Journeyman Electrician Practice Test 7

Question 1: Metal gas piping in a house is likely to become energized by the gas furnace, which is supplied by a 20-ampere branch circuit. What is the minimum size copper bonding conductor for the gas piping?

• 6 AWG
• 8 AWG
• 12 AWG
• 14 AWG

NEC Reference: NEC 250.104(B)

Question 2: A building is supplied by two services. What does the NEC require for their grounding electrodes?

• The same grounding electrode system must be used for both services
• Each service needs its own pair of rods at least 25 ft apart
• Each service must have a completely separate grounding electrode system
• Only one of the services is required to be grounded

NEC Reference: NEC 250.58

Question 3: An equipment grounding conductor is being added for a replacement grounding-type receptacle on an existing branch circuit without an EGC. Which connection point is NOT permitted?

• A metal cold water pipe in the bedroom wall, 30 ft from where it enters the building
• The EGC terminal bar in the panelboard where the circuit originates
• Any accessible point on the grounding electrode system
• The EGC of another branch circuit originating from the same panelboard

NEC Reference: NEC 250.130(C)

Question 4: "Objectionable current" on equipment grounding conductors and metal raceways is most commonly caused by:

• Installing GFCI protection on a branch circuit that also has an EGC
• Using aluminum rather than copper for the equipment grounding conductors
• Sizing the grounding electrode conductor one size larger than required
• Connecting the neutral to the EGC at more than one point, such as a subpanel

NEC Reference: NEC 250.6

Question 5: According to 250.4(A)(5), may the earth be considered an effective ground-fault current path?

• Yes, provided the ground rod measures less than 25 ohms to earth
• Yes, but only for circuits operating at 150 V or less to ground
• Only where the soil around the electrode stays dry all year
• No, the earth is not to be considered an effective fault current path

NEC Reference: NEC 250.4(A)(5)

Question 6: A multifamily building has six household electric clothes dryers rated 5.5 kW each. What is the dryer demand load for the service?

• 19.8 kW
• 24.75 kW
• 30.0 kW
• 33.0 kW

NEC Reference: NEC 220.54 and Table 220.54

Question 7: A dwelling has three counter-mounted cooking units rated 6 kW each. Using Column B of Table 220.55, what is the demand load?

• 18.0 kW
• 14.0 kW
• 9.9 kW
• 8.0 kW

NEC Reference: NEC Table 220.55, Column B

Question 8: A 120-volt, 20-ampere load is 75 ft from the panel, supplied by 12 AWG copper (6,530 cmil, K = 12.9). What is the approximate voltage drop as a percentage?

• 2.5%
• 3.0%
• 4.9%
• 9.9%

NEC Reference: NEC Chapter 9, Table 8

Question 9: In an existing dwelling, a bedroom branch circuit is extended 15 ft to add a new receptacle outlet. What does the NEC require?

• AFCI: combination type at the origin, or OBC type at the first outlet
• A new home run to the panelboard for the added receptacle only
• A GFCI receptacle at the new outlet; no other protection is needed
• Nothing; existing branch circuits are exempt from the AFCI rules

NEC Reference: NEC 210.12(D)

Question 10: A service supplies 150 A of continuous load and 50 A of noncontinuous load. What minimum ampacity must the service-entrance conductors have?

• 250 A
• 237.5 A
• 212.5 A
• 200 A

NEC Reference: NEC 230.42(A)(1)

Question 11: A building has both 480Y/277-volt and 208Y/120-volt feeders. How must the ungrounded feeder conductors be identified?

• By phase and system at each termination and splice point
• Only by using the same colors that are used for the branch circuits
• Only at the service equipment, not at any downstream panelboard
• No identification is required for feeder conductors in any building

NEC Reference: NEC 215.12(C)(1)

Question 12: For an indoor panelboard, the dedicated electrical space directly above it (equal to its width and depth) extends to what height?

• 10 ft above the floor, regardless of the ceiling height
• 3 ft above the panelboard, or to the ceiling if it is lower
• The full height of the room in every case, including above it
• 6 ft above the panelboard, or to the structural ceiling if lower

NEC Reference: NEC 110.26(E)(1)(a)

Question 13: Article 100 defines a "qualified person" as one who:

• Holds any state or local electrical license or permit
• Has worked for at least two years in the electrical trade
• Is employed by the serving utility or an electrical contractor
• Has the skills, knowledge and safety training for the task

NEC Reference: NEC Article 100

Question 14: What is the capacitive reactance of a 100 µF capacitor in a 60 Hz circuit?

• 3.77 Ω
• 26.5 Ω
• 37.7 Ω
• 265 Ω

Question 15: A one-family dwelling has a 100-ampere service. Using Table 310.12, what is the minimum size aluminum service-entrance conductor?

