Practice Test Geeks(E2) E2 Commercial Electrical Inspector Practice Test
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Systems and Equipment Flashcards

7 cards from real E2 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Systems and Equipment flashcards as text

  1. A commercial building's 277/480V lighting panelboard serves fluorescent fixtures with electronic ballasts. The inspector notes the neutral is undersized. Why is this a concern?

    Answer: Electronic ballasts generate 3rd-order harmonics that add on the neutral, potentially causing it to carry more current than the phase conductors

    Electronic ballasts and nonlinear loads produce triplen harmonics that accumulate on the neutral conductor, requiring it to be upsized per NEC 310.15(E).

  2. Under NEC Article 517, in a hospital's patient care area, the general care area (Category 1) requires that receptacles and fixed equipment be connected to which power system?

    Answer: Essential electrical system (EES) — equipment branch

    NEC 517.18 requires that patient bed locations in Category 1 (general care) spaces be served by the essential electrical system's equipment branch.

  3. During a commercial inspection, you observe that flexible metal conduit (FMC) is used for a 6-foot equipment connection at a motor. Under NEC 250.118(5), this FMC can serve as a grounding conductor only if it meets which condition?

    Answer: The FMC is listed and the circuit conductors are 10 AWG or smaller, and the FMC does not exceed 6 feet

    NEC 250.118(5) allows listed FMC to serve as a grounding conductor if conductors inside are 10 AWG or smaller and total length does not exceed 6 feet.

  4. A commercial building's 2000A service uses a ground fault protection (GFP) system. Per NEC 230.95, GFP is required when the service exceeds:

    Answer: 800A at 277/480V or higher grounded wye systems

    NEC 230.95 requires ground fault protection for solidly grounded wye services of more than 150 volts to ground but not exceeding 600V phase-to-phase, rated 800A or more.

  5. When inspecting a commercial occupancy's air-conditioning system with a hermetic refrigerant motor-compressor, the branch circuit overcurrent protection is permitted to be sized up to:

    Answer: 225% of the nameplate rated-load current

    NEC 440.22(A) allows the branch circuit overcurrent protection for a hermetic refrigerant motor-compressor to be sized up to 225% of the nameplate rated-load current.

  6. A commercial building's exit signs are required to be connected to which electrical system according to the NEC and NFPA 101?

    Answer: The emergency system, ensuring continuous illumination if normal power fails

    NEC 700.16 and NFPA 101 require exit signs to be connected to the emergency electrical system so they remain illuminated during a normal power failure.

  7. An inspector reviews a commercial building with a 600A, 120/208V panelboard. The calculated demand load is 480A. Under NEC 220.87, what method can be used to determine if additional load can be added without a full load calculation?

    Answer: Measure peak demand using a recording ammeter for 30 days

    NEC 220.87 allows the use of a 30-day peak demand recording to determine existing load, then apply 125% to verify if the service can support additional load.