Journeyman Electrician Practice Test 19

Question 1: At the service, what is the connection between the grounded circuit conductor and the equipment grounding conductor called?

• The main bonding jumper
• The grounding electrode conductor
• The equipment bonding jumper
• The system bonding jumper

NEC Reference: NEC Article 100

Question 2: A building has a rod electrode for its electrical system and separate rod electrodes for its lightning protection system. What is the minimum spacing between electrodes of the two systems?

• 2 ft
• 6 ft
• 8 ft
• 10 ft

NEC Reference: NEC 250.53(B)

Question 3: A grounding electrode conductor is installed in a steel (ferrous) raceway for protection. What is required?

• Increase the GEC one size to offset the steel
• Nothing more; the raceway itself protects it
• Paint the raceway green to identify it
• Bond the raceway to the GEC at each end

NEC Reference: NEC 250.64(E)

Question 4: A service has three parallel sets of 3/0 AWG copper ungrounded conductors. What is the minimum copper GEC to a metal underground water pipe electrode?

• 4 AWG
• 2 AWG
• 1/0 AWG
• 2/0 AWG

NEC Reference: NEC 250.66 and Table 250.66

Question 5: A transformer (separately derived system) has 250 kcmil copper secondary conductors, and metal water piping is in the area it serves. What size copper jumper bonds the SDS grounded conductor to the water piping?

• 1/0 AWG
• 2 AWG
• 4 AWG
• 6 AWG

NEC Reference: NEC 250.104(D)(1)

Question 6: A conductor with 0.5 Ω of resistance carries 20 A. What is the voltage drop across the conductor?

• 0.025 V
• 10 V
• 20.5 V
• 40 V

Question 7: A load draws 10 kVA at a power factor of 0.8. What is its true power?

• 12.5 kW
• 10 kW
• 8 kW
• 6 kW

Question 8: Three 10 kW, 208-volt heaters are connected line-to-line, one on each pair of lines, on a 208-volt, 3-phase system (balanced). What is the line current?

• 48.1 A
• 83.3 A
• 96.2 A
• 144.2 A

Question 9: In a dwelling unit, how many receptacle outlets are required, at minimum, in the area designated for laundry equipment?

• None
• One for each appliance
• Two
• One

NEC Reference: NEC 210.52(F)

Question 10: Overhead 120/240-volt conductors pass over a residential driveway. What is the minimum clearance above the driveway?

• 18 ft
• 15 ft
• 12 ft
• 10 ft

NEC Reference: NEC 225.18(2)

Question 11: Under the 2023 NEC, may a single panelboard without a main breaker, containing six 2-pole breakers, serve as the service disconnecting means?

• No; each needs its own enclosure or section
• Yes, but only for one-family dwelling services
• Yes; up to six breakers in one enclosure are allowed
• Yes, if the six breakers are grouped together

NEC Reference: NEC 230.71(B)

Question 12: Which of these installations is NOT covered by the NEC?

• Wiring in a floating building at a marina
• A customer-owned PV system on a house roof
• Wiring inside a manufactured mobile home
• Utility-owned generation on utility property

NEC Reference: NEC 90.2

Question 13: A panelboard marked "indoor use only" is installed in a building under construction before the roof is on. What does 110.11 require?

• Protect it from weather damage during construction
• Replace it with a NEMA 3R outdoor enclosure
• Leave it de-energized until the roof is complete
• Nothing until the building is fully finished

NEC Reference: NEC 110.11

Question 14: The available fault current at a panelboard is 18,000 A. Which is the smallest of these breaker interrupting ratings permitted?

• 10,000 A
• 14,000 A
• 22,000 A
• 65,000 A

NEC Reference: NEC 110.9

Question 15: At each outlet or junction box, at least how much free conductor must be left for splices or connections?

• 3 in.
• 6 in.
• 8 in.
• 12 in.

NEC Reference: NEC 300.14

Question 16: A 2-wire cable with a white conductor is used as a switch loop. How may the re-identified white conductor be used?

