Where an outlet box contains a receptacle and four 12-2 NM cables with no cable clamps, what is the minimum cubic inch capacity required for the box?

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Multiple Choice

Where an outlet box contains a receptacle and four 12-2 NM cables with no cable clamps, what is the minimum cubic inch capacity required for the box?

Explanation:
Box fill is about how much space the conductors and devices in a box take up, per NEC 314.16. Each insulated conductor that enters the box and is terminated or spliced inside counts as one fill unit. A group of equipment grounding conductors is treated as a single fill unit, using the largest grounding conductor size present. The device itself also adds fill: a single receptacle in a box counts as two conductor fills. Internal clamps would add another fill unit if present, but there are none here. In this scenario, four 12-2 NM cables bring in eight insulated conductors (hot and neutral from each cable). The four grounding conductors count as one fill unit. The receptacle adds two more fill units. No clamps are present. Total conductor equivalents: 8 + 1 + 2 = 11. For 12 AWG conductors, each fill unit requires 2.25 cubic inches. So 11 × 2.25 = 24.75 cubic inches. Therefore, the minimum box capacity needed is 24.75 cubic inches.

Box fill is about how much space the conductors and devices in a box take up, per NEC 314.16. Each insulated conductor that enters the box and is terminated or spliced inside counts as one fill unit. A group of equipment grounding conductors is treated as a single fill unit, using the largest grounding conductor size present. The device itself also adds fill: a single receptacle in a box counts as two conductor fills. Internal clamps would add another fill unit if present, but there are none here.

In this scenario, four 12-2 NM cables bring in eight insulated conductors (hot and neutral from each cable). The four grounding conductors count as one fill unit. The receptacle adds two more fill units. No clamps are present.

Total conductor equivalents: 8 + 1 + 2 = 11. For 12 AWG conductors, each fill unit requires 2.25 cubic inches. So 11 × 2.25 = 24.75 cubic inches.

Therefore, the minimum box capacity needed is 24.75 cubic inches.

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