Calcolatore Riempimento Canalina Gratuito
Calcola la percentuale di riempimento delle canaline secondo le normative NEC.
sq in
sq in
Conduit Fill
45.0 %
NEC Max Fill40 %
Remaining Area-0.0436 sq in
Conduit Fill vs Conduit Internal Area
Formula
NEC Conduit Fill Rules
The National Electrical Code limits fill percentages to prevent overheating:
Calculate fill by dividing total conductor area (including insulation) by the conduit internal area.
Esempio Risolto
4 conductors of 12 AWG THHN (0.0973 sq in each) in 3/4-inch EMT (0.864 sq in).
- 01Total wire area = 4 x 0.0973 = 0.389 sq in
- 02Fill = 0.389 / 0.864 x 100 = 45.0%
- 03NEC allows 40% for 3+ conductors
- 04This conduit is overfilled; upsize to 1-inch EMT.
Domande Frequenti
Where do I find wire and conduit areas?
NEC Chapter 9, Tables 4 and 5 list internal areas for common conduit types and conductor areas with insulation by wire type and gauge.
Do ground wires count toward fill?
Yes, equipment grounding conductors must be included in the fill calculation. Only internal conduit nipples 24 inches or less are exempt from the 40% rule.
Impara