---
name: "journeyman_electrician_exam_prep"
description: "Prepare a working apprentice for a journeyman electrician licensing exam: run a diagnostic that maps weak areas to NEC chapters and articles, teach the lookup first method for an open book test, drill the calculation families (load, conduit fill, voltage drop, ampacity, motors), and build an eight week study plan that fits around full work days. Use when someone is studying for a journeyman, journey level, or general electrician exam, asks how to find answers in the NEC, or keeps failing practice tests."
---

# Purpose

Pass an open book code test, which is a different skill from knowing the trade. Most journeyman exams do not test whether the candidate memorized the National Electrical Code. They test whether the candidate can find the right rule in the right article, fast, and work the standard calculations without arithmetic slips. This skill trains that: diagnostic first, lookup speed second, calculation drills third, timed full practice last.

State rules control everything. Before any study plan, pin down the candidate's own exam from the licensing board's candidate information bulletin: which NEC edition, open or closed book, question count, time limit, passing score, what book binding and tabs are allowed, and what calculator is allowed. Formats vary hard by state. Texas, for example, splits the exam into an NEC Knowledge portion (59 questions in 130 minutes) and a Calculations portion (26 questions in 110 minutes), each passed at 70 percent, open book. Other states run a single 80 to 100 question exam over 4 to 5 hours, also commonly passed at 70 percent. Never study to a format borrowed from another state.

# Workflow

## 1. Pin the target exam

- Get five facts from the board or its testing vendor (PSI and Pearson VUE run most states): NEC edition tested, portions and question counts, minutes per portion, passing score, and the book and calculator rules for the room.
- Record the eligibility facts too. The common pattern is about 8,000 hours of supervised experience, roughly four years full time, plus classroom hours that vary by state (Montana, for example, pairs 8,000 practical hours with 576 hours of related instruction). Some states let a candidate test a few hundred hours early and issue the license when the hours complete. Verify the candidate's state, do not assume.
- Do the time math and write it down: minutes divided by scored questions is the budget. 130 minutes over 56 scored questions is about 2.3 minutes per question. Every drill after this point runs against that budget.

## 2. Run the diagnostic

Give a 50 question diagnostic, untimed but with lookup time noted per question, spread across the map in `references/nec-map.md`:

- 6 on general rules and definitions (Articles 90, 100, 110)
- 12 on wiring and protection (Articles 210, 215, 220, 230, 240, 250)
- 10 on wiring methods and ampacity (Articles 300, 310, 314, plus Chapter 9)
- 8 on equipment (Articles 404, 406, 408, 430, 440)
- 6 on special occupancies, special equipment, and special conditions (Chapters 5, 6, 7)
- 8 calculations (load, fill, voltage drop, ampacity, motor)

Score it three ways, not one:

1. Percent correct per chapter group. Anything under 70 percent is a weak area.
2. Lookup failures: questions the candidate could not locate in the book at all. These are navigation problems, not knowledge problems, and they are the fastest points to win back.
3. Calculation failures split into wrong method versus arithmetic slip. Wrong method needs teaching. Arithmetic slips need a written step routine and slower, checked work.

Map every miss to its article before assigning study. A score with no article map is just a grade.

## 3. Teach the lookup first method

This is the core of the skill. Drill it until it is a habit:

1. Read the question and pull out the one or two keywords that name the subject: the equipment, the occupancy, the wiring method. Ignore the story around them.
2. Guess the chapter from the keyword before touching the index. Services, feeders, branch circuits, grounding: Chapter 2. Conduit, cable, boxes: Chapter 3. Motors, HVAC, panels in use: Chapter 4. A location type (health care, hazardous, assembly): Chapter 5. A machine type (signs, pools, solar): Chapter 6.
3. Go to the index at the back of the NEC under the keyword, note the article, and open the article, not a search engine memory of it.
4. Inside the article, scan the part headings first. Large articles are split into parts, and the part title usually names the exact situation in the question.
5. Read the section, then read its exceptions before answering. Exam writers put the tested twist in the exception often enough that skipping exceptions is a known way to lose points.
6. If the section points to a table, the table and its notes are part of the answer. Read the notes under the table, especially in Chapter 9.
7. Answer, mark the article number next to the question, and move on. On the real exam, flag any question not found in about 2 minutes, guess, and return on the second pass. One stubborn lookup can eat the time for three easy questions.

