Journeyman Electrician Practice Test 11

Question 1: Which of these AC systems is required to be grounded?

• A 208Y/120 V, 3-phase, 4-wire wye with neutral loads
• A 600 V, 3-phase, 3-wire delta used only for heaters
• A 480 V, 3-phase, 3-wire delta used only for motors
• A 240 V, 3-phase, 3-wire delta used only for motors

NEC Reference: NEC 250.20(B)

Question 2: A metal underground water pipe qualifies as a grounding electrode. What else does the NEC require?

• Nothing; it is permitted to be the only electrode
• It must be bonded only at the water heater
• It must be at least 2 in. in trade diameter
• It must be supplemented by another electrode

NEC Reference: NEC 250.53(D)(2)

Question 3: The water pipe grounding electrode connection is made on the street side of a water meter. What is required at the meter?

• A dielectric union to isolate the meter
• A second ground rod beside the meter
• Nothing; the meter body carries the current
• A bonding jumper around the meter

NEC Reference: NEC 250.53(D)(1)

Question 4: One raceway contains three branch circuits protected by 20 A, 30 A and 60 A breakers. A single copper equipment grounding conductor is used for all three. What size must it be?

• 14 AWG
• 12 AWG
• 10 AWG
• 8 AWG

NEC Reference: NEC 250.122(C)

Question 5: A motor branch circuit is protected by a 50 A inverse time circuit breaker. What is the minimum copper equipment grounding conductor for the motor circuit?

• 8 AWG
• 10 AWG
• 12 AWG
• 14 AWG

NEC Reference: NEC 250.122(D)(1)

Question 6: A dwelling has 9 kW of electric space heat and a 5 kW central air conditioner that never run at the same time. What load is used for heating and cooling in the service calculation?

• 5 kW
• 9 kW
• 11.5 kW
• 14 kW

NEC Reference: NEC 220.60

Question 7: A 240-volt, single-phase, 30 A load is fed with 10 AWG copper (10,380 cmil, K = 12.9). What is the maximum one-way circuit length that keeps voltage drop at 3% or less?

• 48 ft
• 72 ft
• 97 ft
• 193 ft

NEC Reference: NEC Chapter 9, Table 8

Question 8: A 5 kW electric heater runs 6 hours a day for 30 days. Electricity costs $0.15 per kWh. What is the energy cost?

• $22.50
• $45.00
• $135.00
• $270.00

Question 9: In a restaurant kitchen (other than a dwelling unit), which 125-volt, 20-ampere receptacles require GFCI protection?

• All of the kitchen receptacles of that rating
• Only those within 6 ft of a sink
• Only those serving countertop surfaces
• None; GFCI rules apply only to dwellings

NEC Reference: NEC 210.8(B)

Question 10: A detached one-family dwelling is supplied by a feeder from another building on the same property. What is the minimum rating of the dwelling's building disconnecting means?

• 200 A, 3-wire
• 100 A, 3-wire
• 60 A
• 30 A

NEC Reference: NEC 225.39(C)

Question 11: Where must a service head be located relative to the point of attachment of the service-drop conductors?

• At least 3 ft to one side of the attachment
• Below the point of attachment, to shed water
• Anywhere, as long as a drip loop is formed
• Above the attachment point (or within 24 in.)

NEC Reference: NEC 230.54(C)

Question 12: Equipment rated 800 A or more containing overcurrent devices has a personnel door within 25 ft of its working space. What does 110.26(C)(3) require for that door?

• It must open outward with listed panic hardware
• It must be at least 48 in. wide and 7 ft high
• It must be kept locked at all times when unattended
• It must have a vision panel so workers can be seen

NEC Reference: NEC 110.26(C)(3)

Question 13: Article 100 defines "weatherproof" as:

• Built so that water cannot enter under any condition
• Built so that dust cannot enter under any condition
• Suitable for continuous operation while submerged
• Built so weather exposure won't interfere with operation

NEC Reference: NEC Article 100

Question 14: A 20 µF capacitor and a 30 µF capacitor are connected in series. What is the total capacitance?

• 10 µF
• 12 µF
• 25 µF
• 50 µF

Question 15: A 200 ft feeder passes through a hot boiler room for 8 ft, where its ampacity is lower. May the higher ampacity of the rest of the run be used for the whole feeder?

