How many #10 THW conductors can be placed in a 2 inch ENT nipple that already contains 35 #12 THHN conductors?

To determine how many #10 THW conductors can be placed in a 2-inch ENT (Electrical Nonmetallic Tubing) nipple that already contains 35 #12 THHN conductors, we first need to consider the conduit fill requirements as outlined in the National Electrical Code (NEC).

The NEC specifies that the total fill of conductors in a conduit must not exceed certain percentages to ensure safety and avoid overheating. For a conduit with multiple types of conductors, we typically need to calculate the allowable fill based on the size and type of conductors involved.

A 2-inch ENT conduit has a specific allowable fill rate calculated in terms of the cross-sectional area of the conduit and the individual areas of the conductors it contains. The total number of conductors is determined by combining these areas, using a formula or referencing tables provided in the NEC.

For #12 THHN conductors, you can place a significant number in a 2-inch NIC. When already filled with 35 #12 THHN conductors, you then calculate how many additional #10 THW conductors can fit.

Typically, the filling capacity of a conduit is defined such that the entire volume of the available conduit space—after accounting for the existing conductors