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Journeyman Electrician Ultimate Exam
Question 1. Which equation correctly represents Ohm’s Law? A) V = I × R B) I = V × R C) R = V ÷ I D) V = I ÷ R Answer: A Explanation: Ohm’s Law states voltage (V) equals current (I) multiplied by resistance (R). Question 2. In a series circuit, the total resistance is: A) The sum of individual resistances B) The reciprocal of the sum of reciprocals C) Equal to the largest resistor only D) Independent of the number of resistors Answer: A Explanation: Series resistances add directly: R_total = R1 + R2 + …. Question 3. Which of the following describes a parallel circuit’s total current? A) It equals the current through any one branch B) It is the sum of the branch currents C) It is the product of branch currents D) It is the same as the source voltage Answer: B Explanation: In parallel, total current is the algebraic sum of the currents in each branch. Question 4. The magnetic field around a straight conductor is produced by: A) Voltage only B) Current flow C) Resistance alone
Journeyman Electrician Ultimate Exam
D) Insulation type Answer: B Explanation: A moving charge (current) creates a magnetic field encircling the conductor. Question 5. Which waveform is characteristic of AC power used in residential wiring? A) Sine wave B) Square wave C) Sawtooth wave D) Triangle wave Answer: A Explanation: Standard AC utility power is a sinusoidal waveform. Question 6. NEC Article 100 defines “grounded conductor” as: A) The conductor that carries current back to the source B) The conductor intentionally connected to earth C) The conductor that provides a fault path D) The conductor that carries no voltage under normal conditions Answer: D Explanation: A grounded (neutral) conductor is at zero voltage relative to earth in normal operation. Question 7. According to NEC Article 110, the working space in front of a panelboard must be at least: A) 24 inches wide and 30 inches deep B) 30 inches wide and 36 inches deep C) 30 inches wide and 30 inches deep D) 36 inches wide and 48 inches deep Answer: B
Journeyman Electrician Ultimate Exam
Question 11. The primary factor in determining load calculation for a dwelling unit is: A) Number of light fixtures B) Square footage of the living area C) Number of appliances D) Number of occupants Answer: B Explanation: NEC Article 220 uses floor area to compute general lighting and receptacle loads. Question 12. The ampacity of a copper conductor rated 75 °C in Table 310.16 is 65 A. If the ambient temperature is 40 °C, the corrected ampacity is: A) 65 A B) 70 A C) 60 A D) 55 A Answer: B Explanation: At 40 °C, a 10 % temperature correction factor applies, raising ampacity to 65 A × 1.10 ≈ 71 A (rounded to next standard size, 70 A). Question 13. THHN insulation is suitable for: A) Wet locations only B) Dry and damp locations up to 90 °C C) Direct burial without conduit D) High-temperature oven use only Answer: B Explanation: THHN is rated for 90 °C in dry locations and 75 °C in wet locations when used in conduit. Question 14. Compared to copper, aluminum conductors have: A) Higher conductivity per cross-section
Journeyman Electrician Ultimate Exam
B) Lower resistance and higher ampacity C) Lower conductivity, requiring larger size for same ampacity D) Identical mechanical strength Answer: C Explanation: Aluminum’s conductivity is about 61 % of copper, so larger cross-section is needed for equal ampacity. Question 15. EMT (Electrical Metallic Tubing) must be supported within how many feet of a box or fitting? A) 3 ft B) 6 ft C) 8 ft D) 10 ft Answer: B Explanation: NEC 358.30 requires EMT to be supported within 6 ft of each outlet, junction, or device. Question 16. The maximum conduit fill for a single 1-in. schedule 40 PVC conduit using three #4 AWG THHN conductors is: A) 53 % B) 40 % C) 31 % D) 25 % Answer: B Explanation: For more than two conductors, the fill limit is 40 % of the conduit’s internal cross-sectional area. Question 17. A pull box must be sized to accommodate a minimum volume of: A) 1 in³ per conductor entering the box B) 2 in³ per conductor entering the box C) 3 in³ per conductor entering the box
Journeyman Electrician Ultimate Exam
Question 21. The maximum number of services allowed at a single dwelling unit is: A) One B) Two C) Three D) Four Answer: A Explanation: NEC 230.71 permits only one service per dwelling unit. Question 22. For a 200-A residential service, the minimum size of the service-entrance conductor (copper) is: A) 2/0 AWG B) 3/0 AWG C) 4/0 AWG D) 1/0 AWG Answer: B Explanation: Table 310.15(B)(16) shows 3/0 AWG copper rated for 200 A at 75 °C. Question 23. The required bonding jumper between the service neutral and the grounding electrode conductor must be: A) No larger than the neutral conductor B) At least the size of the largest ungrounded conductor C) Sized per Table 250.122 based on overcurrent device rating D) Only a #12 AWG copper wire Answer: C Explanation: NEC 250.122 dictates grounding electrode conductor size according to the service overcurrent rating. Question 24. A GFCI receptacle must be installed in which of the following locations?
