CEA Cheat Sheet 2026

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

1. What safety feature should testing equipment have? → Proper insulation and overload protection
2. An apprentice measures the opposition to current flow in a circuit. What is this property called, and what unit is it measured in? → Resistance, measured in Ohms (Ω)
3. What is the minimum size copper grounding electrode conductor required for a service with a 350 kcmil copper service entrance conductor? → #2 AWG
4. Which of the following materials is required for the side rails of a portable ladder being used by an apprentice near exposed energized electrical equipment? → Nonconductive material, like fiberglass
5. If an ideal transformer draws 5A at 240V on the primary, what is the secondary current when the secondary voltage is 120V? → 10A
6. Which tool is best for cutting electrical cables? → Cable cutters
7. Which instrument is used to test the integrity of a transformer's winding insulation? → Megohmmeter (megger)
8. In a wye-delta reduced-voltage starter, what is the motor connection at startup? → Wye (star)
9. What happens to a transformer's overall efficiency when it operates significantly below its rated KVA load? → Efficiency decreases because constant core losses become a larger fraction of output power
10. Which type of motor control device uses a bimetallic strip or melting alloy (solder pot) to sense motor overload? → Thermal overload relay
11. Which wiring method is commonly used in residential homes? → Non-metallic sheathed cable (NM cable)
12. What is the maximum number of conductors allowed in a standard electrical box? → Depends on box size and conductor gauge
13. Which conductor is NOT permitted to be used as a grounding electrode conductor? → Aluminum in direct contact with masonry or earth
14. What does a clamp meter measure? → Current by clamping around a conductor
15. Which type of fire extinguisher is appropriate for electrical fires? → Class C extinguisher
16. In a residential service panel, the neutral bar and the equipment grounding bar must be bonded together at which location? → Only at the main service panel
17. Which device protects people from electrical shock? → Ground Fault Circuit Interrupter (GFCI)
18. According to NEC Article 250, which conductor connects the grounded (neutral) conductor to the equipment grounding conductor at the service? → Main bonding jumper
19. What is the minimum burial depth for a ground rod electrode per the NEC? → 8 feet
20. What is the primary purpose of a magnetic motor starter? → To provide remote switching and overload protection for a motor
21. Which transformer type has its secondary winding electrically isolated from the primary winding with no common connection? → Isolation transformer
22. What is the purpose of a continuity tester? → To check if a circuit is complete
23. What is the primary purpose of an equipment grounding conductor (EGC)? → To provide a low-impedance path for fault current so overcurrent devices operate quickly
24. When installing Type NM cable in a new residential construction, which of the following is an NEC-compliant method for securing the cable? → Within 12 inches of a single-gang nonmetallic box and every 4.5 feet thereafter.
25. According to NEMA standards, what does a NEMA 12 enclosure protect against? → Dust, dirt, and dripping non-corrosive liquids for indoor use
26. In a series circuit, if one of three light bulbs burns out, what happens to the other two bulbs? → They all go out.
27. What is the National Electrical Code (NEC)? → A set of safety standards for electrical installations
28. Why should electrical tools be insulated? → To prevent electrical current from passing through the user
29. What is the primary difference between Alternating Current (AC) and Direct Current (DC)? → DC flows in one direction, while AC periodically changes direction.
30. The flow of electrons through a conductor is known as: → Current