Journeyman Electrician Practice Test 39

Question 1: What is the adjustment ampacity of a 3/0 THWN conductors in a wet location, if the raceway contains seven conductors in it?

• 122.5 amperes
• 125.5 amperes
• 140 amperes
• 133 amperes

NEC Reference: NEC Table 310.16

Question 2: A multifamily building has 12 household electric clothes dryers on one feeder. What demand factor applies under Table 220.54?

• 47%
• 46%
• 50%
• 55%

NEC Reference: NEC 220.54 and Table 220.54

Question 3: Under the 2023 NEC (Table 220.12), what is the general lighting unit load for a restaurant?

• 3 VA per sq ft
• 2 VA per sq ft
• 1.5 VA per sq ft
• 1 VA per sq ft

NEC Reference: NEC 220.12 and Table 220.12

Question 4: What is permissible voltage drop in percentage for combination of both feeders and branch circuit conductors?

• 2 %
• 3 %
• 5 %
• 8 %

NEC Reference: NEC 215.2(A)(1)

Question 5: How may screw-shell lampholders be used?

• As splice points
• As switches
• As receptacles for plug-in tools
• As lampholders only

NEC Reference: NEC 410.90

Question 6: What does a utility watt-hour (kWh) meter measure?

• Energy used over time
• The voltage drop on the service
• The power factor of the load
• Instantaneous current draw

Question 7: The length of a mobile home power-supply cord, measured from the face of the attachment plug to the point where it enters the mobile home, must be at least:

• 20 ft
• 21 ft
• 25 ft
• 36½ ft

NEC Reference: NEC 550.10(D)

Question 8: A device that converts AC input into pulsating DC output is called a __________.

• Rectifier
• Inverter
• clamper
• clipper

Question 9: May a thermal overload relay be used to protect conductors against short circuits and ground faults?

• Only on motor circuits
• No; it is not designed for faults
• Only under 600 V
• Yes, always

NEC Reference: NEC 240.9

Question 10: A lamp operating at 120 volts has a resistance of 480 ohms. What is the wattage of the lamp?

• 30 watts
• 25 watts
• 20 watts
• 0.25 watts

Question 11: A branch circuit supplies a continuous load. The grounded (neutral) conductor is not connected to any overcurrent device. How may the neutral be sized?

• At 80% of the load
• Always the same as the EGC
• At 125% of the continuous load, like the hot conductors
• At 100% of the continuous and noncontinuous load

NEC Reference: NEC 210.19(A)(1) Exception No. 2

Question 12: What type of device may serve as the service disconnecting means?

• A manually operable switch or breaker
• A fuse block with no switch
• Any plug and receptacle
• A contactor with no manual handle

NEC Reference: NEC 230.76

Question 13: NM cable feeds a luminaire in an accessible suspended ceiling. How far from its last support may it be left unsupported?

• 12 in.
• 2 ft
• 4½ ft
• 6 ft

NEC Reference: NEC 334.30(B)

Question 14: What limits the number and size of conductors in a raceway, beyond the fill tables?

• Nothing beyond the fill tables
• Only the insulation color code
• Only the voltage rating
• Heat dissipation and damage-free pulling

NEC Reference: NEC 300.17

Question 15: What backfill is NOT permitted in a trench where it could damage underground cables or raceways?

• Fine soil
• Clean sand
• Large rocks, cinders or sharp debris
• Screened native soil

NEC Reference: NEC 300.5(F)

Question 16: How must 3-way and 4-way switches be wired?

• Any way that works electrically
• Switching only in the ungrounded conductor
• With a separate neutral for each switch
• With switching done in the neutral

NEC Reference: NEC 404.2(A)

Question 17: Equipment is supplied by two separate circuits (for example, a unit with separate power and control supplies). How many EGCs are required?

• Only a ground rod
• One for both circuits
• None if one circuit is under 50 V
• An EGC for each circuit

NEC Reference: NEC 250.144

Question 18: Rigid PVC conduit is installed exposed in a location where it is subject to physical damage. What is required?

• PVC identified for the use
• It must be painted gray
• Any PVC may be used there
• PVC may never be exposed

NEC Reference: NEC 352.10(F)

Question 19: Several coordinated motor controllers drive parts of a single machine. May they share one controller disconnecting means?

• Only if each motor is under 1 hp
• Only if the disconnect is lockable
• Yes, one disconnect for the coordinated group
• No; each controller needs its own disconnect

NEC Reference: NEC 430.102(A) Exception No. 2

Question 20: What is required of recessed incandescent luminaires (other than those exempted)?

• A GFCI device
• Thermal protection, so identified
• Nothing special
• A dedicated circuit

NEC Reference: NEC 410.115(C)

Question 21: Under what atmospheric conditions and occupancies is rigid metal conduit (RMC) permitted?

• Only outdoors
• All conditions and occupancies
• Only dry locations
• Only in commercial buildings

NEC Reference: NEC 344.10(A)(1)

Question 22: The 6 ft wall receptacle spacing rule of 210.52(A) applies to which dwelling room?

• Hallways
• Bathrooms
• Garages
• Living rooms

NEC Reference: NEC 210.52(A)

Question 23: What is the minimum rating of a receptacle for a household electric range on an individual branch circuit?

• Based on single-range demand
• 30 A in every case
• Always 50 A
• Always equal to the breaker rating

NEC Reference: NEC 210.21(B)(4)

Question 24: A dual-fed (double-ended) service has a secondary tie between two power sources in a common enclosure. How may the grounding electrode conductor be connected?

• No GEC is required at all
• Only at the utility transformer
• One GEC to the grounded-conductor tie point
• At each source separately

NEC Reference: NEC 250.24(A)(3)

Question 25: In an existing dwelling, a 200 A panelboard is being replaced in a basement where the ceiling is only 6 ft 2 in. high. May the new panel be installed there?

• Only with a permit variance
• No; 6½ ft of headroom is always required
• Yes; 200 A or less in existing dwellings
• Only if it is rated 100 A or less

NEC Reference: NEC 110.26(A)(3)

Question 26: Per NEC 220.50, motor loads included in feeder and service load calculations shall be determined in accordance with _____ .

• The motor nameplate horsepower converted to watts
• NEC Article 430 (Parts II, IV, and V)
• NEC Table 220.12 unit load values
• The motor nameplate current rating directly

NEC Reference: NEC 220.50

Question 27: Kirchhoff's Current Law (KCL) states that at any junction (node) in a circuit, the sum of all currents entering the node must equal the sum of all currents _____ the node.

• Entering
• Leaving
• Bypassing
• Stored at

Question 28: For a panelboard installed outdoors, what is the dedicated equipment space?

• Only 3 ft in front
• Width and depth, grade to 6 ft above
• Up to the nearest tree
• There is none outdoors

NEC Reference: NEC 110.26(E)(2)

Question 29: How must main bonding jumpers and system bonding jumpers be connected?

• With electrical tape
• With solder only
• With sheet-metal screws
• As specified in 250.8

NEC Reference: NEC 250.28(C)

Question 30: In a multiple-occupancy building where the owner provides electrical maintenance under continuous building management supervision, who must have access to the service and feeder overcurrent devices?

• Authorized management staff only
• Every tenant
• No one at all
• The local fire department only

NEC Reference: NEC 240.24(B)(2)