Wrong move
Direct answer
The risky shortcut is sizing the breaker only from wire color or what was there before. A common NEC starting point is 20 amps for many 12 AWG copper branch-circuit conductors, but conductor type, temperature rating, terminals, load, exceptions, and local amendments matter.
How to use this answer
Read the answer once, then prove it by choosing an answer in a practice question before looking at the explanation. If the miss repeats, tag the domain as NEC field application and drill a smaller set before returning to mixed practice.
Prep path
Journeyman Electrician Study Guide
Independent journeyman electrician study guide for code navigation, calculations, wiring methods, and safety review.
SamplesJourneyman Electrician Sample Questions
Public Journeyman Electrician Practice Test sample questions with explanations.
PracticeOpen Journeyman Electrician Practice Test
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