Journeyman Electrician Ultimate Exam
A) A finished basement dry wall B) A garage attached to a dwelling C) A kitchen countertop D) Both B and C Answer: D Explanation: GFCI protection is required in garages and kitchen countertop receptacles. Question 25. AFCI protection is mandated for: A) All 120-V branch circuits in dwelling bedrooms B) Only outdoor circuits C) All 240-V circuits in commercial buildings D) None of the above Answer: A Explanation: NEC 210.12 requires AFCI protection for bedroom branch circuits in dwellings. Question 26. The recommended maximum voltage drop for feeder circuits supplying sensitive equipment is: A) 1 % B) 2 % C) 3 % D) 5 % Answer: B Explanation: NEC recommends a maximum of 2 % voltage drop for feeders to sensitive loads. Question 27. A 30-A, 120-V branch circuit feeding a receptacle outlet must be protected by a breaker of at most: A) 30 A B) 35 A
Journeyman Electrician Ultimate Exam
Answer: B Explanation: Table 250.122 specifies #12 AWG copper for a 20-A overcurrent device. Question 31. Which method is permissible for bonding a metal conduit system to the grounding electrode conductor? A) Using a listed bonding jumper at each conduit end B) Relying on the conduit’s continuity without a jumper C) Installing a separate grounding rod for each conduit run D) None of the above Answer: B Explanation: Metal conduit, when installed per code, provides a grounding path and does not require additional jumpers. Question 32. A standard duplex receptacle in a dwelling must be rated for a minimum of: A) 15 A B) 20 A C) 30 A D) 40 A Answer: A Explanation: 15-amp receptacles are the minimum for general-purpose circuits in dwellings. Question 33. The correct term for a device that combines a switch and a receptacle in one enclosure is: A) Combo device B) Switch-receptacle C) Multi-function outlet D) Power strip Answer: B
Journeyman Electrician Ultimate Exam
Explanation: NEC refers to a “switch-receptacle” as a single device containing both functions. Question 34. A receptacle installed in a bathroom must be: A) GFCI protected and located within 3 ft of the basin B) AFCI protected only C) Rated 30 A D) Installed at least 6 ft above the floor Answer: A Explanation: NEC 210.8(A)(1) requires GFCI protection for bathroom receptacles. Question 35. For a motor rated 7 HP, 460 V, 3-phase, the full-load current (FLC) from Table 430.250 is approximately: A) 10 A B) 13 A C) 19 A D) 25 A Answer: C Explanation: Table 430.250 lists an FLC of about 19 A for a 7 HP, 460 V, 3-phase motor. Question 36. The required overload protection setting for the motor in Question 35, using a typical inverse-time relay, should be set to: A) 75 % of FLC B) 100 % of FLC C) 115 % of FLC D) 150 % of FLC Answer: C Explanation: NEC 430.32 permits overload devices set between 115 % and 125 % of the motor’s FLC.
Journeyman Electrician Ultimate Exam
A) #10 AWG
B) #8 AWG
C) #6 AWG
D) #4 AWG
Answer: B Explanation: Table 250.122 specifies #8 AWG copper for a 100-A service. Question 41. A photovoltaic (PV) array that supplies 5 kW at 48 V DC requires a maximum conductor size of: A) #12 AWG copper B) #10 AWG copper C) #8 AWG copper D) #6 AWG copper Answer: C Explanation: Using NEC 690.8(C)(2) and accounting for 3 % voltage drop, #8 AWG copper is appropriate for 48 V, 5 kW. Question 42. Emergency power systems must be capable of: A) Supplying 50 % of the normal load B) Supplying the entire normal load for at least 30 minutes C) Supplying only essential lighting D) Supplying a minimum of 10 kW at all times Answer: B Explanation: NEC 700.12 requires emergency systems to serve the entire essential load for a minimum of 30 minutes. Question 43. A power-limited circuit, as defined in NEC, is limited to a maximum of: A) 30 V and 100 VA B) 60 V and 150 VA
Journeyman Electrician Ultimate Exam
C) 100 V and 200 VA D) 120 V and 250 VA Answer: B Explanation: NEC 725.2 defines power-limited circuits as not exceeding 60 V and 150 VA. Question 44. The minimum clear working space for a ceiling-mounted fluorescent fixture is: A) 30 in. high, 30 in. wide, 48 in. deep B) 36 in. high, 30 in. wide, 36 in. deep C) 30 in. high, 24 in. wide, 30 in. deep D) 24 in. high, 30 in. wide, 30 in. deep Answer: A Explanation: NEC 110.26(A)(1) requires a minimum of 30 in. high, 30 in. wide, and 36 in. deep (48 in. for equipment over 6 ft high). For most fixtures, 30 × 30 × 48 in. is standard. Question 45. When installing a receptacle in a kitchen countertop, the receptacle must be: A) At least 12 in. above the countertop surface B) No more than 20 in. above the countertop surface C) Within 12 in. of the countertop edge D) No higher than 48 in. from the floor Answer: C Explanation: NEC 210.52(C)(1) requires countertop receptacles to be installed so that no point on the countertop is more than 24 in. from the receptacle; the typical mounting height is within 12 in. of the counter. Question 46. The permissible ampacity of a 4-wire, 3-phase, 75 °C copper conductor in a raceway with 4 current-carrying conductors is: A) 100 % of the table value B) 80 % of the table value
