Skill room
Box Fill Room
Box fill is a counting exercise tied to Article 314.16. Each conductor, each clamp group, each support, each device yoke, and all grounds get counted, then multiplied by the volume for the largest conductor present. Miss the device count of two or the single ground count and the whole answer moves. Count clean and it holds.
Last reviewed June 2026 · Staff Answer
Daily drill · original
In a box-fill count, how many conductors does a single device yoke count as?
Pick an answer to see the work and why each wrong choice traps people.
What this room is for
- Counting conductors, clamps, supports, devices, and grounds correctly
- Using the largest conductor volume for the multipliers
- Catching the device-yoke count of two
What not to post
- Asking for quoted 314.16 text. Cite the article and table.
- Posting real exam questions.
- Sharing anything that identifies you.
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