Conduit Fill Calculator

NEC Tables Used To Calculate Current-Carrying Conductor Rating
NEC Table 310.16 is used to select an insulated conductor rated 0 through 2000 volts, 60°C through 90°C, based on ambient temperature of 30°C, using the selected or calculated ampacity and temperature ratings. For ambient temperatures other than 30°C, temperature correction factors chart is used to adjust NEC Table 310.16 allowable ampacities, using the selected ambient temperature.
NEC Table 310.15(B)(2)(a) is used to adjust allowable ampacities of insulated conductors found in NEC Table 310.16 when more than three current-carrying conductors are in a raceway or cable.
NEC Tables Used To Calculate Equipment Grounding Conductor Rating
NEC Table 430.52 is used to calculate the maximum rating of the selected motor branch circuit, short-circuit and ground fault protective device.
NEC Section 240.6(A) is used to select the actual protective device rating per standard ampere ratings for protective devices, from the maximum device rating calculated in NEC Table 430.52.
NEC Table 250.122 is used to select the minimum equipment grounding conductor rating, for grounding raceway and equipment, from the protective device rating selected in NEC Section 240.6(A).
NEC Tables Used To Select Motor Ampacity
NEC Table 430.248 is used to select the full load amps of single-phase alternating current motors, using the selected voltage and motor ratings, and phase count.
NEC Table 430.250 is used to select the full load amps of three-phase alternating current induction type squirrel cage and wound rotor motors, using the selected voltage and motor ratings, and phase count.
NEC Table Used To Select Conductor Area
NEC Chapter 9 Table 5 is used to calculate the total area of conductors.
NEC Table Used To Calculate Conduit Size
NEC Chapter 9 Table 4 is used to calculate conduit size, through dimensions and percent area of chosen conduit, using the total calculated conductor area.

NOTE: The calculations within the Calculators are based upon National Electric Code (NEC) guidelines, however, the results between the two different calculation methods may vary due to rounding. The results are to be used as a general guideline and EngCalc cannot be held responsible for this information as it pertains to your installation. Proper conductor and conduit selection is the sole responsibility of the installer. Be sure to check local codes.

Conduit Fill Calculator

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