How Many 6 AWG Wires Fit in PVC Conduit?

Complete NEC-compliant fill chart for 6 AWG THHN wires in Schedule 40 PVC (PVC) conduit. Maximum wire counts for all standard conduit sizes.

Quick Answer

For 6 AWG THHN wires in PVC conduit at 40% fill (3+ wires):

  • • 1/2" PVC: 2 wires
  • • 3/4" PVC: 4 wires
  • • 1" PVC: 6 wires

6 AWG in PVC Conduit Fill Chart

Conduit Size Max Wires (40% Fill) Fill % Max Wires (Nipple 60%) Fill %
1/2" 2 36% 3 53%
3/4" 4 40% 6 60%
1" 6 37% 9 55%
1-1/4" 11 39% 16 57%
1-1/2" 15 38% 23 59%
2" 25 39% 38 59%
2-1/2" 43 40% 64 60%
3" 68 40% 102 60%
3-1/2" 89 40% 134 60%
4" 112 40% 169 60%

Understanding the Fill Chart

According to NEC (National Electrical Code) Chapter 9, Table 1, the maximum conduit fill percentage depends on the number of conductors:

  • 1 conductor: 53% fill maximum
  • 2 conductors: 31% fill maximum
  • 3 or more conductors: 40% fill maximum
  • Nipples (24" or less): 60% fill maximum

This chart shows the maximum number of 6 AWG THHN conductors that can fit in each PVC conduit size while maintaining NEC compliance.

Calculation Example

Question: How many 6 AWG THHN wires can fit in 3/4" PVC conduit?

Wire area: 0.0507 sq in per conductor

Conduit internal area: 0.508 sq in

Allowable fill (40%): 0.2032 sq in

Maximum wires: 0.2032 ÷ 0.0507 = 4 wires

Answer: You can fit up to 4 wires of 6 AWG THHN in 3/4" PVC conduit.

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