• As the switched return conductor to the light
• As the equipment grounding conductor of the loop
• As the grounded (neutral) conductor only
• Only as the supply to the switch

NEC Reference: NEC 200.7(C)(1)

Question 17: A 3 AWG THWN copper conductor (75 °C) runs where the ambient temperature is 45 °C, with three current-carrying conductors in the raceway. What is its corrected ampacity?

• 71 A
• 82 A
• 87 A
• 100 A

NEC Reference: NEC 310.15(B)(1)(1) and Table 310.16

Question 18: How must enclosures for overcurrent devices normally be mounted?

• Vertically, unless that is impracticable
• Face-up on the floor or on a housekeeping pad
• At any angle the installer chooses
• Horizontally, with the handles facing upward

NEC Reference: NEC 240.33

Question 19: A 480-volt to 208-volt transformer is protected on the primary by a 100 A breaker. Under the 25 ft secondary conductor rule, what is the minimum ampacity of the secondary conductors?

• 230.8 A
• 100 A
• 76.9 A
• 33.3 A

NEC Reference: NEC 240.21(C)(6)

Question 20: How is the direction of rotation of a 3-phase induction motor reversed?

• Rotate all three line leads one position
• Reverse the field and the armature leads
• Reverse the leads of the starting capacitor
• Swap any two of the three line leads

Question 21: A 10 hp, 230-volt, 3-phase motor will not start on time-delay (dual-element) fuses sized at 175%. What is the maximum time-delay fuse permitted under Exception No. 2(b)?

• 50 A
• 60 A
• 70 A
• 80 A

NEC Reference: NEC 430.52(C)(1) Exception No. 2(b) and Table 430.250

Question 22: An indoor hot tub requires at least one 125-volt, 15- or 20-ampere general-purpose receptacle. Where must it be located, measured from the inside wall of the hot tub?

• Not less than 6 ft and not more than 10 ft
• Within 5 ft
• Anywhere in the room
• Not less than 10 ft and not more than 20 ft

NEC Reference: NEC 680.43(A)

Question 23: How must boxes and enclosures for emergency circuits be identified?

• Permanently marked as emergency system parts
• Marked only on the building's electrical drawings
• No marking is required if they are in a locked room
• Painted green so they stand out from normal ones

NEC Reference: NEC 700.10(A)

Question 24: A new RV park has 40 sites with electrical supply. Under the 2023 NEC, at least how many sites must have a 50-ampere, 125/250-volt receptacle?

• 8
• 12
• 16
• 28

NEC Reference: NEC 551.71

Question 25: On a construction site, when may splices in temporary wiring be made without a box?

• Never; every splice needs a box
• Whenever the circuit has GFCI protection
• When the splice is wrapped with electrical tape
• When all are nonmetallic cord or cable assemblies

NEC Reference: NEC 590.4(G)

Question 26: A gas furnace has electric controls and a blower. How must it be supplied?

• By an individual branch circuit
• From any general-purpose lighting circuit
• From the laundry circuit
• From the small-appliance circuit

NEC Reference: NEC 422.12

Question 27: A 25 ft metal pole supports parking-lot luminaires. What is the minimum handhole size for access to the supply terminations?

• 1 in. × 2 in.
• 2 in. × 4 in.
• 4 in. × 6 in.
• 6 in. × 8 in.

NEC Reference: NEC 410.30(B)(1)

Question 28: An EMT run between two pull boxes has four 90° bends and one 45° offset (two 22½° bends). Does it comply with 358.26?

• Yes; there is no limit on bends in EMT
• Yes; offsets are not counted toward the limit
• No; the bends total 405°, over the 360° limit
• No; EMT may have only two bends per run

NEC Reference: NEC 358.26

Question 29: An outlet box with no enclosed devices or utilization equipment must have an internal depth of at least:

• ½ in.
• ¾ in.
• 1 in.
• 1½ in.

NEC Reference: NEC 314.24(A)

Question 30: Where separate EGCs and supply-side bonding jumpers terminate in a dry-type transformer enclosure, what does 450.10(A) require?

• A separate grounding enclosure beside the unit
• A ground rod driven next to the transformer
• All of them landed on one lug bolted to the core
• A terminal bar inside it, not over any vents

NEC Reference: NEC 450.10(A)