More documentation is being required in the National Electrical Code and NFPA 70E, the Standard for Electrical Safety in the Workplace. The words “documented” or “documentation” appear in the 2017 NEC approximately 104 times...
Jim Dollard has an extensive background in codes and standards. Send questions about the National Electrical Code (NEC) to Jim at codefaqs@gmail.com. Answers are based on the 2020 NEC. Getting started with the NEC I’m a...
The National Electrical Code has several requirements applicable to emergency systems, legally required standby systems, essential electrical systems and optional standby systems. From a basic performance standpoint, the...
Arc energy reduction is critical for working on high-energy electrical equipment. However, many electrical designers, contractors and inspectors don’t understand the issues surrounding energy reduction. Arc energy reduction...
For the first time in 34 years, I am participating in the National Electrical Code process as an active submitter of public input. For most of my career, I was unable to submit input or comments because my role was to remain...
Sometime between the 1925 and 1933 National Electrical Codes , the maximum number of service disconnects changed from one or two disconnects to a maximum of six. I cannot verify the exact edition where the change occurred. I...
The National Electrical Code adoption process is continuously active. Jurisdictions that adopt and use the latest edition of the NEC have the benefits of a Code that has been developed and maintained by qualified technical...
Jim Dollard has an extensive background in codes and standards. Send questions about the National Electrical Code (NEC) to Jim at codefaqs@gmail.com. Answers are based on the 2020 NEC. Psychiatrist’s office as patient care...
Futuristic smart cities have been envisioned for years. TV shows from the last century predicted amazing technological leaps. “Lost in Space,” an early 1960s sci-fi show, forecast interplanetary travel in 1997. It also...
Jim Dollard has an extensive background in codes and standards. Send questions about the National Electrical Code (NEC) to Jim at codefaqs@gmail.com. Answers are based on the 2020 NEC. Doors swings Why doesn’t 110.26 require...
New Section 680.4 in Article 680 in the 2020 National Electrical Code enables the authority having jurisdiction (AHJ) to require periodic inspection and testing of swimming pools, fountains and similar installations such as...
When I was first involved with the NEC , there were several ad hoc subcommittees. Some were assigned a very specific task to meet over lunch or in the evenings during a committee meeting. Others met between the panel meetings...
A friend called me recently with some intriguing questions about some electrical work that he was having done at his newly purchased home. The home was built in the mid-to-late 1950s with some electrical work done in various...
Recently, I was asked to explain the reason for the ferrous metal raceway bonding requirements in 250.64(E). Although the National Electrical Code never uses the term “choke effect,” many in the business understand its...
To understand the purpose of ground-detection equipment installed for ungrounded systems, it is best to have a fundamental understanding of ungrounded system performance and the rules that apply to them. Section 250.4(B)...
In the late 1950s and early 1960s, Kodak, then the largest manufacturer of film and cameras, began a product promotion with a series of Christmas-themed advertisements with the tagline “Open me first.” The ad encouraged...
While researching grounding and power quality, the information was divided between how to design the grounding systems of an electrical infrastructure that was optimized to maximize the quality of the electrical power, and...
July’s article provided a preliminary discussion on cathodic action and dissimilar metal reaction with deterioration of various metals, such as steel water and gas lines. Many of the old metal underground natural gas lines...
Cathodic action and dissimilar metal interaction are phenomena with a long history of recognition in the laws of physics as well as within the National Electrical Code. I first ran across this issue back in the 1970s and ‘80s...
Jim Dollard has an extensive background in codes and standards. Send questions about the National Electrical Code (NEC) to Jim at codefaqs@gmail.com. Answers are based on the 2020 NEC . NEC arrangement Why are swimming pools...
