Apprentice corner

How to learn the code book, practice questions with answers, and the path to a license.

Study plan

Get the right edition of the code book for your exam, and tab it. Tabs on the articles you use most save minutes on every question.
Learn the index. Most exam questions are lookups. Practice finding answers from the index, not from memory.
Learn the layout (below). Knowing that receptacle rules live in 406 and 210.52 means you only search two places.
Do calculations by hand until they're automatic: ampacity and derating, box fill, conduit fill, voltage drop, dwelling load, motor circuits, transformers.
Time yourself. Plan on two to three minutes a question. Skip what's slow and come back.
Read the whole question and the exceptions. Many wrong answers come from missing "dwelling unit," "continuous" or an exception.
A little every day beats a weekend cram: 20 questions a day for two months covers the book many times over.

How the code is organized

Articles	What's there
90, 100, 110	How the code works, definitions, general requirements (working space, terminations)
200–250	Neutrals, branch circuits, feeders, load calculations, services, overcurrent protection, grounding and bonding
300–399	Wiring methods and conductors: general rules, ampacity (310), boxes (314), cables and raceways
400–490	Equipment: cords, switches, receptacles, panelboards, luminaires, appliances, motors (430), AC (440), transformers (450)
500–590	Special occupancies: hazardous locations, health care, assembly, temporary power (590)
600–695	Special equipment: signs, EV charging (625), pools (680), solar PV (690), fire pumps
700–770	Special conditions: emergency and standby systems, limited-energy circuits
Chapter 9	Tables: conduit fill, conductor properties, resistance

Chapters 1 to 4 apply everywhere. Chapters 5, 6 and 7 add to or change them for special cases. Chapter 8 (communications) stands on its own. The code lookup points you to the section for common questions.

Practice questions

Find the answer in your code book first, then open it.

1. What is the smallest copper equipment grounding conductor for a circuit on a 60 A breaker?

10 AWG copper. (Table 250.122)

2. How many degrees of bends are allowed between pull points in EMT?

360°, counting offsets, saddles and kicks. (358.26)

3. How close to a box must NM cable be secured?

Within 12 in, then at least every 4½ ft. (334.30)

4. A load of 16 A runs for 3 hours or more. What is the smallest standard breaker?

20 A (16 × 1.25 = 20). (210.20(A))

5. A single ground rod tests above 25 Ω. What then?

Drive a supplemental electrode at least 6 ft away. With two rods you don’t have to test. (250.53(A)(2), 250.53(A)(3))

6. What is the working space depth in front of a 120/240 V panel with nothing grounded across from it?

3 ft (Condition 1, 0–150 V to ground). (110.26(A)(1))

7. What is the full-load current of a 45 kVA three-phase transformer at 208 V?

About 125 A: 45,000 ÷ (208 × 1.732) = 124.9 A. (Formula; see 450.3(B))

8. How many 20 A small-appliance circuits does a dwelling kitchen need at minimum?

Two. (210.11(C)(1))

9. How much free conductor must be left at each box?

At least 6 in, and at least 3 in outside the box opening when the opening is smaller than 8 in. (300.14)

10. What is the largest breaker allowed on 12 AWG copper for a general-purpose circuit?

20 A. (240.4(D))

11. Which column of Table 310.16 do you normally use for a 50 A circuit with terminals marked 60/75 °C?

The 75 °C column, because the equipment is marked for it. Unmarked, it would be 60 °C. (110.14(C)(1)(a))

12. What does the 2.0 multiplier mean when bending a 30° offset?

The distance between the two bends is the offset depth × 2. A 6 in offset needs marks 12 in apart. (Bending geometry: 1 ÷ sin 30°)

Texas licensing (TDLR)

The Texas Department of Licensing and Regulation licenses electricians. Requirements change: confirm hours, fees and exams on the TDLR website before you apply.

License	Typical requirement
Apprentice	Register with TDLR before working, and work under the supervision of a licensed electrician.
Residential wireman	About 4,000 hours of on-the-job training, then the exam.
Journeyman	About 8,000 hours of on-the-job training, then the exam.
Master	About 12,000 hours, a journeyman license held for at least 2 years, then the exam.

Keep your own record of hours, with employer verification, from day one.
Apprenticeship programs (union or open shop) combine the hours with classroom training.
Licenses need continuing education to renew.
Other states have their own boards and requirements, and some have reciprocity agreements with Texas.