Speed standard to train toward: a familiar topic found in under 60 seconds, an unfamiliar one in under 2 minutes. Time lookups in practice with a phone timer, separate from answering time.

Book setup matters and rules differ by room. Where the bulletin allows tabs, tab the high traffic stops: Articles 100, 210, 220, 230, 240, 250, 300, 310 including Table 310.16, 314, 334, 358, 408, 430 including its full load current tables, 680, and Chapter 9 Tables 1, 4, 5, and 8, plus Annex C and Annex D. Some rooms allow only publisher installed tabs and only a soft bound book, and ban loose leaf and spiral bound copies, so check the bulletin before buying or tabbing anything. Highlighting and handwritten notes are also rule dependent. Never tell a candidate a setup is legal without the bulletin saying so.

## 4. Drill the calculations

Run each family as a written routine, same steps every time, using `scripts/calc.py` to check work. Show every step on paper in practice, because the exam slip is usually a skipped step, not a hard concept.

### Load calculations, Article 220 standard method

1. General load: floor area in square feet times 3 VA, plus 1,500 VA per small appliance circuit (minimum two), plus 1,500 VA for the laundry circuit.
2. Apply the dwelling demand factors to that sum: first 3,000 VA at 100 percent, the rest up to 120,000 VA at 35 percent, anything over at 25 percent. The table number moved between editions (Table 220.42 in 2020, Table 220.45 in 2023), so cite the candidate's edition.
3. Dryer: 5,000 VA or nameplate, whichever is larger.
4. Cooking equipment: use Table 220.55. A single range rated not over 12 kW takes an 8,000 VA demand from Column C.
5. Heating versus air conditioning: take the larger one only, they do not run at the same time.
6. Fixed appliances: four or more fastened in place appliances (not dryer, range, heat, or AC) take a 75 percent demand factor under 220.53.
7. Add 25 percent of the largest motor load.
8. Divide total VA by the service voltage, 240 for a typical single phase dwelling, and round up to a standard size.

Check with: `python3 scripts/calc.py load --sqft 2000 --dryer-va 5000 --range-va 12000 --ac-va 4800 --fixed-va 6000 --fixed-count 4 --largest-motor-va 4800` which returns 29,125 VA and 121.4 A. Use the standard method on exams unless the question names the optional method in 220.82.

### Voltage drop

- Single phase: VD = 2 x K x I x D / CM. Three phase: replace the 2 with 1.732.
- K is 12.9 for copper and 21.2 for aluminum at 75 degrees C. D is the one way distance in feet, not the round trip. CM is the circular mil area from Chapter 9 Table 8.
- Worked check: 6 AWG copper, 44 A, 240 V, 160 ft one way. CM for 6 AWG is 26,240. VD = 2 x 12.9 x 44 x 160 / 26,240 = 6.9 V, which is 2.9 percent, load sees 233.1 V. Run it: `python3 scripts/calc.py vd --amps 44 --feet 160 --cm 26240 --volts 240`
- Sizing form: CM = 2 x K x I x D / allowed VD. Run: `python3 scripts/calc.py size --amps 20 --feet 150 --vd-percent 3 --volts 120`
- Teach the status of the limits honestly: the 3 percent branch circuit and 5 percent total figures sit in informational notes, which are guidance, not enforceable rules, but exam questions still test against them. Say that out loud so the candidate does not cite them as mandates in the field.

### Conduit fill, Chapter 9

1. Count every conductor, including equipment grounding conductors and neutrals.
2. Get each conductor's area from Table 5. Get the raceway's total internal area from Table 4.
3. Apply Table 1 limits: one conductor 53 percent, two conductors 31 percent, more than two 40 percent. A nipple 24 inches or shorter between enclosures may fill to 60 percent under Note 4, and the ampacity adjustment factors do not apply there.
4. Same size and same insulation throughout: skip the math and use the Annex C tables, they are built from Table 1.
5. Rounding for equal size conductors follows Note 7: a fraction of 0.8 or larger rounds up to one more conductor.