Journeyman Electrician Ultimate Exam
B) 8
C) 10
D) 12
Answer: B Explanation: NEC 210.52(A)(1) requires one receptacle for each wall space 2 ft wide; a 20-ft wall provides 10 receptacles, the 15-ft wall provides 7; the minimum of the two is 8. Question 50. A grounding electrode conductor (GEC) must be installed in raceway when: A) The GEC is longer than 10 ft B) The GEC is exposed to physical damage C) The GEC is copper larger than #4 AWG D) The GEC is installed outdoors Answer: B Explanation: NEC 250.64(A) requires the GEC to be protected from physical damage, often by raceway. Question 51. Which of the following is the correct definition of “continuous load” per NEC? A) A load that operates for more than 3 hours continuously B) A load that operates for 8 hours a day C) Any load that is not a motor D) A load that is switched on and off frequently Answer: A Explanation: NEC defines a continuous load as one expected to run for three hours or more. Question 52. The minimum size of a grounding electrode conductor for a 400 A service using aluminum conductors is: A) #2 AWG
Journeyman Electrician Ultimate Exam
B) #4 AWG
C) #6 AWG
D) #8 AWG
Answer: B Explanation: Table 250.122 indicates #4 AWG aluminum for a 400-A service. Question 53. For a 120-V, 20-A circuit feeding a receptacle, the required conduit fill for two #12 AWG THHN conductors plus a #10 AWG ground is: A) 31 % B) 40 % C) 53 % D) 60 % Answer: B Explanation: Two #12 AWG (≈0.013 in² each) plus #10 AWG ground (≈0.021 in²) totals 0.047 in², which is within 40 % of a 1/2-in. EMT conduit (≈0.122 in²). Question 54. The NEC permits the use of “flexible metal conduit” (FMC) for: A) Outdoor wet locations only B) Exposed interior installations with support every 3 ft C) Direct burial without conduit D) Underground raceway without protection Answer: B Explanation: FMC must be supported within 3 ft and is allowed for interior exposed work. Question 55. A “dedicated branch circuit” is required for which of the following appliances? A) Dishwasher B) Refrigerator C) Microwave oven
Journeyman Electrician Ultimate Exam
Explanation: NEC 220.12 requires 3 VA per square foot for general lighting; 2,500 ft² × 3 VA = 7,500 VA, divided by 180 VA per fixture ≈ 42 fixtures; rounded to nearest standard, 30–40. The closest answer is 30. Question 59. The NEC requires that a grounding electrode be installed within how many feet of the service entrance? A) 5 ft B) 10 ft C) 25 ft D) No specific distance, just must be connected Answer: D Explanation: NEC 250.50 does not prescribe a distance; the electrode must be accessible and properly bonded. Question 60. A 120/240-V, 30-A dryer requires a neutral conductor of what minimum size? A) #14 AWG copper B) #12 AWG copper C) #10 AWG copper D) #8 AWG copper Answer: B Explanation: The neutral must be sized for the same ampacity as the ungrounded conductors; #12 AWG copper is rated for 30 A. Question 61. Which of the following is the correct NEC definition of “equipment grounding conductor” (EGC)? A) The conductor that carries fault current back to the source B) The conductor that provides a low-impedance path to ground for fault currents C) The conductor that supplies power to equipment D) The conductor that is bonded to the neutral at the service Answer: B
Journeyman Electrician Ultimate Exam
Explanation: An EGC provides a low-impedance path for fault current to facilitate protective device operation. Question 62. The required size of a conduit for a single 500 kcmil aluminum feeder with three current-carrying conductors is: A) 2-in. B) 2-1/2-in. C) 3-in. D) 4-in. Answer: B Explanation: The cross-sectional area of three 500 kcmil Al conductors (~0.411 in² each) requires a conduit that can accommodate 40 % fill; 2-1/2-in. PVC (≈0.845 in²) meets this requirement. Question 63. The NEC allows the use of a “ground-fault circuit interrupter” (GFCI) in which of the following locations without additional protection? A) Outdoor receptacles B) Basement utility rooms C) Garages attached to dwellings D) All of the above Answer: D Explanation: GFCI protection is required in all listed locations per NEC 210.8(A). Question 64. For a motor-operated pump rated 2 HP, 230 V, the required minimum size of a disconnecting means is: A) 15 A B) 20 A C) 30 A D) 40 A Answer: C
