Practice Test Geeks(CEI) Certified Electrical Inspector Practice Test
← All CEI Flashcard Decks

Commercial & Industrial Systems Flashcards

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

Read the first 7 Commercial & Industrial Systems flashcards as text

  1. Per NEC 450.13, where must the secondary windings of a dry-type transformer rated over 600V be accessible to qualified persons?

    Answer: In any location accessible to qualified persons

    NEC 450.13(B) permits dry-type transformers over 600V to be installed in locations accessible to qualified persons without requiring a vault.

  2. What is the maximum voltage drop recommended by NEC 210.19(A) informational notes for branch circuits in commercial buildings?

    Answer: 3%

    NEC 210.19(A) Informational Note No. 4 recommends a maximum 3% voltage drop on branch circuits, with a total of 5% for feeders and branch circuits combined.

  3. In a commercial facility, which type of luminaire is required in a clothes closet per NEC 410.16?

    Answer: Totally enclosed luminaire or LED surface-mounted type

    NEC 410.16(A) permits only surface-mounted or recessed incandescent luminaires with completely enclosed lamps, or LED luminaires that are surface-mounted, in clothes closets.

  4. A 480V, 3-phase industrial feeder is protected by a 400A circuit breaker. The feeder supplies only motor loads. What is the minimum conductor ampacity required for the feeder per NEC 430.24?

    Answer: 125% of the largest motor FLC plus 100% of remaining motor FLCs

    NEC 430.24 requires feeder conductors for several motors to have an ampacity of at least 125% of the highest-rated motor's FLC plus 100% of all other motor FLCs.

  5. What NEC section governs the installation of emergency systems in commercial buildings, including lighting and power required for safety of human life?

    Answer: Article 700

    NEC Article 700 covers emergency systems—those legally required and classed as essential for safety of human life—including emergency lighting and emergency power.

  6. In a commercial building switchboard, what does NEC 408.3(F) require regarding the identification of each circuit?

    Answer: A legible directory must be posted at the switchboard identifying each circuit

    NEC 408.4 (formerly 408.3(F)) requires a legible circuit directory to be provided at each panelboard and switchboard identifying the load served by each circuit.

  7. A commercial building's service entrance uses 250 kcmil THWN-2 copper conductors in RMC. At what temperature rating must the terminations be evaluated when calculating allowable ampacity?

    Answer: 75°C

    Per NEC 110.14(C), unless the equipment is listed and marked for higher temperatures, conductor ampacity must be based on the 75°C column when terminating at equipment rated 75°C.