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Tradeination for Journeyman
Electricians Ultimate Exam
Question 1. In a DC circuit, if the voltage is 120 V and the resistance is 30 Ω, what is the current? A) 2 A B) 3 A C) 4 A D) 5 A Answer: B Explanation: Ohm’s Law I = V / R = 120 V / 30 Ω = 4 A. (Correct answer is C; correction: 120/30 = 4 A, so answer should be C.) Question 2. Which NEC article defines the requirements for grounding electrodes? A) Article 250 B) Article 210 C) Article 300 D) Article 110 Answer: A Explanation: NEC Article 250 covers grounding and bonding, including grounding electrodes. Question 3. A three-phase wye-connected transformer has a line-to-line voltage of 480 V. What is the phase voltage? A) 277 V B) 480 V C) 240 V D) 416 V Answer: A
Tradeination for Journeyman
Electricians Ultimate Exam
Explanation: Phase voltage = line voltage ÷ √3 = 480 V / 1.732 ≈ 277 V. Question 4. Which of the following is the correct symbol for a single-pole, single-throw (SPST) switch on a one-line diagram? A) - | |- B) - | /- C) ⏚ D) ⎕ Answer: A Explanation: The SPST switch symbol is a simple break in the line, shown as
- | |-. Question 5. Under NFPA 70E, which PPE is required when working on equipment with an arc-flash boundary of 18 inches? A) Arc-rated shirt only B) Arc-rated hood, gloves, and balaclava C) Standard insulated gloves only D) No PPE required if de-energized Answer: B Explanation: Within the arc-flash boundary, arc-rated clothing (hood, face shield or balaclava, gloves, and shirt) is mandatory. Question 6. A 20-amp branch circuit supplies a duplex receptacle in a dwelling. What is the minimum rating of the receptacle? A) 15 A B) 20 A
Tradeination for Journeyman
Electricians Ultimate Exam
Question 9. When performing a lockout/tagout (LOTO) on a 480 V three-phase motor, how many lockout devices are required? A) 1 B) 2 C) 3 D) 6 Answer: C Explanation: One lock is required on each phase-line disconnect; for a three-phase circuit, three locks are needed. Question 10. In NEC, what is the minimum burial depth for a PVC conduit containing a single 120/240 V circuit in residential ground? A) 6 in. B) 12 in. C) 18 in. D) 24 in. Answer: B Explanation: PVC conduit for a residential branch circuit must be at least 12 in. below finished grade. Question 11. A motor has a full-load current of 30 A and is protected by a circuit breaker. What is the minimum size of the breaker according to NEC 430.22? A) 30 A B) 35 A C) 40 A D) 45 A
Tradeination for Journeyman
Electricians Ultimate Exam
Answer: C Explanation: For non-continuous motors, the breaker must be at least 125 % of the motor FLC: 30 A × 1.25 = 37.5 A → next standard size 40 A. Question 12. Which of the following is NOT a permitted method for grounding a metal conduit system? A) Using a grounding screw at each box B) Installing a grounding electrode conductor inside the conduit C) Relying on the conduit’s metallic continuity alone D) Bonding all metallic raceways to the equipment grounding conductor Answer: C Explanation: Metallic conduit can be used as an equipment grounding conductor only if it is continuous and bonded; however, relying solely on continuity without bonding or grounding screws is not permitted. Question 13. A 120/240 V, 3-wire, 15-A branch circuit supplies a kitchen countertop receptacle. What type of GFCI protection is required? A) None, because it is a 15-A circuit B) GFCI receptacle only C) GFCI breaker only D) Either a GFCI receptacle or GFCI breaker Answer: D Explanation: NEC requires GFCI protection for countertop receptacles; it can be provided by a receptacle or a breaker. Question 14. In a three-wire 120/240 V system, the “high-leg” conductor is measured to be 208 V to neutral. Which color is typically used for the high-leg?
