ICC Residential Electrical Inspectors Practice Exam

What is the maximum size of aluminum conductors permitted for feeders and branch circuits?

1. 10 AWG

2. 12 AWG

3. 8 AWG

4. 6 AWG

The correct answer is: 12 AWG

The maximum size of aluminum conductors permitted for feeders and branch circuits is a critical piece of information in residential electrical work. For feeders and branch circuits, the National Electrical Code (NEC) generally allows conductors of larger sizes to be used for specific applications, but for standard residential feeders and branch circuits, the commonly accepted maximum size of aluminum conductors is indeed 12 AWG. Using a 12 AWG aluminum conductor provides adequate current-carrying capacity for many residential applications while also ensuring safety and compliance with local codes. Conductors that are too small may lead to overheating and potential fire hazards, while larger conductors may not be necessary for typical feeder and branch circuit applications. In the context of the other options, a maximum size of 10 AWG, 8 AWG, or 6 AWG aluminum conductors is permissible in certain specialized applications or for specific load requirements, but for general feeders and branch circuits, these sizes exceed the standard maximum allowed under typical conditions outlined in the NEC.