 180 volt-amperes

C) 300 volt-amperes

D) 90 volt-amperes

28 / 80

28. Retrofit trip units must be listed for use with what specific component?

A) The panelboard manufacturer

B) The feeder conductor size

C) The specific circuit breaker with which it is installed

D) The supply voltage

29 / 80

29. Each length of IMC shall be clearly and durably marked at least every what maximum distance with the letters IMC?

A) 3.0 m (10 ft)

B) 1.5 m (5 ft)

C) 1.2 m (4 ft)

D) 0.9 m (3 ft)

30 / 80

30. Insulated conductors or cables exposed to direct rays of the sun must be listed as being what?

A) Fire-retardant

B) Suitable for wet locations

C) Sunlight resistant

D) UV resistant

31 / 80

31. What is the maximum interval permitted for securing LFNC when installed in lengths exceeding 1.8 m (6 ft)?

A) 900 mm (3 ft)

B) 1.4 m (4 1/2 ft)

C) 1.2 m (4 ft)

D) 600 mm (2 ft)

32 / 80

32. What restriction applies to supporting, terminating, or connecting metal raceways by welding?

A) Permitted only on rigid metal conduit (RMC)

B) Permitted only for grounding connections

C) Permitted only under engineering supervision

D) Prohibited unless specifically designed to be or otherwise specifically permitted in this Code

33 / 80

33. For a new restaurant that is NOT all-electric and has a total connected load of 900 kVA, what is the required calculated load (kVA)?

A) 496.3 kVA

B) 516.3 kVA

C) 900.0 kVA

D) 500.0 kVA

34 / 80

34. For connections within an accessible ceiling to luminaire(s) or other equipment, what is the maximum length of unsecured ENT permitted from the last point where the raceway is securely fastened?

A) 3.0 m (10 ft)

B) 0.9 m (3 ft)

C) 1.8 m (6 ft)

D) 1.2 m (4 ft)

35 / 80

35. What must corrosion protection maintain for the ferromagnetic envelope in skin-effect heating systems?

A) The external paint color

B) The high-temperature rating

C) The original wall thickness of the ferromagnetic envelope

D) A minimum 50 (mm)spacing

36 / 80

36. In urban water-pipe areas, if the grounded conductor has at least four water-pipe connections, the metal interconnection shall be permitted to be made to the secondary neutral conductor with omission of what direct connection?

A) The direct grounding connection at the surge arrester

B) The nearest bonding jumper

C) The connection to the transformer case

D) The secondary circuit grounding electrode

37 / 80

37. What is the maximum weight a ceiling-suspended (paddle) fan shall be permitted to weigh when supported solely by an outlet box or outlet box system?

A) 16 kg (35 lb)

B) 23 kg (50 lb)

C) 32 kg (70 lb)

D) 27 kg (60 lb)

38 / 80

38. What demand factor percentage applies when calculating the load for 10 shore power receptacles in a marina (Table 220.120)?

A) 80 percent

B) 85 percent

C) 90 percent

D) 70 percent

39 / 80

39. Flexible cords are permitted in show windows and showcases as supply cords for portable luminaires and other displayed merchandise, or for which other wiring use?

A) Temporary lighting for construction

B) The main service power connection

C) The wiring of fixed equipment

D) The wiring of chain-supported luminaires

40 / 80

40. Securing or supporting of LFNC is NOT required when installed in lengths not exceeding what distance at terminals where flexibility is required?

A) 900 mm (3 ft)

B) 1.8 m (6 ft)

C) 1.2 m (4 ft)

D) 600 mm (2 ft)

41 / 80

41. For tap conductors not over 3 m (10 ft) long, the ampacity of the tap conductors shall be not less than the rating of the equipment containing an overcurrent device(s) supplied by the tap conductors OR not less than the rating of what device?

A) The main service disconnect

B) The primary transformer OCPD

C) The overcurrent protective device at the termination of the tap conductors

D) The feeder overcurrent device

42 / 80

42. Which parts of Article 706 must flow battery Energy Storage Systems (ESS) also meet, in addition to Part V requirements?

A) Parts III, IV, and VI

B) Parts I, IV, and VI

C) Parts I, II, and III of this article

D) Parts II, IV, and VI

43 / 80

43. An SPD shall not be installed on ungrounded systems unless listed specifically for use on which systems?

A) Any system with a single point ground

B) Any system over 480 volts

C) Only solidly grounded wye systems

D) Ungrounded systems, impedance grounded systems, or corner grounded delta systems

44 / 80

44. What function must an SPD provide to show that it is operational?

A) A visual display of surge counts

B) Indication that it is functioning properly

C) An audible alarm

D) Remote monitoring

45 / 80

45. A box or conduit body is NOT required for splices and taps in direct-buried conductors and cables, as permitted by which section?

