E2 Study Guide 2026

Everything you need to pass the E2 exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.

📋 E2 Exam Format at a Glance

Questions

210 min

Time Limit

75.00%

Passing Score

Take a Full E2 Exam Simulation →

📚 E2 Topics to Study (88)

Commercial Service Load Calculations · 7 cards Commercial Service Load Calculations · 7 cards Commercial Service Load Calculations · 7 cards Commercial Service Load Calculations · 7 cards Conductor Ampacity and Derating · 7 cards Conductor Ampacity and Derating · 7 cards Conductor Ampacity and Derating · 7 cards Conductor Ampacity and Derating · 7 cards Emergency and Standby Systems · 7 cards Emergency and Standby Systems · 7 cards Emergency and Standby Systems · 7 cards Emergency and Standby Systems · 7 cards General Requirements and NEC · 7 cards General Requirements and NEC · 7 cards General Requirements and NEC · 7 cards General Requirements and NEC · 7 cards Grounding and Bonding · 7 cards Grounding and Bonding · 7 cards Grounding and Bonding · 7 cards Grounding and Bonding · 7 cards Hazardous (Classified) Locations · 7 cards Hazardous (Classified) Locations · 7 cards Hazardous (Classified) Locations · 7 cards Hazardous (Classified) Locations · 7 cards Health Care Facilities · 7 cards Health Care Facilities · 7 cards Health Care Facilities · 7 cards Health Care Facilities · 7 cards Motors and Transformers · 7 cards Motors and Transformers · 7 cards

See all 88 topics as flashcards →

✍️ Sample E2 Questions & Answers

1. A transformer nameplate lists an impedance of 5.75%. This value is primarily used to calculate:

✓ Available fault current

Transformer impedance (%Z) is the key parameter for calculating available short-circuit current on the secondary side.

2. Per NEC 312.11, when shall a wiring enclosure (cabinet or cutout box) be secured to the wall or other supporting surface?

✓ It shall be securely fastened in place

NEC 312.11 requires that all cabinets, cutout boxes, and meter socket enclosures be securely fastened in place.

3. A run of rigid PVC conduit passes through a building expansion joint. The inspector should verify the presence of:

✓ An expansion coupling listed for the purpose

NEC 352.44 requires an expansion fitting listed for PVC where the conduit crosses a structural expansion joint.

4. When installing an isolated power system, the maximum total length of the branch circuit conductors on the secondary side of the isolation transformer is:

✓ 50 feet

NEC 517.160(A)(3) limits the length of secondary conductors of an isolated power system to 50 feet to minimize distributed capacitance that degrades isolation.

5. When sizing conductors for a feeder supplying several motors, NEC 430.24 requires the feeder ampacity to equal the largest motor FLC multiplied by 125% plus:

✓ The sum of the remaining motor FLCs at 100%

NEC 430.24 adds 125% of the largest motor FLC to the sum of all other motor full-load currents at 100%.

6. In a Class I, Zone 0 location per NEC Article 505, flammable concentrations of gases are present:

✓ Continuously or for long periods under normal conditions

Zone 0 is the most hazardous classification under the Zone system, where flammable concentrations are present continuously or for long periods.

🎯 Free E2 Practice Tests

General Requirements and NEC · 7 questions Hazardous (Classified) Locations · 7 questions Hazardous (Classified) Locations · 7 questions Plan Review and Inspections · 7 questions Safety Standards and Practices · 7 questions Sizing and Protection of Motor Circuits · 7 questions Sizing and Protection of Motor Circuits · 7 questions Systems and Equipment · 7 questions Systems and Equipment · 7 questions General Requirements and NEC · 7 questions

📖 E2 Guides & Articles

Your E2 Study Path

1. Learn with Flashcards → 2. Drill Practice Tests → 3. Take the Full Exam Simulation

🃏 E2 Flashcards (595)🏆 E2 Exam Simulation

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