NEC Table 310.16
What it means on the job
Per NEC Table 310.16, 10 AWG copper with 60°C insulation (NM-B) is rated for 30 amperes. A 30A dryer circuit using 10/3 NM-B cable (two hots, one neutral, one ground) is standard and code-compliant. The 40-foot run is well within voltage drop guidelines (typically under 3% for branch circuits).
Tested in 1 CraftIQ puzzle
- code-checkWire Sizing for 30A Circuit
Related NEC sections
NEC Chapter 9 Table 1 & Annex C Table C.1 / Article 358.22
1/2" EMT has only 0.122 sq in of usable area at 40% fill (Chapter 9, Table 4). Each #12 THHN is 0.0133 sq in (Chapter 9, Table 5), so ten conductors require 0.133 sq in — over the 40% limit. NEC Annex C, Table C.1 permits a maximum of 9 #12 THHN in 1/2" EMT.
NEC Chapter 9, Table 1 / Table 5
For three or more conductors, conduit fill is limited to 40% of the conduit's internal cross-sectional area per NEC Chapter 9, Table 1. Five #12 THHN conductors at 0.0133 sq in each = 0.0665 sq in total. The 40% fill for 1/2" EMT is 0.122 sq in. Since 0.0665 < 0.122, this is compliant. The two 90-degree bends total 180 degrees, which is under the 360-degree maximum per NEC 358.26 (EMT bends).
NEC Table 300.5
Direct-buried UF cable for a 120V, 20A GFCI-protected circuit requires a minimum burial depth of 12 inches. Without GFCI protection, the minimum is 24 inches. 6 inches is insufficient.
CraftIQ explanations are original educational commentary written in trade language and verified against the cited standards. Always confirm requirements against the code edition adopted by your jurisdiction — this is training material, not a substitute for the code book or your AHJ.