For eight 12 AWG THW copper conductors in the same EMT, what is the minimum EMT size required?

To determine the minimum EMT size required for eight 12 AWG THW copper conductors, we can reference the National Electrical Code (NEC). Each 12 AWG conductor has a certain cross-sectional area, and the total conductor fill must not exceed the allowable fill for the conduit size.

First, we need to find the allowable fill capacity for EMT conduits. For individual conductors, the NEC generally states that a maximum of 40% fill is permitted in a conduit when more than two conductors are bundled together.

For 12 AWG THW copper conductors, the approximate diameter for each conductor is about 0.1 inches, giving them a cross-sectional area that can be found in NEC tables. When calculating the total area needed for eight conductors, you'll have to use the formula for the area of the circle and multiply it by the number of conductors, then compare that value against the fill capacity of available EMT sizes.

The 3/4” EMT conduit has an overall capacity that becomes critical in determining whether it can accommodate the eight conductors at the required fill percentage. After going through the calculations and ensuring that the total area of the conductors does not exceed 40% of the cross-sectional area of