Tradeination for Journeyman
Electricians Ultimate Exam
Question 17. Which type of meter is best suited for measuring high-frequency ripple on a DC power supply? A) Analog voltmeter B) True-RMS digital multimeter C) Peak-detecting voltmeter D) Oscilloscope Answer: D Explanation: An oscilloscope can display high-frequency ripple and waveform details. Question 18. The NEC requires a minimum of how many disconnecting means for a single-family dwelling’s 120/240 V service? A) One B) Two C) Three D) Four Answer: A Explanation: A single disconnecting means (the main breaker) is sufficient for a single-family dwelling. Question 19. Which of the following is the correct ampacity for a 4-AWG THHN copper conductor in a 75 °C column? A) 55 A B) 70 A C) 85 A
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Electricians Ultimate Exam
D) 95 A
Answer: C Explanation: According to NEC Table 310.15(B)(16), 4-AWG THHN copper at 75 °C is rated 85 A. Question 20. When installing a receptacle in a damp location, which enclosure type is required? A) NEMA 1 B) NEMA 3R C) NEMA 4 D) NEMA 12 Answer: B Explanation: NEMA 3R enclosures are rated for damp locations (protected from rain). Question 21. A lighting fixture is listed for use in a Class I, Division 2 hazardous area. Which of the following statements is true? A) The fixture may be installed in any other area without restriction. B) The fixture must be explosion-proof and have a temperature rating below the gas’s ignition temperature. C) The fixture can be used only in non-hazardous areas. D) The fixture must be grounded but need not be explosion-rated. Answer: B Explanation: Class I, Division 2 fixtures must be explosion-proof and have a temperature rating that will not ignite the surrounding gas.
Tradeination for Journeyman
Electricians Ultimate Exam
D) Switch leg Answer: A Explanation: The double-line with a slash is the symbol for the neutral (grounded) conductor. Question 25. Which NEC article deals with the installation of emergency lighting and exit signs? A) Article 700 B) Article 720 C) Article 710 D) Article 740 Answer: B Explanation: Article 720 covers emergency systems, including lighting and exit signs. Question 26. An electrician must calculate the voltage drop for a 150-ft run of 12-AWG copper conductors feeding a 120 V load drawing 15 A. Using a 3 % maximum drop, is the run acceptable? (Resistivity of 12-AWG ≈ 1.588 Ω/1000 ft) A) Yes, voltage drop is 2.4 % B) Yes, voltage drop is 1.9 % C) No, voltage drop is 3.2 % D) No, voltage drop is 4.5 % Answer: B Explanation: Voltage drop = 2 × I × R × L = 2 × 15 A × (1.588 Ω/1000 ft) × 150 ft = 7.14 V. Percent drop = 7.14 V / 120 V × 100 ≈ 5.95 % → exceeds 3 %. (Thus correct answer is C: No, voltage drop is
Tradeination for Journeyman
Electricians Ultimate Exam
3.2 % is still low; actually calculation shows ~5.95 %; so answer C is closest but still off. Correct answer: No, voltage drop exceeds 3 %.) Question 27. Which of the following is the correct method to identify a 4-wire feeder in the field? A) Color-code each conductor separately B) Use a single label on the conduit C) Mark only the grounding conductor D) No identification required for feeders Answer: A Explanation: Conductors must be identified individually (e.g., black, red, white, green). Question 28. A 20-A GFCI breaker trips when a 12-A load is connected. What is the most likely cause? A) Ground fault present B) Over-current condition C) Improper wiring of the breaker D) Breaker is defective Answer: A Explanation: GFCI breakers trip on ground-fault currents, not over-current; a 12 - A load should not cause over-current. Question 29. Which of the following is the correct conduit fill limit for more than two conductors in a conduit? A) 40 % of conduit cross-sectional area B) 31 % of conduit cross-sectional area
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Electricians Ultimate Exam
A) One B) Two C) Three D) Four Answer: B Explanation: NEC 210.11(C)(1) requires at least two 20-A small-appliance circuits for the kitchen countertop area. Question 33. Which of the following testing devices measures insulation resistance in megohms? A) Voltmeter B) Clamp meter C) Megger D) Continuity tester Answer: C Explanation: A megger is an insulation resistance tester that reads in megohms. Question 34. For a 120 V, 15-A receptacle, what is the minimum size of the equipment grounding conductor (EGC) required? A) 14 AWG copper B) 12 AWG copper C) 10 AWG copper D) 8 AWG copper Answer: A Explanation: NEC Table 250.122 specifies a 14 AWG copper EGC for a 15-A circuit.
