Electrician License Exam Study App

⚡ The Most Important Thing Nobody Tells You

Read the entire test before answering Question 1.

Many state licensing exams weight the final questions more heavily than the early ones. On some tests the last 10 questions are worth 5 points each — that's 50 points out of a 70-point passing score. If you work front-to-back at a steady pace you may run out of time before reaching the high-value questions and fail despite knowing the material.

Strategy: scan the point values first, then answer the highest-value questions before time pressure builds.

"I held licenses in 38 states. I could take 3 tests per day at the national testing center once I understood the pattern. But Washington State didn't use the same company — and I failed twice. A fellow applicant who had just passed on his 6th attempt explained it: Washington weighted the last questions heavily. Everyone started at question 1 and ran out of time. Once you knew to start at the end, the test became passable."

— Field-tested advice from a 38-state Master Electrician

Before the Exam

✓ Know which NEC edition your state uses. Not the current NFPA publication — the edition your state has actually adopted. These can differ by several years. Call your state licensing board if unsure.

✓ Bring your code book and know how to use it. Most state exams are open-book for the NEC portion. Speed matters — know the index, the table of contents, and where the key tables are (310.16, 430.52, 220.42, etc.) before test day.

✓ Memorize the key numbers. You can look up article numbers but knowing 125%, 3 VA/ft², 5 mA, 10 ft, 360° cold saves time you can't afford to waste.

✓ Check the calculator policy. Some exams allow a basic calculator; others don't. Practice both ways. The math on most exams is designed to be doable with simple arithmetic.

✓ Eat before you go. Sounds obvious. People fail exams because they're hungry and tired, not because they don't know the material.

During the Exam

→ First 2 minutes: scan the entire test. Count the questions. Find the point values. Identify the high-value questions at the end. Note any calculation questions that will take time.

→ Answer the high-value questions first. If the last 10 are worth 5 points each and the rest are worth 1 point each, do the math on where you need your time.

→ Skip and return. If a question stumps you, mark it and move on. Don't let one question cost you three others.

→ For open-book NEC questions, go straight to the index. Look up the keyword, not the topic. "Conductor, ampacity" is faster than browsing Article 310.

→ Your first answer is usually right. Don't second-guess unless you find a specific code reference that contradicts your choice.

Washington State — Electrical Administrator

Washington State does not license Master Electricians the way most states do. Instead, electrical contractors must employ a licensed Electrical Administrator — a person qualified to sign off permits and supervise electrical work for the company. The role is functionally equivalent to a Master Electrician.

Washington's exam has historically been administered independently (not by the national testing companies) and is structured differently. The point-weighting strategy described above has been critical for many test-takers.

If you are testing in Washington: confirm current point weighting with the Department of Labor & Industries before your exam date, as the format can change.

State Licensing — Key Facts

Most state exams use a shared question database administered by national testing companies (PSI Exams, Prometric, and others). This means the core question pool is similar across many states.

Journeyman vs. Master content: Journeyman exams focus on installation — code, wiring methods, theory. Master exams add business law, contracts, taxes, estimating, labor law, and project management. Know which you're taking.

Reciprocity varies widely. Some states honor other states' licenses; most require their own exam. Endorsement (accepting another state's license) is different from reciprocity (mutual recognition).

CE for renewal: Most states require 24–120 hours of continuing education every 3 years (aligned with the NEC cycle). Code update courses are accepted in most states. Keep records — you'll need them at renewal.

Always verify with your state licensing board — exam formats, accepted reference materials, pass scores, and CE requirements change. The board's website is the authoritative source.

Key Formulas

Ohm's Law

V = I × R

Power

P = V × I

Power (resistance)

P = I² × R

Power (voltage)

P = V² / R

3-Phase Power

P = √3 × VL × IL × PF

Wye: Line V

VL = Vph × √3

Inductive React.

XL = 2πfL

Capacitive React.

