Licensed Electrical Contractor Cheat Sheet 2026

The 30 highest-yield Licensed Electrical Contractor facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. According to NEC 250.122, how is the minimum size of an equipment grounding conductor determined for a branch circuit? → By the rating of the overcurrent device protecting the circuit
2. When should you replace a circuit breaker? → When they fail to reset or show damage.
3. Which of the following best defines a 'Readily Accessible' location according to NEC Article 100? → Capable of being reached quickly without climbing over or removing obstacles.
4. What is the primary purpose of a mechanics lien in the electrical contracting business? → To secure payment for labor and materials provided on a construction project
5. Which NFPA standard is commonly known as the National Electrical Safety Code (NESC) and covers utility installations? → NFPA 70 does not cover utilities; the NESC is IEEE C2
6. Which type of electrical current periodically reverses direction? → Alternating current (AC)
7. What is the maximum penalty per violation that OSHA can impose on an electrical contractor for a willful safety violation as of current federal guidelines? → $161,323
8. What should be used to protect circuits from overloads? → Circuit breakers or fuses.
9. What is the total impedance of a series RLC circuit with R = 30 ohms, XL = 50 ohms, and XC = 10 ohms? → 50 ohms
10. For a parallel conductor installation using two sets of 500 kcmil conductors per phase, what is the NEC requirement for conductor arrangement? → Each phase must have the same length, type, and termination method
11. The NEC requires GFCI protection for 125V, 15- and 20-amp receptacles in: → Bathrooms, kitchens within 6 feet of sink, and outdoors
12. What does the term 'scope of work' define in an electrical contracting agreement? → The specific tasks, deliverables, and boundaries of the contracted work
13. What is the minimum rating required for any branch circuit that supplies two or more outlets or receptacles per NEC 210.3? → 15 amperes
14. What is the purpose of a transformer in an electrical circuit? → To change the voltage level in an AC circuit.
15. When troubleshooting a motor that hums but does not start, which component should be checked first? → Start capacitor
16. What is the primary purpose of equipment bonding jumpers in an electrical system? → To ensure electrical continuity and conductivity between metal parts
17. What is the function of a grounding electrode in an electrical system? → To safely discharge fault current into the earth.
18. Which of the following wiring methods is NOT permitted in a commercial garage as defined by NEC Article 511? → Type NM cable
19. How often should electrical maintenance be performed on commercial systems? → At least once a year.
20. A 14 AWG copper conductor on a 15-ampere branch circuit can safely supply a maximum continuous load of how many amperes? → 12 amperes
21. Under OSHA 29 CFR 1926.416, which of the following is a required safety practice when working near overhead power lines on a construction site? → All equipment must maintain at least 10 feet of clearance from lines up to 50 kV
22. Per NEC 110.26(C)(1), for equipment rated 1200 amps or more and over 6 feet wide, how many entrances to the required working space are needed? → Two entrances, one at each end of the working space
23. A 240V, single-phase branch circuit supplies three 1,200W baseboard heaters. What minimum branch circuit rating is required when treated as a continuous load? → 25 amperes
24. What is the minimum required height for overhead service conductors crossing a commercial parking lot subject to truck traffic? → 18 feet
25. Which document is typically required before an electrical contractor can legally begin work on a commercial project? → A building permit from the local authority having jurisdiction
26. In a wye-delta motor starter, what is the primary advantage of starting the motor in the wye configuration? → Starting current is reduced to approximately one-third of delta starting current
27. Per NEC 334.80, what is the maximum ambient temperature rating for standard Type NM cable? → 90°C
28. According to NEC 430.32, what is the maximum continuous motor overload protection setting for a motor with a marked service factor of 1.15 or greater? → 125% of nameplate FLA
29. The NEC requires a minimum of how many 20-amp small appliance circuits in a kitchen? → 2
30. When performing a standard load calculation for a single-family dwelling per NEC Article 220, what is the general lighting load allowance per square foot? → 3 VA per square foot