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Question 1. Which NEC article defines the term “grounded conductor”? A) Article 100 B) Article 250 C) Article 210 D) Article 430 Answer: A Explanation: Article 100 contains definitions for all NEC terms, including “grounded conductor”. Question 2. In a sign circuit, the minimum ampacity of a feeder supplying a 120 V LED sign rated at 1.5 A must be at least: A) 15 A B) 20 A C) 10 A D) 5 A Answer: A Explanation: NEC 210.20(A) requires feeder ampacity to be at least 125 % of the continuous load; 1.5 A × 1.25 = 1.875 A, and the smallest standard breaker is 15 A. Question 3. Which of the following wiring methods is permitted inside a sign enclosure that is rated for wet locations? A) NM cable B) MC cable with aluminum conductors C) Rigid metal conduit (RMC) D) Flexible metal conduit (FMC) without a grounding conductor Answer: C Explanation: RMC is listed for wet locations and provides a grounding path; NM is not permitted in wet locations. Question 4. The maximum voltage drop allowed for a sign circuit over a 100‑ft run, per NEC recommendations, is:
A) 2 %
B) 3 %
C) 5 %
D) 10 %
Answer: B Explanation: NEC recommends a maximum of 3 % voltage drop for branch circuits to maintain efficiency. Question 5. A neon sign operates at 15 kV. The secondary conductors feeding the tubes must be insulated for at least: A) 600 V B) 2 kV C) 5 kV D) 15 kV Answer: D Explanation: Conductors must be rated for the maximum system voltage; therefore, 15 kV insulation is required. Question 6. Under Texas Electrical Safety and Licensing Act, a Master Sign Electrician may: A) Perform all electrical work without a permit. B) Supervise Journeyman Sign Electricians on sign installations. C) Install only low‑voltage signage. D) Issue permits to other contractors. Answer: B Explanation: A Master Sign Electrician is authorized to supervise Journeymen on sign work but cannot issue permits. Question 7. The required disconnecting means for a sign must be located: A) Inside the sign enclosure only. B) Within sight of the sign and not more than 50 ft away.
D) 150 V AC or DC Answer: A Explanation: NEC defines Class 2 circuits as limited to 30 V AC or DC. Question 11. Which NEC article governs the installation of transformers used for neon sign power supplies? A) Article 430 B) Article 440 C) Article 450 D) Article 500 Answer: C Explanation: Article 450 covers transformers and transformer vaults, including those for signage. Question 12. For a sign located in a Class I, Division 2 hazardous area, the wiring method must be: A) NM cable in conduit. B) Rigid metal conduit with conductors rated for the area. C) Flexible metal conduit without a grounding conductor. D) Any wiring method as long as the equipment is listed. Answer: B Explanation: Hazardous locations require wiring methods specifically approved for the classification; RMC with appropriate conductors meets the requirement. Question 13. The NEC permits the use of “low‑voltage” (≤ 30 V) wiring for LED sign drivers without a separate grounding conductor because: A) The voltage is too low to cause shock. B) The conductors are automatically grounded. C) The driver is listed as a Class 2 power source. D) No grounding is ever required for LED signs. Answer: C
Explanation: Class 2 power sources are limited in voltage and current, reducing shock hazard, so a separate EGC is not required if the device is listed. Question 14. In Texas, the most recent NEC edition adopted for licensing examinations is: A) 2017 B) 2020 C) 2023 D) 2026 Answer: C Explanation: Texas has adopted the 2023 NEC edition for its licensing exams. Question 15. When installing a sign on a roof, the required fall protection must be provided when the work height exceeds: A) 4 ft B) 6 ft C) 10 ft D) 15 ft Answer: B Explanation: OSHA requires fall protection for work above 6 ft in the construction industry. Question 16. A sign’s branch circuit is protected by a 15 A breaker. The sign’s nameplate rating is 12 A continuous. Is this acceptable? A) Yes, because the breaker rating exceeds the load. B) No, because continuous loads must be limited to 80 % of breaker rating. C) Yes, if the breaker is a slow‑acting type. D) No, because the breaker must be at least 20 A. Answer: B Explanation: NEC 210.20(A) requires continuous loads to be limited to 80 % of the breaker rating; 12 A ÷ 15 A = 80 %, which is the maximum allowed, so it is acceptable. (Note: This is a borderline case; the answer is Yes, but the reasoning is that it meets the 80 % rule.)
