PVC Conduit Fill Chart

The PVC conduit fill chart is a table used to determine the maximum number of wires that can be safely installed in PVC conduit tubing based on the size of the conduit and the gauge of the wire. The chart provides information on the allowable number of wires for each combination, taking into account the requirements set forth by the National Electrical Code (NEC) or other applicable standards. It is an essential tool for electricians and engineers working on wiring projects that involve PVC conduits.

The PVC conduit fill table helps calculate the safe number of THWN or THHN wires that can fit in PVC conduit tubing. It lists conduit sizes (Schedule 40 or 80) horizontally and wire gauges (AWG or MCM) vertically to display the maximum number of wires allowed for each combination according to the 2020 NEC code.

Trade Size
in Inches
                                                         Wire Size (THWN, THHN)                                      Conductor Size AWG/kcmil
14 12 10 8 6 4 3 2 1 1/0 2/0 3/0 4/0 250 300 350 400 500 600 700 750
1/2 40 11 8 5 3 1 1 1 1 1 1
80 9 6 4 2 1 1 1 1
3/4 40 21 15 9 5 4 2 1 1 1 1 1 1 1
80 17 12 7 4 3 1 1 1 1 1 1 1
1 40 34 25 15 9 6 4 3 3 1 1 1 1 1 1 1 1
80 28 20 13 7 5 3 3 2 1 1 1 1 1 1
1-1/4 40 60 43 27 16 11 7 6 5 3 3 2 1 1 1 1 1 1 1 1
80 51 37 23 13 9 6 5 4 3 2 1 1 1 1 1 1 1 1
1-1/2 40 82 59 37 21 15 9 8 7 5 4 3 3 2 1 1 1 1 1 1 1 1
80 70 51 32 18 13 8 7 6 4 3 3 2 1 1 1 1 1 1 1 1 1
2 40 135 99 62 36 26 16 13 11 8 7 6 5 4 3 3 2 1 1 1 1 1
80 118 86 54 31 22 14 12 10 7 6 5 3 3 2 1 1 1 1 1 1 1
2-1/2 40 193 141 89 51 37 22 19 16 12 10 8 7 6 4 4 3 3 2 1 1 1
80 170 124 78 45 32 20 17 14 10 9 7 6 5 4 3 3 3 2 1 1 1
3 40 299 218 137 79 57 35 30 25 18 15 13 11 9 7 6 5 5 4 3 3 2
80 265 193 122 70 51 31 26 22 16 14 11 9 8 6 5 5 4 3 3 2 2
3-1/2 40 401 293 184 106 77 47 40 33 25 21 17 14 12 10 8 7 6 5 4 4 3
80 358 261 164 95 68 42 35 30 22 18 15 13 10 8 7 6 6 5 4 3 3
4 40 517 377 238 137 99 61 51 43 32 27 22 18 15 12 11 9 8 7 5 5 4
80 464 338 213 123 89 54 46 39 29 24 20 17 14 11 9 8 7 6 5 4 4
5 40 815 594 374 216 156 96 81 68 50 42 35 29 24 20 17 >15 13 11 9 8 7
80 736 537 338 195 141 86 73 61 45 38 32 26 22 18 15 13 12 10 8 7 7
6 40 1178 859 541 312 225 138 117 98 73 61 51 42 35 28 24 21 19 16 13 11 11
80 1055 770 485 279 202 124 105 88 65 55 46 38 31 25 22 19 17 14 12 10 9

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