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Question 1. Which Rhode Island General Law section primarily governs the licensing of electrical contractors? A) RIGL § 5‑ 3 ‑ 1 B) RIGL § 24‑ 6 ‑ 1 C) RIGL § 21‑ 2 ‑ 2 D) RIGL § 13‑ 4 ‑ 5 Answer: B Explanation: RIGL § 24‑ 6 ‑1 establishes the requirements, renewal procedures, and scope of work for electrical contractors in Rhode Island. Question 2. Under the NEC, which article defines the term “qualified person”? A) Article 90 B) Article 100 C) Article 110 D) Article 210 Answer: B Explanation: Article 100 provides definitions for NEC terms, including “qualified person,” meaning someone with the skills and knowledge to perform specific tasks safely. Question 3. The Authority Having Jurisdiction (AHJ) in Rhode Island for most utility pole work is:
A) OSHA
B) Department of Labor and Training (DLT) C) Rhode Island Public Utilities Commission (RI PUC) D) Federal Energy Regulatory Commission (FERC) Answer: C Explanation: The RI PUC acts as the AHJ for utility distribution and transmission systems, enforcing compliance with codes and standards. Question 4. OSHA Subpart V of 29 CFR 1926 primarily addresses safety for: A) Confined spaces B) Electrical power transmission and distribution C) Fall protection D) Hazardous materials handling Answer: B Explanation: Subpart V covers safety and health regulations specific to power transmission and distribution activities. Question 5. According to OSHA, the minimum approach distance to an energized 13.8 kV line for an unqualified worker is: A) 10 ft B) 15 ft C) 20 ft
Question 8. The inductive reactance (X_L) of a conductor at 60 Hz with an inductance of 0.2 H is: A) 7.54 Ω B) 12.57 Ω C) 18.85 Ω D) 37.70 Ω Answer: B Explanation: X_L = 2πfL = 2π × 60 × 0.2 ≈ 12.57 Ω. Question 9. When calculating voltage drop, which factor is NOT considered? A) Conductor resistance B) Load current C) Ambient temperature D) Color of insulation Answer: D Explanation: Insulation color does not affect voltage drop; resistance, current, and temperature corrections are relevant. Question 10. A power factor of 0.85 lagging indicates: A) Predominantly capacitive load B) Predominantly inductive load
C) Unity power factor D) No reactive power Answer: B Explanation: Lagging power factor signifies inductive load, where current lags voltage. Question 11. To correct a lagging power factor of 0.85 to 0.95 on a 500 kW load, the required kVAR of capacitors is approximately: A) 70 kVAR B) 110 kVAR C) 150 kVAR D) 200 kVAR Answer: B Explanation: Required kVAR = kW × (tan cos⁻¹ 0.85 – tan cos⁻¹ 0.95) ≈ 500 × (0.619 – 0.328) ≈ 145 kVAR, rounded to the nearest standard size, 110 kVAR. Question 12. A three‑phase transformer rated at 250 kVA, 13.8 kV/480 V, can supply a maximum single‑phase load of: A) 70 kW B) 100 kW C) 125 kW D) 250 kW
Question 15. A dead‑end insulator is used when: A) The conductor is supported at both ends B) The conductor terminates at the pole and must be restrained C) The line is a taut‑string configuration D) The pole is made of steel Answer: B Explanation: Dead‑end insulators provide mechanical tension support for conductors terminating at a pole. Question 16. The primary purpose of guy wires on a utility pole is to: A) Increase electrical conductivity B) Reduce sag in the conductor C) Provide lateral stability against wind loads D) Support the transformer weight Answer: C Explanation: Guy wires counteract bending moments from wind and ice, stabilizing the pole. Question 17. For a span of 150 ft, an ACSR “Big‑Bend” conductor, and a temperature rise of 30 °C, the required tension to limit sag to 2 ft is approximately:
A) 1,200 lb B) 2,500 lb C) 4,800 lb D) 7,200 lb Answer: C Explanation: Sag‑tension calculations using standard ACSR tables yield a required tension near 4,800 lb for those conditions. Question 18. The minimum clearance between a 13.8 kV overhead line and a public road is: A) 8 ft B) 10 ft C) 12 ft D) 15 ft Answer: D Explanation: NEC Article 225 and state regulations typically require at least 15 ft clearance for 13.8 kV lines over public ways. Question 19. A single‑phase distribution transformer is installed on a pole with a bank of three units. This configuration is primarily used to: A) Provide redundancy for reliability B) Reduce voltage drop
Explanation: Lightning arresters provide a low‑impedance path to ground for lightning, protecting equipment. Question 22. Underground vaults must be ventilated to prevent the buildup of: A) Carbon monoxide B) Hydrogen sulfide C) Methane and other gases D) Radon Answer: C Explanation: Confined spaces like vaults can accumulate methane and other combustible gases, requiring ventilation. Question 23. In Rhode Island, “Dig Safe” notification must be given at least how many hours before excavation? A) 6 hours B) 12 hours C) 24 hours D) 48 hours Answer: C Explanation: State law requires a minimum 24‑hour notice to utility companies before digging.
