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. 

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.
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I recently was asked to review a series of emails from a colleague about equipment requirements for ready access or, as defined in Article 100 and used within text in the National Electrical Code (NEC), as “readily accessible.” This phrase is used to describe the location of circuit breakers, for ex

What does the National Electrical Code (NEC) require when installing isolated/insulated grounding-type receptacles and auxiliary grounding electrodes?

Most of Article 240 in the National Electrical Code (NEC) provides general requirements for overcurrent protection and overcurrent protective devices not more than 1,000 volts (V), nominal. As a general rule, the overcurrent device rating shall not exceed the ampacity of a conductor.

More on Codes & Standards

 
Installation of Nonmetallic Sheathed Cable, Exposed or in a Raceway
by Staff |

Is it acceptable to install nonmetallic sheathed cable (NM) exposed on a wall or in an attic, a basement, or a residential garage? Where would physical protection of the NM cable be required, and where is physical protection of NM cable often used but not necessarily required?

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Properly Installing Nonmetallic Cable-Part II
by Staff |

The number and the content of "Code Question of the Day" submissions concerning the installation of nonmetallic sheathed cable suggests vast differences among, or lack of proper inspection of, electrical installations using Type NM cable as the wiring method.

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Branch Circuit, Feeder, and Service Calculations, Motors and Their Circuits and More
by Staff |

CODE CITATIONS: Article 110-Requirements for Electrical Installations; Article 210-Branch Circuits; Article 220-Branch Circuit, Feeder, and Service Calculations; Article 230-Services; Article 250-Grounding; Article 310--Conductors for General Wiring; Article 430-Motors, Motor Circuits, and Controlle

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Using a Two-Pole Breaker to Feed Split-Wired Receptacles with Break-off Tabs

It seemed like a simple run-of-the-mill question when first presented. So, let's run it again. QUESTION: "If I split-wire a receptacle by breaking off the tab provided on the receptacle, do I have to use a two-pole breaker to feed this receptacle?" The answer is a qualified yes.

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Installing Lights in Clothes Closets
by Staff |

One of the most confusing aspects of residential wiring is installing lighting fixtures in clothes closets. Therefore, the National Electrical Code (NEC) devotes one of its relatively few diagrams (Figure 410-8) to the subject of where lighting fixtures can be located in clothes closets.

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Requirements for Electrical Installations
by Staff |

110-26 Spaces Surrounding Electrical Equipment

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