A) Painted with any exterior paint. B) Listed for “wet locations.” C) Installed with a drainage sump. D) Covered with a tarp during rain. Answer: B Explanation: Enclosures in wet locations must be listed for wet conditions per NEC 600.11. Question 21. For a sign using a 24 V DC LED driver, the maximum allowable voltage drop on the feeder (2 % recommended) over a 150‑ft run carrying 8 A is: A) 0.48 V B) 1.92 V C) 3.84 V D) 4.80 V Answer: B Explanation: 2 % of 24 V = 0.48 V. However, the NEC recommendation applies to the system voltage, not the feeder voltage; the correct answer is 0.48 V. (Correction: The correct calculation is 2 % of 24 V = 0.48 V, so answer A.) Question 22. Which OSHA standard addresses lockout/tagout procedures for electrical work on signs? A) 1910. B) 1926. C) 1910. D) 1926. Answer: A Explanation: OSHA 1910.147 covers the control of hazardous energy (lockout/tagout). Question 23. A sign’s outline lighting system uses a 120 V, 60 Hz supply. The required disconnecting means must be rated at least: A) 120 V, 15 A
B) 125 V, 20 A
C) 120 V, 30 A
D) 250 V, 15 A
Answer: A Explanation: The disconnect must be rated for the circuit voltage and not less than the overcurrent protective device; a 15 A, 120 V breaker meets the requirement. Question 24. When installing a sign in a corrosive environment (e.g., near a chemical plant), the conduit material of choice is: A) EMT B) PVC conduit C) Rigid metal conduit (RMC) with a corrosion‑resistant coating D) Flexible metal conduit (FMC) Answer: C Explanation: RMC with a corrosion‑resistant coating provides the durability needed for harsh environments. Question 25. The NEC permits the use of “metal‑clad (MC) cable” for sign wiring only when: A) The cable is installed in a raceway. B) The cable is listed for outdoor use. C) The cable is under 30 A. D) The cable is used for low‑voltage (< 30 V) circuits. Answer: B Explanation: MC cable must be listed for the environment; outdoor‑rated MC can be used without a raceway. Question 26. A sign’s power supply is listed for “UL 1449” surge protection. This indicates compliance with standards for: A) Over‑current protection. B) Ground fault circuit interrupters.
Explanation: 5 kW at 250 V = 20 A. Per Table 310.15(B)(16), 6 AWG copper is required for 55 A, which comfortably exceeds 20 A with temperature correction. Question 30. Which of the following is a requirement for a sign’s “service disconnect” per NEC 600.6? A) Must be a fusible switch. B) Must be located within 10 ft of the sign. C) Must be capable of being locked in the open position. D) Must be a breaker with a minimum rating of 125 % of the sign’s load. Answer: D Explanation: The disconnect must be rated for at least 125 % of the sign’s load to accommodate continuous operation. Question 31. A sign’s wiring must be protected from physical damage. Which conduit type provides the highest protection? A) EMT B) RMC C) PVC conduit D) Flexible metal conduit Answer: B Explanation: RMC (Rigid Metal Conduit) offers the greatest mechanical protection among listed conduit types. Question 32. Which NEC article addresses “temporary wiring” that might be used during sign installation? A) Article 590 B) Article 410 C) Article 300 D) Article 500 Answer: A Explanation: Article 590 governs temporary wiring installations.
Question 33. For a sign that uses a Class 3 circuit, the maximum allowable voltage is: A) 30 V AC or DC B) 60 V DC only C) 100 V AC only D) 150 V AC or DC Answer: B Explanation: Class 3 circuits are limited to 60 V DC. Question 34. The NEC requires that a sign’s wiring be installed in a manner that allows easy access for inspection. This is achieved by: A) Embedding wires in concrete. B) Using conduit with removable fittings. C) Installing wires behind drywall. D) Covering wires with paint. Answer: B Explanation: Removable conduit fittings provide access for inspection and maintenance. Question 35. Which of the following is a permissible grounding method for a sign mounted on a steel pole? A) Using the pole as the sole grounding electrode. B) Connecting a grounding wire to the pole’s structural steel and bonding to the grounding electrode system. C) Relying on the sign’s internal ground strap only. D) No grounding required if the sign is low‑voltage. Answer: B Explanation: The pole must be bonded to the grounding electrode system to provide an effective ground. Question 36. A sign’s LED driver is listed for “IP65” protection. This rating indicates:
C) Signs that require a new electrical service. D) Temporary signs used for events. Answer: C Explanation: A permit is required when a new electrical service or alteration to existing service is involved. Question 40. Which NEC article governs the installation of “motor‑driven rotating signs”? A) Article 430 B) Article 440 C) Article 460 D) Article 600 Answer: A Explanation: Article 430 covers motors and motor‑controlled equipment, including rotating sign mechanisms. Question 41. The minimum size of a conduit fill for three 12 AWG THHN conductors in EMT is: A) 40 % B) 31 % C) 53 % D) 60 % Answer: B Explanation: For three conductors, the maximum conduit fill is 40 % of the conduit’s cross‑sectional area; however, the NEC tables specify 31 % for three conductors in EMT to stay within the limit. Question 42. A sign’s power supply is required to have a “listing” from which organization to be considered compliant? A) ISO B) UL C) ANSI D) IEEE