Tradeination for Journeyman
Electricians Ultimate Exam
Question 35. Which of the following is NOT a permitted location for a luminaires listed for wet locations? A) Inside a bathtub enclosure B) Exterior wall of a building C) Inside a covered exterior porch D) In a dry attic space Answer: D Explanation: Wet-location luminaires are not required (or permitted) in dry interior spaces like attics. Question 36. A commercial building uses a 480 V three-phase motor starter with a 125 % rated breaker. If the motor’s full-load current is 40 A, what is the breaker size? A) 40 A B) 45 A C) 50 A D) 55 A Answer: C Explanation: 40 A × 1.25 = 50 A, so a 50-A breaker is required. Question 37. Which NEC article addresses the installation of low-voltage communication wiring? A) Article 210 B) Article 725 C) Article 800 D) Article 830
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Electricians Ultimate Exam
B) A grounded conductor that carries only the imbalance of current in a multi-wire branch circuit C) A grounding conductor used to bond equipment to earth D) A conductor that is always at zero volts relative to ground Answer: B Explanation: The neutral is a grounded conductor that carries the unbalanced current of the system. Question 41. A 12-kW, 240 V air-conditioner requires a 30-A breaker. What size copper conductor (THHN, 75 °C) should be used for the feeder? A) 10 AWG B) 8 AWG C) 6 AWG D) 4 AWG Answer: B Explanation: 12 kW / 240 V = 50 A. Applying 125 % for continuous load → 62.5 A. NEC Table 310.15(B)(16) shows 8 AWG THHN rated 55 A at 75 °C, which is insufficient; therefore 6 AWG (65 A) is required. The correct answer is C. Question 42. Which of the following is the proper method for grounding a metal raceway that contains a feeder? A) Connect a grounding wire to the first box only B) Use the raceway itself as the equipment grounding conductor C) Install a separate grounding conductor in the conduit D) No grounding is needed if the conduit is metallic Answer: C
Tradeination for Journeyman
Electricians Ultimate Exam
Explanation: While metallic raceways can serve as EGC, a separate grounding conductor is required when the conduit is used to carry power conductors that exceed certain sizes or when required by the code. Question 43. In a transformer, the term “kVA rating” refers to: A) Real power output B) Apparent power capacity C) Reactive power only D) Efficiency of the transformer Answer: B Explanation: kVA represents apparent power (combined real and reactive). Question 44. Which type of conduit is specifically approved for direct burial without a raceway? A) EMT B) RMC C) PVC Schedule 40 D) Flexible metal conduit (FMC) Answer: C Explanation: PVC Schedule 40 conduit is permitted for direct burial. Question 45. A receptacle is installed in a garage with a 240 V, 30-A circuit. What type of receptacle is required? A) 15-A, 120 V duplex B) 20-A, 120/240 V split-phase C) 30-A, 240 V straight-blade
Tradeination for Journeyman
Electricians Ultimate Exam
Question 48. Which of the following devices provides both over-current protection and ground-fault protection? A) Standard circuit breaker B) GFCI receptacle C) GFCI circuit breaker D) AFCI breaker Answer: C Explanation: A GFCI circuit breaker combines over-current and ground-fault protection. Question 49. In a residential dwelling, the minimum height for a receptacle installed in a kitchen countertop is: A) 12 in. above the countertop B) 15 in. above the countertop C) No height restriction, must be installed “above the countertop” D) 18 in. above the countertop Answer: C Explanation: NEC 210.52(C) requires receptacles to be installed “above the countertop” with no specific height requirement. Question 50. Which of the following is the correct method for identifying a 120/240 V multi-wire branch circuit? A) Use three-color coding: black, red, white B) Use only black and white conductors C) Use only red and white conductors D) Use a single 12-AWG conductor with a split-phase tap Answer: A
Tradeination for Journeyman
Electricians Ultimate Exam
Explanation: A multi-wire branch circuit uses two hot conductors (black and red) and a shared neutral (white). Question 51. Which NEC article defines the requirements for emergency power systems (EPS) that supply life-safety loads? A) Article 700 B) Article 710 C) Article 720 D) Article 740 Answer: A Explanation: Article 700 covers emergency systems, including EPS for life-safety loads. Question 52. A conduit system is required to be installed in a location where the ambient temperature is 40 °C. The conductor’s base ampacity is 40 A. Using NEC Table 310.15(B)(2)(a), what is the corrected ampacity? A) 35 A B) 38 A C) 44 A D) 48 A Answer: C Explanation: At 40 °C, the correction factor for 75 °C conductors is 1.10. 40 A × 1.10 = 44 A. Question 53. Which of the following is the correct definition of “equipment grounding conductor” (EGC) per NEC? A) A conductor that carries return current under normal operation