Question 24. The NEC requires a grounding electrode system for a service disconnect. Which of the following is an acceptable electrode? A) Metal water pipe in contact with earth for at least 10 ft B) Any metal conduit run underground C) A single steel rod 4 ft deep D) A copper braid wrapped around the service mast Answer: A Explanation: A metal water pipe in direct contact with earth for 10 ft or more qualifies as a grounding electrode under NEC 250.52(A)(1). Question 25. Personal protective grounding (PPG) for a worker on an energized line is accomplished by: A) Wearing rubber gloves only B) Connecting a grounding strap to the line and the worker’s body C) Standing on a dry wooden platform D) Using a non‑conductive ladder Answer: B Explanation: PPG involves a low‑impedance path from the worker to ground, typically via a grounding strap, to keep the worker at line potential. Question 26. The NEC defines a “bonding jumper” as a: A) Conductor that carries fault current to ground
D) The line is de‑energized Answer: C Explanation: When a fault energizes the ground, voltage gradients (step potential) can cause dangerous currents through a person’s feet. Question 29. Which PPE is required for a worker performing hot‑stick work on a 15 kV line? A) Hard hat, safety glasses, leather gloves B) Arc‑rated face shield, insulated hot‑stick, dielectric boots C) Rubber gloves, safety vest, steel‑toe boots D) Hearing protection, safety harness, insulated ladder Answer: B Explanation: Hot‑stick work on energized lines requires arc‑rated face protection, an insulated hot‑stick, and dielectric footwear. Question 30. The minimum breaking capacity for a fuse used on a 13.8 kV distribution circuit is: A) 5 kA B) 10 kA C) 20 kA D) 40 kA Answer: C
Explanation: High‑voltage distribution circuits typically require fuses with a minimum breaking capacity of 20 kA to safely interrupt fault currents. Question 31. In a confined‑space rescue, the primary concern before entry is: A) Availability of a fire extinguisher B) Atmospheric testing for oxygen, CO, and H₂S levels C) Presence of a rescue ladder D) Weather conditions outside the space Answer: B Explanation: Confined‑space entry must be preceded by atmospheric testing to ensure safe oxygen levels and absence of toxic gases. Question 32. The NEC permits a clearance of 3 ft between a 277 V overhead conductor and a residential roof. This clearance is considered: A) Minimum for all voltages B) Permissive, not mandatory C) Mandatory for 277 V only D) Not allowed; must be 5 ft Answer: B Explanation: NEC Article 225 provides permissible clearances; they are not mandatory unless specified by local ordinances.
B) Is the final pole at the end of a line segment C) Has a transformer mounted on it D) Is made of concrete Answer: B Explanation: A dead‑end pole terminates a line segment and must support the full mechanical tension of the conductors. Question 36. The primary function of a “stress cone” on a medium‑voltage cable termination is to: A) Provide a waterproof seal B) Reduce electric field stress at the cable end C) Serve as a grounding point D) Allow for cable flexibility Answer: B Explanation: Stress cones distribute the electric field, preventing dielectric breakdown at the termination. Question 37. When performing a VLF (Very Low Frequency) test on a cable, the test voltage is typically: A) 1 kV B) 5 kV C) 10 kV
D) 30 kV Answer: B Explanation: VLF testing commonly uses a 5 kV test voltage to verify insulation integrity without the high stresses of full‑power testing. Question 38. According to NEC Article 300.5, the minimum cover depth for a 4 ‑in. PVC conduit in residential soil is: A) 12 in. B) 18 in. C) 24 in. D) 30 in. Answer: B Explanation: NEC Table 300.5 specifies a minimum of 18 in. cover for 4‑in. PVC conduit in residential applications. Question 39. A “live‑line” work permit is required when: A) The line is de‑energized but not grounded B) The line is energized and workers will be in proximity C) The line is under maintenance but not in service D) The line is being installed for the first time Answer: B
Question 42. The recommended minimum distance between a 25 kV line and a residential building is: A) 15 ft B) 20 ft C) 30 ft D) 45 ft Answer: D Explanation: NEC Article 225.15 requires a minimum of 45 ft clearance for 25 kV lines from residential structures. Question 43. When using a bucket truck for pole climbing, the maximum allowable load on the bucket for a single worker is: A) 150 lb B) 250 lb C) 300 lb D) 400 lb Answer: C Explanation: OSHA 1926.550(b)(1) limits bucket load to 300 lb for a single occupant to ensure safe operation. Question 44. A “recloser” is typically set to reclose after how many seconds following a fault? A) 0.5 s
B) 2 s C) 5 s D) 10 s Answer: B Explanation: Most reclosers are programmed for a 2‑second interval before attempting to reclose. Question 45. The NEC requires that all grounding electrode conductors be: A) Copper only B) No smaller than 6 AWG copper or 4 AWG aluminum C) Bare copper only D) Insulated with PVC Answer: B Explanation: NEC 250.66 specifies minimum sizes for grounding electrode conductors: 6 AWG copper or 4 AWG aluminum for typical services. Question 46. In a three‑phase wye system, the line‑to‑neutral voltage is: A) Equal to the line‑to‑line voltage B) √3 times the line‑to‑line voltage C) 1/√3 times the line‑to‑line voltage D) Half the line‑to‑line voltage Answer: C
