An increasing number of occupancy sensor switches, involving infrared sensing, are being installed in commercial, residential and industrial installations to cut power usage and comply with energy conservation codes.
If you have a National Electrical Code (NEC)-related problem, are experiencing difficulty in understanding a Code requirement, or are wondering why or if such a requirement exists, ask Charlie, and he will let the Code decide. Questions can be sent to firstname.lastname@example.org.
If you have a National Electrical Code (NEC)-related problem, are experiencing difficulty in understanding an NEC requirement, or are wondering why or if such a requirement exists, ask Charlie, and he will let the Code decide. Send your questions to email@example.com.
The first edition of the National Electrical Code (NEC) was developed in 1897. Including the 2008 edition, there are 51 editions. A lot has changed, both in the electrical industry and in the Code book, since the first edition.
Expanding electrical systems for existing residential, commercial and industrial facilities can be an expensive and difficult endeavor, unless the electrician, electrical contractor or design engineer can apply an optional calculation rule in Part IV of Article 220.
Lately, I’ve received a number of inquiries from contractors concerning the installation of lightning protection systems. Those electrical contractors’ main concerns are how to begin to design and install such a protective system and who or what entity requires or regulates its installation.
A recent addition to the 2008 National Electrical Code (NEC) has prompted a possible change for the 2011 NEC and a number of questions from electricians, electrical contractors, electrical inspectors and electrical engineers.
If you have a Code-related problem or are experiencing difficulty in understanding a National Electrical Code (NEC) requirement and are wondering why or if such a requirement exists, ask Charlie. And we will let the Code decide.
Article 220 of the National Electrical Code (NEC) provides requirements for calculating branch-circuit, service and feeder loads. Definitions for the three types of loads that Article 220 covers are in Article 100.
National Fire protection Association (NFPA) 70B (Recommended Practice for Electrical Equipment Maintenance) contains the requirements to perform frequency inspections and evaluate components of equipment for safe operation.
George W Flach wrote the Code Q&A column For roughly 40 years; regular readers are likely used to a certain format and style could not and did not wish to replicate. He was truly one-of-a-kind. That said, we want to maintain an outlet for all your National Electrical Code (NEC) questions.
The National Electrical Code (NEC) contains an introduction, nine chapters and eight annexes; Article 90 is the introduction to the NEC, and it includes specifications that are essential to the rest of the Code book. The scope is one item covered in the introduction (in 90.2).
In November, I covered the layout of National Fire Protection Association (NFPA) 70, the National Electrical Code. Here, I discuss the layout and use of NFPA 70E and its relationship to NFPA 70.