National Electrical Code Articles and Information

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 Codebookcity.com. 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, what’s the rule on ampacity?
    

5. If feeder conductors are supplying transformer loads and utilization equipment, what’s 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?