Texas Residential Wireman Electrician Exam: Complete 2026 Study Guide
You've put in the work on the job site. Now it's time to pass the paper test. The Texas Residential Wireman Electrician exam is administered by PSI on behalf of TDLR, and it's a real book of knowledge — 80 scored questions, open NEC, four hours on the clock. Pass it and you walk out with a credential that opens doors across the state. This guide breaks down exactly what's on the exam, how it's structured, and how to prepare so you're ready when it counts. Start by taking our free practice exam to see where you stand right now.
Texas Residential Wireman Electrician Exam Overview
Here are the numbers you need to know:
- Scored questions: 80
- Non-scored (pilot) items: 5 (these do not count toward your score)
- Time limit: 240 minutes for the 80 scored questions, plus an additional 20 minutes allocated for the 5 non-scored items
- Passing score: 70% — that means you need at least 56 of the 80 scored questions correct
- Exam fee: $64
- Format: Open book — you bring your NEC
The exam is computer-based and administered at PSI testing centers. Questions are multiple choice. A few may be true/false style. You'll need to look things up fast, so knowing your NEC layout cold is half the battle.
Note: Effective September 1, 2026, TDLR exams reference the 2026 NEC. Check the official exam bulletin for the current code edition required on your test date.
Topics Covered on the Texas Residential Wireman Electrician Exam
The exam pulls from ten topic areas. Here's what's weighted most heavily — study these first.
Electrical Services, Service Equipment, and Separately Derived Systems — 16 items
The biggest slice of the exam. You'll see questions on service conductor clearances, disconnecting means requirements, entrance conductor sizing, and grounding/bonding. Know your ampacity rules and how many service disconnects are allowed.
Branch Circuit Calculations and Conductors — 14 items
Minimum conductor sizing, continuous load calculations, GFCI and AFCI protection requirements by location, and branch circuit ratings. NEC Articles 210 and 240 are your anchors here.
Electrical Equipment and Devices — 12 items
Switch types and ratings, receptacle requirements, luminaire placement rules (especially in wet or damp locations), panelboard installation, and motor branch-circuit sizing.
Electrical Wiring Methods and Electrical Materials — 10 items
Conductor insulation ratings, cable protection through framing members, underground cover depths, Type NM/NMC cable requirements, and box fill calculations.
Definitions, Calculations, Theory, and Plans — 8 items
Load calculations using demand factors, NEC code structure, grounding electrode systems, and overcurrent protection sizing. Dwelling unit calculations show up here — know the lighting, small appliance, and laundry circuit rules.
Special Occupancies, Equipment, and Conditions — 7 items
Hazardous location classifications (Class I, II, III; Division 1 vs. 2), material group designations, approved protection techniques, and sealing requirements.
Electrical Feeders — 7 items
Feeder ampacity rules (the 125% continuous load rule), overcurrent protection, demand factor calculations for dwelling and multifamily occupancies, and ground-fault protection for large disconnects.
Motors and Generators — 2 items
Motor conductor sizing, overload protection selection, short-circuit protective device ratings from Table 430.52, and disconnecting means requirements.
Electrical Control Devices and Disconnecting Means — 2 items
Switch connection rules, motor disconnecting means, panelboard overcurrent protection, and motor controller requirements.
Renewable Energy Technologies — 2 items
Photovoltaic systems and electric vehicle charger installations.
Sample Texas Residential Wireman Electrician Exam Questions
Here are five sample questions from different topic areas. Try them before you peek at any resources — see what you actually know.
Question 1 — Electrical Feeders (Easy)
When more than one ampacity value applies for a given circuit length, which value must be used?
- A) The lowest value
- B) The value determined by the engineer
- C) The average of the two values
- D) The highest value
Question 2 — Electrical Equipment and Devices (Hard)
Office furnishings that are mechanically contiguous and electrically connected can exceed 9.0 m (30 ft) when assembled if they use a single flexible cord and plug connection.
- True
- False
Question 3 — Electrical Services, Service Equipment, and Separately Derived Systems (Medium)
For portable power feeder cables over 2000 volts, what is the minimum conductor size permitted?
- A) 12 AWG copper
- B) 10 AWG copper
- C) 8 AWG copper
- D) 6 AWG copper
Question 4 — Electrical Wiring Methods and Electrical Materials (Medium)
Where a cable-type wiring method is installed parallel to framing members such as studs or joists, the nearest outside surface of the cable must be not less than ______ from the nearest edge of the framing member where nails or screws are likely to penetrate.
- A) 3/4 inch
- B) 1 inch
- C) 1-1/4 inches
- D) 1-1/2 inches
Question 5 — Electrical Feeders (Medium)
For equipment grounding conductors 4 AWG and larger, if the insulation does not comply with the standard green color identification, how must the conductor be identified at the time of installation?
