National Electrical Installation Standards

Standards as High as Your Own

Wednesday, November 1, 2023


Thank you for providing this service & always looking forward to the next CQD. Why are the minimum bending requirements in Table 312.6(A) less than those found in Table 312.6(B)? Section 312.8(A)(1) states wiring space does not exceed 40% cross-sectional area, but (2) states splices, taps do not exceed 75% of the cross-sectional-area? If the maximum allowed wiring space is 40% why would 75% be allowed? Thank you, John.


Hello John, glad to hear you are enjoying the CQD. The two Tables in 312.6 cover two (2) different installation methods.

  • The space required in Table 312.6(A) is for installations where the conductors do not enter/leave the enclosure from the wall opposite to the terminals they are landed on.
  • The space required in Table 312.6(B) is for installations where the conductors do enter/leave the enclosure from the wall opposite to the terminals they are landed on. This could be an opening that is directly opposite the terminals, or and opening that is offset from the terminals, but still on the wall directly opposite of the terminals.

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