Run: `python3 scripts/calc.py fill --conductors "12:9" --raceway emt --trade 3/4` and `python3 scripts/calc.py fill --conductors "6:5" --raceway emt --trade 1`. Then state the trap: passing fill does not settle ampacity. Four or more current carrying conductors in one raceway triggers the adjustment factors in 310.15(C)(1), a separate check.

### Ampacity and motors

- Start in Table 310.16 under the column that matches the insulation rating, at 30 degrees C ambient and no more than three current carrying conductors. Copper at 75 degrees C, the column most terminations force: 12 AWG 25 A, 10 AWG 35 A, 8 AWG 50 A, 6 AWG 65 A, 4 AWG 85 A, 3 AWG 100 A, 1/0 150 A, 4/0 230 A.
- Then apply, in order: ambient correction, the adjustment factor for more than three current carrying conductors, the termination limit in 110.14(C), and the small conductor overcurrent caps in 240.4(D) (15 A for 14 AWG copper, 20 A for 12, 30 A for 10, regardless of the higher table ampacity).
- Continuous loads size at 125 percent in 210.19 and 215.2.
- Motors are their own routine, Article 430: use the full load current tables at the end of Article 430 for conductor and protection sizing, not the motor nameplate. Nameplate current governs the overload device. Mixing those two up is the classic motor question trap. Conductor ampacity is 125 percent of table full load current under 430.22.

## 5. Build the eight week plan

Full plan with daily blocks is in `references/study-plan.md`. The shape, sized for someone working full days:

- Weeks 1 to 2: diagnostic, book setup, lookup drills only. Weekday sessions 45 to 60 minutes before or after shift, one 2 hour weekend session. No calculation teaching yet, navigation is the bottleneck for most candidates.
- Weeks 3 to 5: one calculation family per week in rotation with the two weakest chapter groups from the diagnostic. Every session ends with 10 timed lookup questions.
- Week 6: mixed timed sets at the real per question budget. Second diagnostic, same scoring, compare article by article.
- Week 7: two full timed practice exams on separate days, full review of every miss mapped to its article, no new material.
- Week 8: light review of the personal miss list only, book and calculator check against the bulletin, early night before the exam. Nothing new in the last 48 hours.

Session rule that keeps the plan alive on work days: a session can shrink to 20 minutes of lookup drills, it cannot be skipped twice in a row. Tired evening sessions do lookups and flash review, calculations go to mornings and weekends when the head is clear.

## 6. Exam day routine

- First pass: answer what you can find fast, flag the rest, never let one question take more than about twice the per question budget.
- Second pass: flagged questions with fresh eyes, starting with calculation questions, which carry the same weight and are often winnable with the routine.
- Use the calculator the bulletin allows and the one practiced with. Recheck every calculation once by re-running the steps in a different order or estimating the size of the answer.
- If the state splits knowledge and calculations into portions with separate pass marks, a strong portion does not rescue a weak one. Pace each portion on its own clock.

# Output Contract

When running this skill, produce:

1. The target exam fact sheet: state, vendor, NEC edition, portions, questions, minutes, per question budget, passing score, book and calculator rules, each traced to the board bulletin.
2. The diagnostic report: percent by chapter group, lookup failures listed by article, calculation failures split into method versus arithmetic.
3. A study plan fitted to the candidate's work schedule, in the eight week shape above or compressed with the tradeoffs stated.
4. Calculation drill sets with worked answers and the article or table cited for each, checkable with `scripts/calc.py`.
5. A personal miss list: the candidate's repeated articles and traps, reviewed in the final week.

# Operating Rules

1. Never state an exam format, fee, passing score, NEC edition, or book rule for a state without the board bulletin or vendor page behind it. Formats differ by state and change between cycles.
2. Never invent NEC section numbers, table values, or demand factors. Verify in the candidate's edition or in `references/`. If a value cannot be verified, cut it.
3. Teach lookup before memorization. A fact the candidate cannot find in the room is worth nothing on an open book exam.
4. Separate the checks that exams love to merge: fill versus ampacity adjustment, table full load current versus nameplate, voltage drop guidance versus enforceable rule, standard versus optional load method.
5. This skill prepares people for an exam. It is not a substitute for the code in the field, and it never blesses an installation. Field work follows the adopted code, the authority having jurisdiction, and the permit process.
6. No em dashes in anything this skill writes for the candidate.