A) 300.4(A)

B) 334.40(B)

C) 314.16(C)

D) 300.5(E)

46 / 80

46. If a Power Source output connection is made to a feeder at a location other than the opposite end from the primary source overcurrent device, what is one method to protect the portion of the feeder on the load side of the connection?

A) The feeder must be protected by a GFDI device.

B) The feeder ampacity shall be 100 percent of the power-source output current.

C) The feeder ampacity shall be not less than the sum of the rating of the primary source overcurrent device and 125 percent of the power-source output circuit current.

D) An overcurrent device rated not greater than the primary source OCPD rating is installed.

47 / 80

47. In tunnel installations over 1000 volts, how must electrical controls for the ventilation system be arranged?

A) So that the airflow can be reversed

B) To automatically shut off upon fault detection

C) To be readily accessible at the portal

D) To interface with the fire alarm system

48 / 80

48. Cell line conductors must be joined by which of the following connection methods?

A) Bolted, welded, clamped, or compression connectors

B) Wire nuts or twist-on connectors

C) Split bolt connectors only

D) Only soldering

49 / 80

49. Splicing of a wire-type grounding electrode conductor is permitted only by irreversible compression-type connectors listed as grounding and bonding equipment or by what other method?

A) High-heat soldering

B) Bolted connections

C) Exothermic welding process

D) Threaded couplings

50 / 80

50. Where the generator disconnecting means is located within the generator behind a hinged cover, door, or enclosure panel, what must be provided?

A) A field applied label meeting the requirements of 110.21(B) indicating the location of the generator disconnecting means

B) A warning sign rated 480Volts

C) A dedicated light source

D) A manual override switch

51 / 80

51. A system or circuit conductor that is intentionally grounded is defined as the:

A) Grounded Conductor

B) Equipment Grounding Conductor

C) Supply-Side Bonding Jumper

D) Bonding Jumper

52 / 80

52. In prewiring for air-conditioning installation in a recreational vehicle, the prewire circuit shall terminate in a junction box with a blank cover or other listed enclosure, and the ampere rating marked on the safety label shall not exceed what percentage of the circuit rating?

A) 100 percent

B) 125 percent

C) 75 percent

D) 80 percent

53 / 80

53. The disconnecting means for the normal power source of a fire pump shall not be located within the same enclosure, panelboard, or switchboard that supplies what type of loads?

A) Feeder taps

B) Optional standby loads

C) Loads other than the fire pump

D) Emergency loads

54 / 80

54. Solar PV systems with PV system DC circuits operating at 80 volts DC or greater between any two conductors shall be protected by what listed device?

A) Listed ground-fault protection device

B) Listed rapid shutdown controller

C) Listed surge protective device

D) Listed PV arc-fault circuit interrupter or other system components listed to provide equivalent protection

55 / 80

55. Underground cables and conductors installed under a building must be installed in what wiring method?

A) Rigid polyvinyl chloride conduit (PVC)

B) Intermediate metal conduit (IMC)

C) Rigid metal conduit (RMC)

D) A raceway

56 / 80

56. Dispensing devices for LP-Gas must be located at least what minimum distance from any dispensing device for Class I liquids, unless certain conditions regarding low release volume are met?

A) 5 ft.

B) 20 ft.

C) 6ft 7in

D) 10 ft.

57 / 80

57. Flexible cords and cables used to connect moving parts of Power Production Equipment must be listed and identified as DG cable or what other specific requirement?

A) Type THHN/THWN conductors

B) Other cable suitable for extra hard use, and shall be water resistant.

C) Type TC-ER cable

D) Type NM or UF cable

58 / 80

58. How often must exposed cable or raceway systems be permanently marked to identify them as a component of an Emergency System circuit?

A) At every pull box

B) At 9.0 m (30 ft) intervals

C) At intervals not to exceed 7.6 m (25 ft)

D) At 6.0 m (20 ft) intervals

59 / 80

59. 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) They must be flush with the outer surface.

B) 10 mm (3/8 in.)

C) 3 mm (1/8 in.)

D) 6 mm (1/4 in.)

60 / 80

60. For over 1000Volts installations, parts that must be removed for lamp replacement shall be hinged or what other condition applies?

A) Rated for 15,000Volts

B) Listed for wet locations

C) Held captive

D) Constructed of nonmetallic material

61 / 80

61. EMT shall not be used for the support of luminaires or other equipment, except for what?

A) Conduit bodies no larger than the largest trade size of the tubing

B) Only device boxes

C) Conduit bodies no larger than metric designator 12 (trade size 3/8)

D) Lightweight flexible conduit bodies

62 / 80

62. Where resistance-type boilers are rated 50(kW) or more, the conductors supplying the supplementary overcurrent protective devices can be sized at 100 percent of the nameplate rating if what type of device controls the cyclic operation?

