JoshTheSparky works through 10 Brain Buster questions based on the 2026 National Electrical Code (NEC). These questions come from the weekly Question of the Week series on NECChat and were compiled into a 10-question study packet.

⚡ The 10 Brain Busters

1 — Motor Calculations A 5 HP, 230V single-phase motor with a 1.15 service factor and 22A nameplate current. The question covers branch-circuit conductor sizing and the maximum initial overload setting under 430.32(A)(1).

2 — Box Fill How many #12 AWG THHN conductors can be installed in a 4" × 4" metal box that is 1½" deep? A practical breakdown of box volume and conductor volume allowances.

3 — IMC What is the maximum trade size permitted for IMC? This question focuses on finding the appli ...