Xc = 1 / (2πfC)

Impedance

Z = √(R²+X²)

Power Factor

PF = kW / kVA

Turns Ratio

V1/V2 = N1/N2

Voltage Drop

VD = 2×K×I×L / CM

NEC Conductor Protection (240.4D)

Wire Size	Max OCP (Cu)	Max OCP (Al)
#14 AWG	15A	—
#12 AWG	20A	15A
#10 AWG	30A	25A
#8 AWG	40A*	30A*
#6 AWG	55A*	40A*

* #8 and larger per ampacity tables 310.16–310.21

Motor OCP – Max Rating (Table 430.52)

Motor Type	Non-Time Delay Fuse	Inv. Time CB
Single-phase AC	300% FLC	250% FLC
3-phase squirrel cage	300% FLC	250% FLC
Wound-rotor	150% FLC	150% FLC
DC (constant speed)	150% FLC	150% FLC

Common NEC Articles

Article	Topic
100	Definitions
110	Requirements for Electrical Installations
200	Use and Identification of Grounded Conductors
210	Branch Circuits
215	Feeders
220	Branch Circuit, Feeder & Service Calculations
230	Services
240	Overcurrent Protection
250	Grounding and Bonding
300	Wiring Methods — General Requirements
310	Conductors for General Wiring
314	Outlet, Device, Pull & Junction Boxes
358	Electrical Metallic Tubing (EMT)
404	Switches
406	Receptacles, Cord Connectors & Attachment Plugs
408	Switchboards, Switchgear & Panelboards
410	Luminaires, Lampholders, Lamps
430	Motors, Motor Circuits & Controllers
440	Air Conditioning & Refrigeration
450	Transformers
480	Storage Batteries
500	Hazardous (Classified) Locations
517	Health Care Facilities
700	Emergency Systems
720	Circuits and Equipment Under 50 Volts

Key Numbers to Memorize

Value	What it means
3 VA/ft²	General lighting load — dwelling units (Table 220.12)
1,500 VA	Each small appliance circuit load (220.52A)
1,500 VA	Laundry circuit load (220.52B)
100%	Demand factor: first 3,000 VA of dwelling lighting
35%	Demand factor: next 117,000 VA of dwelling lighting
125%	Motor branch circuit conductor ampacity (430.22)
125%	Continuous load feeder/service sizing (215.2, 230.42)
360°	Max bends between pull points in conduit (358.26)
40%	Max conduit fill — 3+ conductors (Ch.9 Table 1)
5 mA	GFCI trip threshold
100A	Minimum dwelling service (230.79C)
6 ft	Max distance from any wall point to a receptacle (210.52A)
K=12.9	Resistivity constant for copper in VD formula
K=21.2	Resistivity constant for aluminum in VD formula

NEC Edition Timeline

The NEC is updated every 3 years. Each state adopts on its own schedule — many lag 1–2 editions behind. CE requirements for renewal often focus on changes in the newly adopted edition.

Edition	Key Changes / Highlights
NEC 2023	New Article 706 (Energy Storage Systems); expanded EV charging; 230V GFCI expansions
NEC 2020	GFCI expanded to 250V receptacles in basements; ground fault/arc fault expansions; updated PV/battery rules
NEC 2017	AFCI expanded beyond bedrooms to kitchens, laundry, hallways; PV rapid shutdown (690.12) expanded; GFCI expansions
NEC 2014	AFCI expanded to dormitories, hotel rooms; TR receptacles expanded; updated motor article
NEC 2011	Article 625 (EV charging) added; AFCI expanded to all dwelling bedrooms and living areas; updated grounding rules
NEC 2008	AFCI required in bedrooms; GFCI expanded; updated 250 grounding article
NEC 2005	Major reorganization of Article 250; updated service entrance rules
NEC 1999	AFCI first introduced (bedrooms only, 2002 effective); expanded GFCI locations

Typical CE requirement for license renewal: 24–120 hours per 3-year cycle (varies by state). Code update courses are accepted in most states.

Accounting Quick Reference

Term	Definition
Assets =	Liabilities + Owner's Equity
Gross Profit	Revenue − Cost of Goods Sold
Net Profit	Gross Profit − Overhead − Taxes
Markup 25%	Cost × 1.25 = Selling Price
Margin 25%	Profit ÷ Selling Price = 25%
A/R	Money customers owe you (asset)
A/P	Money you owe suppliers (liability)
WC Formula	Working Capital = Current Assets − Current Liabilities
SE Tax Rate	15.3% (SS + Medicare, both shares)
Section 179	Immediate expensing of qualifying equipment

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Electrician License Exam Prep