Conduit fill per NEC, no table lookups
NEC Chapter 9 conduit fill is part of cable sizing — not a separate step. ekx calculates fill percentage, selects the right trade size, and applies derating factors automatically.
What you get
Conductor cross-sectional areas from NEC Chapter 9, Table 5 and Table 8 for fill calculations.
Conduit trade size selected to meet NEC fill requirements based on conductor count and sizes.
Conduit fill percentage calculated and displayed. Overfilled conduits flagged automatically.
Conduit fill count feeds directly into ampacity derating factor calculations per NEC 310.15.
EMT, RMC, IMC, PVC, and other conduit types with correct internal areas.
Conduit fill is calculated from the actual conductors in each circuit — not a standalone calculator.
Conduit fill as part of cable sizing
Standalone conduit fill calculators make you enter conductor sizes manually. In ekx, the conductors are already sized — conduit fill is just another property of the circuit.
- Conductors are already sized — fill calculates from actual circuit data
- Trade size selected to meet NEC maximum fill percentages
- Conductor count feeds into ampacity derating automatically
- Change a conductor size and conduit fill recalculates instantly
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View All PlansFrequently asked questions
NEC Chapter 9, Tables 1 (fill percentages), 4 (conduit dimensions), 5 (insulated conductor areas), and 8 (bare conductor areas).
Yes. Fill calculations properly handle mixed conductor sizes in the same conduit, using the 40% fill limit for 3+ conductors per NEC Chapter 9, Table 1.
Yes. The number of current-carrying conductors in a conduit feeds directly into the ampacity derating calculation per NEC 310.15(C).
EMT, RMC, IMC, PVC Schedule 40 and 80, and other standard conduit types. Each uses the correct internal cross-sectional area from NEC tables.
Conduit fill that calculates itself.
NEC Chapter 9. No table lookups. Integrated with cable sizing.
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