Only 1 in 5 candidates passes the calculations part. Practice every calculation type with fresh numbers each time, see the worked solution, and learn which 2026 NEC table to open. In English and Spanish.
Sources: TDLR exam statistics FY2025, PSI candidate bulletin. All pass rates.
Real exam-style calculations. Answer, then open the worked steps.
Each problem uses new numbers, so you practice the method rather than memorizing an answer.
Pick the answer: sizes and ratings come from your code book.
The format from the PSI bulletin updated September 15, 2026. You need 70% to pass.
Two parts since March 2025: 59 NEC knowledge questions in 130 minutes and 26 calculation questions in 110 minutes. Pass each part with 70%.
| Part | Questions | Time |
|---|---|---|
| NEC knowledge | 59 | 2 h 10 min |
| Calculations | 26 | 1 h 50 min |
Fee $78 · 8,000 hours of experience
Two parts: 75 NEC knowledge questions in 150 minutes and 33 calculation questions in 170 minutes, heavy on services, feeders and motors.
| Part | Questions | Time |
|---|---|---|
| NEC knowledge | 75 | 2 h 30 min |
| Calculations | 33 | 2 h 50 min |
Fee $78 · 12,000 hours of experience
One exam of 85 questions in 4 hours 20 minutes, with dwelling load calculations mixed in among the code questions.
| Part | Questions | Time |
|---|---|---|
| Single exam | 85 | 4 h 20 min |
Fee $64 · 4,000 hours of experience
26 topics, each with a calculator, a worked example and unlimited practice.
Services and feeders for houses and apartments under Article 120.
3 topicsLighting, receptacles and kitchen equipment in other occupancies.
2 topicsAmpacity, derating, voltage drop, continuous loads and breaker sizes.
5 topicsFull-load current, conductors, overloads, branch-circuit and feeder protection.
5 topicsBox fill, conduit fill and pull box sizing.
3 topicsEquipment grounding and grounding electrode conductor sizes.
2 topicsPrimary and secondary current and overcurrent protection.
2 topicsOhm’s law, power, circuits, three-phase and power factor.
4 topicsA fixed question bank teaches you answers. Each problem here is drawn fresh, so you learn the method that works on whatever numbers PSI gives you.
The exam lets you use your own NEC, so speed in the book is the skill. Steps name the article and table to open. We never print NEC tables: you build the habit of finding them.
The 2026 NEC moved load calculations from Article 220 to Article 120 and cut the dwelling feeder and service load to 2 VA per square foot. See the 2026 NEC changes.
Texas offers the exam in Spanish at no extra cost. Every page here exists in both languages, with the terms PSI uses on the Spanish exam.
The 2026 NEC. TDLR adopted it in 16 TAC §73.100, and the PSI exams have used it since Sep 1, 2026. The one Texas amendment keeps 210.8(F) Exception No. 2 for listed HVAC equipment.
Yes. The PSI bulletin says the exams are offered in English and Spanish at no extra cost. Pick the language when you schedule.
Few. In fiscal 2025, 20.6% of 6,328 candidates passed the journeyman calculations part, and 19.1% passed master calculations (TDLR exam statistics).
Yes. Bring your own soft-bound 2026 NEC, highlighted and annotated before the exam. Only permanent publisher tabs are allowed: no homemade tabs, no spiral or ring-bound copies and no Handbook.
No. Every problem is original and generated with fresh numbers each time, so you practice the method instead of memorizing answers. We never print NEC text or tables: problems tell you which table to open in your own book.
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