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National Electrical Code Articles and Information

NEC Quiz: Article 215

by Mark Lamendola

Quiz Questions

Code Quiz: Article 215

Based on the 2005 NEC

Questions and answers written by Mark Lamendola, who has worked as a master electrician, electrical inspector, and design engineer. Mark is an IEEE Senior Member, and the Code article author for Since 1996, he has been writing National Electrical Code articles for electrical trade magazines and has an extensive portfolio of hundreds of NEC articles..

  1.  When sizing feeders of not more than 600V, you must ensure they have an ampacity not less than that required to supply the load. But, you must calculate that load based on three Parts of an Article. Which Article is that?

  2. You must choose a feeder conductor circuit size that has a minimum allowable ampacity of not less than 125% of the noncontinuous load plus 125% of the continuous load, but before applying what?

  3. Under what conditions must you ensure your feeder conductor ampacity is not less than that of your service conductors?

  4.  If feeder conductors are supplying just transformer loads, whatís the rule on ampacity?

  5. If feeder conductors are supplying transformer loads and utilization equipment, whatís the rule on ampacity?

  6. Which Article provides the requirements for feeder protection?

  7. True or false: It is illegal for feeders to share a common neutral.

  8. What provision must you make, if you are going to use an autotransformer to supply a feeder?

  9. Where do you find the requirements for identifying the grounded conductor and the equipment grounding conductor of a feeder?
  10. If your premises has a mix of voltages supplying your feeders (e.g., 480V and 4160V), what requirements must you meet?

Answers to this quiz are here: Answers to this quiz

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How the NEC is arranged

  1. The first four Chapters of the NEC apply to all installations.
  2. Article 90 precedes Chapter One, and establishes the authority of the NEC.
  3. Article 80 follows the body of the NEC; it exists as Annex H. It provides the requirements for administration.
  4. Chapters 5, 6, and 7 are the "special" chapters, covering special: occupancies, equipment, and conditions (in that order).
  5. Chapter 8 provides the requirements for communications systems.
  6. Chapter 9 provides tables.
  7. The appendices provide mostly reference information.
  8. Appendix D contains examples that every NEC user should study.

Try your NEC moxy:

  • Do you know the difference between bonding and grounding? Hint: Look in the NEC, Article 100.
  • Does the NEC refer to grounding incorrectly in any of its articles? Yes! So be careful to apply the Article 100 definitions. Don't ground where you should bond.
  • When doing motor load calculations, which Article covers hermetic motors? Answer: While Article 440 covers the application of hermetic motors, it does so only by amending Article 430 because hermetic motors are a special case of motors. For motor load calculations, refer to Article 430.
  • Does the NEC provide a voltage drop requirement? Yes! It does so in a special case, which is Article 648 Sensitive Electronic Equipment. But for general applications, it does not provide a requirement; it merely provides a recommendation in a couple of FPNs.
  • Take our Code Quizzes.

Remember other applicable codes, rules, standards, and references:

  • OSHA's electrical worker safety rules.
  • IEEE standards.
  • NETA standards.
  • NFPA standards.
  • International Codes (if applicable to the installation).
  • State Codes (if the state has them).
  • Local ordinances and permit requirements.
  • Local fire codes.
  • Manufacturer requirements or guidelines.
  • Customer security requirements.
  • Industry standards.
  • Your company's own internal standards, practices, and procedures.
  • Engineering drawing notes.



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