Answer: B Explanation: UL (Underwriters Laboratories) listing is required for most electrical equipment per NEC. Question 43. For a sign installed on a building’s roof, the required fire‑rating for the conduit passing through a fire‑rated wall is: A) Same rating as the wall. B) No rating needed if the conduit is metal. C) Must be a listed fire‑stop fitting. D) Must be PVC conduit. Answer: C Explanation: Fire‑stop fittings are required to maintain the fire‑rating of the wall when penetrated by conduit. Question 44. Which of the following is NOT a permissible “low‑voltage” wiring method for LED signs? A) MC cable listed for low‑voltage. B) NM cable in a conduit. C) Direct‑buried UF cable. D) Flexible metal conduit with THHN conductors. Answer: C Explanation: UF cable is not permitted for low‑voltage sign wiring unless specifically listed; the other methods are acceptable. Question 45. The NEC defines “service equipment” as: A) Any device that disconnects power to a single circuit. B) The means of delivering electricity from the utility to the building. C) Only the main breaker panel. D) The transformer only. Answer: B
Question 49. In a sign’s wiring diagram, the symbol “Δ” typically represents: A) A three‑phase delta connection. B) A changeover switch. C) A diode. D) A grounding electrode. Answer: A Explanation: The delta (Δ) symbol denotes a three‑phase delta configuration. Question 50. When a sign’s power supply is installed in a “wet location,” the enclosure must be listed for at least which NEMA rating? A) NEMA 1 B) NEMA 3R C) NEMA 4X D) NEMA 6 Answer: C Explanation: NEMA 4X provides protection against water, corrosion, and dust, suitable for wet locations. Question 51. Which of the following is a correct method for bonding a metal sign enclosure to the grounding system? A) Using a non‑conductive strap. B) Connecting a grounding lug to the enclosure and the grounding electrode system. C) Painting the enclosure with conductive paint. D) Relying on the conduit to provide bonding. Answer: B Explanation: A grounding lug or bonding jumper must be used to connect the metal enclosure to the grounding system.
Question 52. The NEC requires that a sign’s “service disconnect” be capable of being opened remotely. This is true for: A) All signs. B) Only signs with a voltage above 600 V. C) Only signs that are not readily accessible. D) No sign; remote operation is not required. Answer: D Explanation: NEC does not require remote operation of the service disconnect for signs. Question 53. A sign’s power supply is rated for 120/240 V, 3‑phase. The NEC allows a single‑phase connection only if: A) The sign is less than 500 W. B) The manufacturer permits single‑phase operation. C) The supply voltage is reduced to 120 V. D) The sign uses a transformer. Answer: B Explanation: The manufacturer’s listing determines whether a three‑phase device can be operated on single‑phase power. Question 54. Which NEC article deals with “equipment grounding conductors” for flexible cords? A) Article 400 B) Article 250 C) Article 210 D) Article 300 Answer: A Explanation: Article 400 covers flexible cords and cables, including grounding requirements. Question 55. For a sign that uses a “cold‑cathode” neon tube, the required clearance from combustible material is at least:
B) NM cable stapled directly to the face of a concrete wall. C) THHN conductors in EMT. D) MC cable in a metal raceway. Answer: B Explanation: Exposed NM cable stapled to a concrete surface is subject to physical damage and is not permitted. Question 59. Which NEC article provides the rules for “metallic raceways” used in sign installations? A) Article 300 B) Article 358 C) Article 376 D) Article 380 Answer: B Explanation: Article 358 covers Electrical Metallic Tubing (EMT), a common metallic raceway. Question 60. The NEC requires that a sign’s “disconnecting means” be capable of being locked in the open position. This is necessary to: A) Prevent unauthorized operation. B) Ensure the sign can be removed quickly. C) Provide a means for maintenance safety. D) All of the above. Answer: C Explanation: Lockable disconnects ensure safety during maintenance by preventing accidental re‑energization. Question 61. When calculating the ampacity of conductors for a sign’s feeder, which correction factor must be applied if the ambient temperature is 40 °C (104 °F) and the conductor is rated for 75 °C? A) 0. B) 0.
C) 0.
D) No correction needed. Answer: C Explanation: Table 310.15(B)(2)(a) provides a temperature correction factor of 0.94 for 40 °C at 75 °C rating. Question 62. A sign’s power supply is installed in a “dry location” but the enclosure is painted with a conductive metallic paint. This is: A) Acceptable if the paint is grounded. B) Not acceptable because the paint creates a shock hazard. C) Acceptable if the enclosure is listed for dry locations. D) Not acceptable because conductive paint is prohibited. Answer: C Explanation: As long as the enclosure is listed for the location, the paint does not affect compliance. Question 63. Which of the following is a required label on a sign’s disconnecting switch? A) Manufacturer’s name only. B) Voltage and amperage rating. C) Date of installation. D) Color of the sign. Answer: B Explanation: NEC 600.6 requires the disconnect to be labeled with its voltage and ampere rating. Question 64. For a sign that uses a 24 V DC driver, the maximum length of the flexible cord without a voltage drop exceeding 3 % is approximately: A) 50 ft B) 100 ft C) 150 ft D) 200 ft Answer: B
