The maximum proportion of a conduit's cross-section that conductors may occupy.
The limit exists so that conductors can be pulled without damage and so heat can escape. It is typically 40% for three or more conductors, with higher allowances for one or two.
Fill is calculated on the conductor's outside diameter including insulation, not on its cross-sectional area of copper. That is why the same copper area in thicker insulation may not fit.
Calculating conduit fill from the conductor's copper area. Fill is based on overall diameter with insulation.
This site uses Google Analytics to count visits and see which pages are useful. It sets cookies only if you agree. See the privacy policy.