- A) By wrapping white tape at each termination point only
- B) By attaching a metal tag at one end only
- C) No additional identification is required for conductors 4 AWG and larger
- D) By permanently identifying it as an equipment grounding conductor at each end and at every accessible point
Don't look up the answers just yet. Take our free practice exam and test your instincts against questions drawn from the same topic areas as the real test.
What Types of Questions to Expect
Here's a breakdown of every topic area and what our practice question bank includes for each one.
Definitions, Calculations, Theory, and Plans — Expect demand factor math, dwelling unit load calculations (lighting at 3 VA/sq ft, two small appliance circuits, the laundry circuit), and questions about mandatory vs. permissive NEC language. You'll also see grounding electrode system questions and overcurrent protection sizing.
Electrical Services, Service Equipment, and Separately Derived Systems — Overhead and underground clearance numbers, service disconnect rules (location, rating, maximum count), ampacity of service entrance conductors, and bonding requirements.
Electrical Feeders — The 125% continuous load rule, demand factor calculations for multifamily buildings, conductor sizing with correction and adjustment factors, and ground-fault protection thresholds for large feeder disconnects.
Branch Circuit Calculations and Conductors — Continuous load sizing under Articles 210.19 and 215.2, OCPD selection under 210.20 and 240.4, GFCI and AFCI location requirements, and permissible loads by circuit rating.
Electrical Wiring Methods and Electrical Materials — Insulation type and temperature rating, protection requirements through framing members, underground cover depth by wiring method, NM cable securing intervals, and box fill calculations.
Electrical Equipment and Devices — Switch ratings and dimmer compatibility, receptacle types (CO/ALR, tamper-resistant, weather-resistant), luminaire placement in closets and bathrooms, and panelboard installation requirements.
Motors and Generators — Branch-circuit conductor sizing at 125% of full-load current, overload protection trip current percentages, maximum fuse and circuit breaker ratings from Table 430.52, and disconnecting means location and in-sight requirements.
Electrical Control Devices and Disconnecting Means — Grounded conductor switching rules, switch and circuit breaker ratings, motor controller design and marking requirements.
Special Occupancies, Equipment, and Conditions — Class I, II, and III hazardous location classifications, material group designations, explosionproof and dust-ignitionproof equipment requirements, permitted wiring methods by division, and conduit sealing rules.
Renewable Energy Technologies — PV system wiring, array sizing, disconnecting means, and EV charger circuit requirements.
Total practice questions available across all topics: 1,248.
Required and Recommended Study Materials
Required: NEC 2026
You need the NEC 2026 at the exam. No NEC, no exam. Buy a soft-bound copy — loose-leaf, spiral-bound, and ring-bound editions are not allowed at the test site. Note that starting September 1, 2026, TDLR will reference the 2026 NEC; confirm which edition applies on your test date.
Tab It Right
You're allowed to tab your NEC before the exam, but only with permanent index tabs manufactured and/or provided by the NEC book publisher. Homemade, DIY, or other third-party tabs are prohibited; candidates who arrive with them must remove them, test without the book, or forfeit the exam fee.
Highlight Strategically
You can highlight and underline your NEC before the exam (just not during the session). Sharpie Tank Highlighters work well for this — bright fluorescent ink, chisel tip for both wide highlighting and margin notes, and they resist smearing once dry. Use different colors for different topics (calculations, grounding, overcurrent protection) so your eye finds the right section fast.
Study Tips for the Texas Residential Wireman Electrician Exam
Study by exam weight, not by NEC article order. Services and branch circuits together make up 30 of the 80 scored questions. Start there. Motors and renewables are only 4 questions combined — don't ignore them, but don't let them eat your calendar.
Practice under timed conditions. A PDF study guide on your couch is useful for learning; it's not useful for building exam pace. Our full practice exam matches the real format — 80 questions, same time limit, same topic breakdown — so you're not guessing at the test-day rhythm.
Know where things live in the NEC. You're not memorizing the whole book. You're learning to navigate it fast. Practice finding load calculation tables, ampacity correction factors, and GFCI/AFCI requirement sections until it's automatic.
Don't spiral on hard questions. Answer what you know, flag what you don't, move on. Come back with fresh eyes. A little exam anxiety is normal — if you feel it taking over, take a few slow breaths and reset. The clock keeps running during breaks, so use any downtime efficiently.
Take the free practice exam first to find your weak spots, then use the full exam for serious, timed prep.
Ready to Pass?
The Texas Residential Wireman Electrician exam is a serious test, but it's a fair one. You know this work. The goal now is translating that knowledge into correct answers under timed, test-room conditions. Get your NEC tabbed, know the heavy topics cold, and practice in exam format before you sit for the real thing.
Start with the free practice exam — 10 questions, no account needed, no cost. See how you do. If you want full prep with 80 timed questions and a topic-by-topic score breakdown, upgrade to the full practice exam. For licensing requirements and eligibility, visit the state licensing website.
You've got this. Go pass it.