• Yes; the low portion is under 10 ft and under 10% of length
• No, unless that part of the run is in PVC conduit
• Yes, but only if the conductors are aluminum
• No; the lowest ampacity always applies to the whole run

NEC Reference: NEC 310.14(A)(2)

Question 16: NM cable is run across the top of floor joists in an attic that is reached only by a scuttle hole. Within what distance of the scuttle hole must the cable be protected by guard strips?

• 10 ft
• 8 ft
• 6 ft
• 3 ft

NEC Reference: NEC 320.23(A) and 334.23

Question 17: What is the allowable ampacity of 18 AWG copper fixture wire?

• 3 A
• 6 A
• 8 A
• 10 A

NEC Reference: NEC Table 402.5

Question 18: May two circuit breakers be connected in parallel to protect a single set of conductors?

• Only if factory assembled and listed as a unit
• Yes, if each breaker is rated 100 A or more
• Yes, any two breakers of the same rating
• Never, under any circumstances at all

NEC Reference: NEC 240.8

Question 19: Where circuit breaker handles operate vertically, which handle position must be the "on" position?

• Either, if marked
• Down
• Whatever the manufacturer chooses
• Up

NEC Reference: NEC 240.81

Question 20: Motor feeder tap conductors are 20 ft long and terminate in a motor branch-circuit protective device. Their ampacity must be at least what fraction of the ampacity of the feeder conductors?

• 1/10
• 1/4
• 1/3
• 1/2

NEC Reference: NEC 430.28(2)

Question 21: Where may the disconnecting means for an air-conditioning condensing unit be mounted?

• On or in the unit, but not on access panels
• On a service-access panel of the unit itself
• Only at the panelboard serving the unit
• Only on the inside wall of the building

NEC Reference: NEC 440.14

Question 22: How must the lighting in an elevator car be supplied?

• From the elevator motor power circuit
• By a separate branch circuit for the car
• From a battery pack mounted on the car
• From a general lighting circuit in the hoistway

NEC Reference: NEC 620.22(A)

Question 23: The branch circuit supplying a fire alarm control unit must:

• Be a multiwire circuit shared with the exit sign circuits
• Be GFCI protected to protect the service technicians
• Have no GFCI/AFCI and a red FIRE ALARM CIRCUIT disconnect
• Be supplied from the nearest general lighting circuit

NEC Reference: NEC 760.41(B)

Question 24: Equipment for a Class I location is marked with temperature code T3. What is its maximum surface temperature?

• 135 °C
• 165 °C
• 200 °C
• 300 °C

NEC Reference: NEC 500.8(C)

Question 25: Open wiring conductors of intrinsically safe circuits must be separated from conductors of non-intrinsically safe circuits by at least:

• 6 in.
• 2 in.
• 1 in.
• 1/2 in.

NEC Reference: NEC 504.30(A)(2)

Question 26: A general-use dimmer switch may control which loads?

• Only motor loads rated up to 1/2 horsepower
• Any lighting load, including fluorescent ballasts
• Only receptacle outlets intended for table lamps
• Incandescent luminaires only, unless listed for others

NEC Reference: NEC 404.14(E)

Question 27: A receptacle in a location where the current Code requires GFCI protection is being replaced. What must the replacement be?

• An isolated ground receptacle
• Any grounding-type receptacle
• GFCI protected
• A weather-resistant receptacle only

NEC Reference: NEC 406.4(D)(3)

Question 28: When rigid metal conduit is joined, which practice is prohibited?

• Using running threads for connection at couplings
• Using threadless couplings on unthreaded conduit
• Using threaded couplings made up wrenchtight
• Using a three-piece union where needed

NEC Reference: NEC 344.42(B)

Question 29: A box is fastened to a stud with nails that pass through the interior of the box. How close to the back or ends of the box must the nails be?

• Within 1/2 in.
• Anywhere, if the nails are short
• Within 1/8 in.
• Within 1/4 in.

NEC Reference: NEC 314.23(B)(1)

Question 30: Which item must be on the nameplate of a 75 kVA dry-type transformer?

• The panelboard that feeds it
• The percent impedance
• The installer's name
• The date of the next inspection

NEC Reference: NEC 450.11(A)