In 1/2 inch EMT, what is the maximum number of 14 AWG, RHH conductors allowed?

In 1/2 inch EMT, what is the maximum number of 14 AWG, RHH conductors allowed?

• A. 6
• B. 7
• C. 4
• D. 3

Answer: (C)

Conduit fill is the main idea here. NEC limits how much cross-sectional area of conductors can be inside a raceway, so the total area of all insulated conductors may not exceed a certain percentage of the interior cross-sectional area of the conduit (roughly 40% for dry locations). A 1/2 inch EMT has a fixed interior area, and when you include the insulation thickness of 14 AWG RHH conductors, the space each conductor takes up is fairly substantial. With those dimensions, the group of conductors can reach the fill limit after about four wires. So four 14 AWG RHH conductors is the maximum that fits without violating the fill rule.

Conduit fill is the main idea here. NEC limits how much cross-sectional area of conductors can be inside a raceway, so the total area of all insulated conductors may not exceed a certain percentage of the interior cross-sectional area of the conduit (roughly 40% for dry locations). A 1/2 inch EMT has a fixed interior area, and when you include the insulation thickness of 14 AWG RHH conductors, the space each conductor takes up is fairly substantial. With those dimensions, the group of conductors can reach the fill limit after about four wires. So four 14 AWG RHH conductors is the maximum that fits without violating the fill rule.