NEC · By exam topic

The NEC topics the journeyman exam tests most.

A handful of NEC articles make up the majority of the exam. Each topic hub pulls together that area's code rules, the calculators it relies on, the glossary terms behind it, and the questions that test it.

NEC 2017 2020 2023

High-weight exam topics

Ranked by how heavily the journeyman exam leans on each.

Article 250
Grounding & Bonding
Article 250 is the highest-volume topic on the journeyman exam, covering grounding electrode systems, equipment grounding conductors, bonding jumpers, and conductor sizing tables.
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Article 430
Motors
Article 430 requires candidates to size motor branch-circuit conductors, select short-circuit protection, and calculate overload protection—multi-step problems that appear on nearly every journeyman exam.
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Article 220
Load Calculations
Article 220 drives service and feeder sizing for dwelling and commercial occupancies, making it one of the most heavily tested multi-step calculation areas on the journeyman exam.
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Article 314
Boxes & Box Fill
Article 314 box fill calculations test whether candidates can size junction and device boxes based on conductor count, device allowances, and clamp allowances per NEC 314.16.
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Article 310
Conductors & Ampacity
Article 310 and Table 310.16 govern conductor ampacity and temperature-correction derating—foundational knowledge required to size any circuit correctly on the journeyman exam.
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Ch. 9 / 210.19 / 215.2
Voltage Drop
Voltage drop calculations span Chapter 9, 210.19, and 215.2, testing whether candidates can upsize conductors to keep voltage loss within recommended limits for branch circuits and feeders.
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Chapter 9
Conduit & Raceway Fill
Chapter 9 Tables 1, 4, and 5 define the fill percentages and conduit dimensions used to determine how many conductors fit in a given raceway—a frequent exam calculation.
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Article 230
Services
Article 230 specifies service entrance conductor sizing, clearances, number of disconnecting means, and the 2020-edition outdoor emergency disconnect added at 230.85.
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Surveys of the journeyman exam and the electricians who sit it keep pointing at the same five areas — grounding and bonding (Article 250), motor calculations (430), load calculations (220), box fill (314.16), and conductor ampacity (310). Together with voltage drop, conduit fill, and services, they account for the bulk of the questions and most of the retakes.

Each topic hub is built to take you from the rule to the calculation to a timed question, so you're not just reading the code — you're practicing finding and applying it under the clock, which is what the exam actually measures.

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