A) A low-water cutoff

B) A magnetic starter

C) A temperature- or pressure-actuated device

D) An instantaneous trip breaker

63 / 80

63. Portable power feeder cables rated from 2000Volts to 5000Volts shall not be bent to a radius less than how many times the overall cable outer diameter?

A) Six times

B) Ten times

C) Four times

D) Eight times

64 / 80

64. A separate leakage test device shall not be required where the shore power equipment includes which features?

A) A leakage indicator and leakage alarm

B) A manual testing switch

C) GFCI protection rated at 5 mA

D) An automatic fault shutdown system

65 / 80

65. Equipment intended to interrupt current at fault levels must have an interrupting rating at nominal circuit voltage at least equal to what?

A) The continuous load current

B) The current that must be interrupted

C) 150 percent of the largest overcurrent device

D) The available fault current at the line terminals of the equipment

66 / 80

66. Horizontal runs of LFNC supported by openings through framing members shall be permitted if the support intervals do not exceed what maximum distance?

A) 1.8 m (6 ft)

B) 600 mm (2 ft)

C) 1.2 m (4 ft)

D) 900 mm (3 ft)

67 / 80

67. If equipment and conductors are connected to more than one electrical source in a fuel cell system installation, what protection is required?

A) They must be continuously monitored.

B) They must be installed in separate raceways.

C) They shall be protected against overcurrent.

D) They must be isolated by a transformer.

68 / 80

68. When installing Class 2 and Class 3 Circuit conductors in enclosures with electric light or power circuits, what minimum separation distance must be maintained if voltage is not 150 volts or less to ground?

A) A minimum of 50 mm (2 in.) separation

B) A minimum of 6 mm (0.25 in.) separation

C) Separation is not required if connected to associated equipment

D) A continuous fixed nonconductor barrier

69 / 80

69. When using a common grounding electrode conductor for multiple separately derived systems, how must tap connections be made to the common GEC?

A) Using bolted busbar connections only

B) In a manner such that the common grounding electrode conductor remains without a splice or joint

C) By splicing the common GEC

D) Using solder connections

70 / 80

70. 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) A service mast coupling

B) The utility pole

C) The building or other structure

D) The neutral bus

71 / 80

71. Barber shops and beauty parlors are considered similar to what occupancy type for lighting load calculations in Table 220.42(A)?

A) Workshop

B) Health care clinic

C) Retail

D) Office

72 / 80

72. For fixed multioutlet assemblies in commercial occupancies where appliances are unlikely to be used simultaneously, each 1.5 m (5 ft) or fraction thereof shall be considered as one outlet of not less than how many volt-amperes?

A) 90 volt-amperes

B) 150 volt-amperes

C) 120 volt-amperes

D) 180 volt-amperes

73 / 80

73. What is the minimum wire-bending space required in an enclosure for a single 1/0 AWG wire per terminal, measured in a straight line from the end of the lug?

A) 6 in.

B) 5 in.

C) 3 in.

D) 4 in.

74 / 80

74. What is the required color identification for Isolated Conductor No. 2 in an isolated power circuit?

A) Yellow with a distinctive stripe

B) White with a distinctive stripe

C) Orange with a distinctive stripe

D) Brown with a distinctive stripe

75 / 80

75. When applying demand factors from Table 220.45, they shall apply to the total branch-circuit load calculated for general illumination but shall NOT be applied when determining what?

A) The total connected VA load

B) The feeder neutral size

C) The number of branch circuits for general illumination

D) The continuous load multiplier

76 / 80

76. Which of the following occupancies requires a surge-protective device (SPD) to be provided for all services supplying it?

A) Office spaces

B) Dormitory units

C) Commercial kitchens

D) Schools

77 / 80

77. For a dc feeder system operating at 120 volts, how must a positive ungrounded conductor of 4 AWG be identified at all termination, connection, and splice points?

A) By polarity using only a continuous red outer finish

B) By using white insulation with a red stripe

C) By continuous black insulation

D) By polarity using marking tape, tagging, or other approved means

78 / 80

78. If multiple grounding connections result in objectionable current, and the effective ground-fault current path requirements are met, which remedial action is permitted?

A) Discontinue all grounding or bonding connections

B) Install a listed isolator device

C) Increase the size of the grounding electrode conductor

D) Discontinue one or more but not all of such grounding or bonding connections

79 / 80

79. The equipment grounding conductor of the supply circuit shall be permitted to serve as the bonding means if the metal frames or parts are likely to become energized in the event of what?

A) Overload

B) Short circuit

C) Overvoltage

D) Fault

80 / 80

80. For indoor electrical equipment, which enclosure type is suitable for protection against hosedown and splashing water, temporary submersion, and falling dirt, but NOT against corrosive agents?

A) Type 12K

B) Type 6

C) Type 3R

D) Type 4X

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.”