Codes & Standards

 

Essential to the work of the electrical contractor is knowledge of the National Electrical Code, the National Electrical Installation Standards and additional standards and codes administered by the National Fire Protection Association, the Occupational Safety and Health Administration and others. Here is a list of all our articles on codes and standards listed chronologically by issue date. 

The National Electrical Code (NEC) has contained multiwire branch-­circuit color coding since the early 1950s. However, it wasn’t until the 2005 NEC that it required the voltage system to identify ungrounded conductors where a building had more than one voltage system.

The stated purpose of the National Electrical Code (NEC) is the practical safeguarding of people and property from hazards arising from electricity use. One way to help do this is to ensure there is enough room around electrical equipment.


This article reviews changes in Chapter 3, Wiring and Methods and Materials, and Chapter 4, Equipment for General Use, in the 2017 edition of the National Electrical Code (NEC).
 336.10 Uses Permitted


What is a knife switch?


Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC), Jim will help you solve it. Questions can be sent to codefaqs@gmail.com. Answers are based on the 2014 NEC.
 What is a knife switch?


More on Codes & Standards

 
Mission Critical

A new article has been proposed for the 2008 National Electrical Code (NEC) covering mission-critical electrical systems installed in vital infrastructures or facilities where, if the infrastructure or facility was either destroyed or incapacitated, disruption of the facility would affect national


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AC and MC Bushings, Outdoor Receptacles and More

AC and MC bushings Q: Sections 320.17 and 330.17 indicate that Types AC and MC cables must be installed in accordance with 300.4, which includes protection of the cables by listed bushings or listed grommets that cover all metal edges of metal studs.


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Pull- and Junction-Box Calculations, Part VIII

314.28 Pull and Junction Boxes Requirements pertaining to the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes are in Article 314 of the National Electrical Code (NEC).


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Only Temporary

Recent discussions on ground-fault circuit interrupter (GFCI) protection for personnel on construction sites have indicated that there seems to be a misunderstanding of whether generator power is excluded from the GFCI requirement.


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Transformer Sizes, Metal Clad Cables and More

Outside feeder grounding and bonding Q: What grounding and bonding requirements apply to an outside feeder that supplies a woodworking hobby shop that is located in a detached building and is about 60 feet from, and supplied from, a single-family residence?


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Pull- and Junction-Box Calculations, Part VII

314.28 Pull and Junction Boxes Chapter 3 of the National Electrical Code (NEC) covers wiring methods and materials. Article 314 covers the installation and use of all boxes and conduit bodies used as outlet, device, junction or pull boxes, depending on their use.


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Now Hear This

Within the past few years, many of us have installed surround sound systems in homes and business. What seems to be lacking is an understanding of the new requirements that have been incorporated into the totally revised Article 640 in the National Electrical Code (NEC).


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