• 4 AWG
• 3 AWG
• 2 AWG
• 1/0 AWG

NEC Reference: NEC Table 310.12

Question 16: Direct-buried conductors emerging from grade must be protected by enclosures or raceways extending from the minimum cover depth below grade to at least what height above finished grade?

• 3 ft
• 6 ft
• 8 ft
• 10 ft

NEC Reference: NEC 300.5(D)(1)

Question 17: Where 4 AWG or larger insulated conductors enter a cabinet or box from a raceway, the conductors must be protected by:

• An identified fitting with a smoothly rounded insulating surface
• A sealing fitting filled with listed compound at the entry
• A standard steel locknut tightened against the enclosure wall
• Two wraps of electrical tape around the conductors at the entry

NEC Reference: NEC 300.4(G)

Question 18: A 480-volt to 208-volt transformer is protected on the primary by a 100 A breaker. Secondary conductors not over 10 ft long leave the transformer enclosure (field installation). Apart from the load they serve, what minimum ampacity must they have?

• 10.0 A
• 23.1 A
• 43.3 A
• 100 A

NEC Reference: NEC 240.21(C)(2)

Question 19: Supplementary overcurrent protection, such as a fuse inside a luminaire, is:

• Not a substitute for branch-circuit protection; need not be readily accessible
• A permitted substitute for the branch-circuit overcurrent device
• Required to be rated at least 125% of the branch-circuit rating
• Required to be readily accessible from the floor without a ladder

NEC Reference: NEC 240.10

Question 20: An instantaneous trip circuit breaker (motor circuit protector) used for a typical AC induction motor (not Design B energy-efficient premium) may be set at a maximum of what percentage of the motor full-load current?

• 250%
• 300%
• 800%
• 1,100%

NEC Reference: NEC Table 430.52

Question 21: A 460-volt, 3-phase feeder supplies a 20 hp motor (27 A), a 10 hp motor (14 A) and a 30 A continuous resistance heating load. What is the minimum feeder ampacity?

• 88.75 A
• 85.25 A
• 77.75 A
• 71.0 A

NEC Reference: NEC 430.24

Question 22: An electric vehicle supply equipment (EVSE) unit has a maximum load of 48 A. What is the minimum rating of the branch-circuit overcurrent device?

• 48 A
• 50 A
• 60 A
• 70 A

NEC Reference: NEC 625.41

Question 23: An optional standby generator is connected to a building wiring system that is also supplied by the utility. What is required?

• Only a lockable circuit breaker mounted at the generator itself
• A separate ground rod at the generator, bonded to building steel
• Nothing; a double-throw transfer switch is optional for these systems
• Transfer equipment that prevents interconnecting the two sources

NEC Reference: NEC 702.5

Question 24: Which wiring method is NOT permitted in a Class I, Division 1 location?

• EMT with compression fittings
• Threaded rigid metal conduit
• Threaded steel intermediate metal conduit
• Type MI cable with listed termination fittings

NEC Reference: NEC 501.10(A)(1)

Question 25: Temporary electric power and lighting for holiday decorative lighting is permitted for a period not to exceed:

• 180 days
• 90 days
• 60 days
• 30 days

NEC Reference: NEC 590.3(B)

Question 26: A 15-ampere receptacle installed outdoors in a damp location (under a covered porch) must have an enclosure that is weatherproof:

• At all times, including while an attachment plug is inserted
• Only if it is mounted more than 5½ ft above the porch floor
• Only when the receptacle is also protected by a GFCI device
• When the receptacle is covered, with no plug inserted and covers closed

NEC Reference: NEC 406.9(A)

Question 27: Which luminaire may be installed directly above a bathtub, within the zone 3 ft horizontally and 8 ft vertically from the top of the tub rim?

• A cord-suspended pendant luminaire with an enclosed globe
• A recessed luminaire marked suitable for damp (or wet) locations
• A section of lighting track with enclosed track heads
• A ceiling-suspended (paddle) fan with an integral light kit

NEC Reference: NEC 410.10(D)

Question 28: For box fill, how is an unbroken conductor that is looped inside the box counted when it is at least 12 in. long?

• As two conductors
• It is not counted
• As three conductors
• As one conductor

NEC Reference: NEC 314.16(B)(1)

Question 29: After EMT is cut, what must be done to the cut ends?

• They must be threaded before any fitting is installed
• They must be painted with zinc-rich paint to prevent rust
• Nothing, provided listed compression fittings are used
• They must be reamed or finished to remove rough edges

NEC Reference: NEC 358.28(A)

Question 30: A 30 kVA, 3-phase transformer has a 480-volt primary. Both primary and secondary overcurrent protection are provided (secondary at 125%). What is the maximum standard primary overcurrent device rating?

• 45 A
• 70 A
• 90 A
• 100 A

NEC Reference: NEC Table 450.3(B)