It doesn’t take an electrician or engineer to know that lightning is a major cause of electrical interference and damage. Protecting the electrical system against such a danger is paramount. A lightning stroke can be hotter than the surface of the sun, with voltage estimated as high as 120 million volts, including 400 kA and 500 megajoules of energy. Utility …
Electrical Service Work and Worker Fatigue: Take Care of Yourself!
Chances are you are in an electrical career you love: Testing, maintaining, installing, commissioning, designing, rebuilding, engineering, improving…and generally making electrical power systems safer and better. But are you doing so with a focus on managing the possible onset of acute or chronic fatigue? We live in a busy world — do more with less; be efficient in your tasks; …
NFPA 70E — 2021 Edition: Second Draft Meeting Highlights and Summary
The second draft technical committee meeting for the 2021 Edition of NFPA 70E was held July 15–19, 2019 in Indianapolis, Indiana. The public comments submitted for committee action following the first draft meeting were discussed and voted on. NETA was represented at the meeting and participated in the actions. To remind everyone of the NFPA process for changes to a …
NETA World Keeps You One Step Ahead of Emerging Technology
Emerging technologies continually alter the way electrical testing is performed in the field. New technology can vary from more efficient ways to perform long-standing test routines to introducing a new test technology and just about everything in between. This issue’s authors share their knowledge of recent developments in the field of electrical testing. Fall is typically one of the busiest …
Using Measurement Results to Diagnose the Condition of High-Voltage Rotating Machines —Part 2
Diagnosing the condition of complex systems such as high-voltage rotating machines has never been a simple task. Design requirements, the use of different materials, and demanding operating conditions require multiple off-line tests and on-line monitors to provide information on the machine’s condition. Part 1 of this article described the application of various off-line test techniques to assess stator and rotor …
Progress in Transformer Dissolved-Gas Analysis
Dissolved-gas analysis started out many years ago as a quick and simple test: Someone in the substation would briefly open a valve and sniff the transformer’s head-space gas. The pungent odor of a trace of acetylene would signify a potentially serious problem. By the late 1960s, it was possible to use a gas chromatograph as a much more sensitive nose …
What’s in a Partial Discharge Monitoring System?
Partial discharge (PD) testing is becoming common in U.S. industrial systems and is gaining acceptability in U.S. utilities. Testing in the form of periodic surveys can provide valuable insight into asset condition. Beyond periodic surveys, full-time system monitoring is the state of the art in PD detection, offering additional capabilities that: Warn of rapidly evolving PD situations that might go …
Unlocking the Mysteries of Narrow Band DFR
Southern California Edison (SCE) began using primary to secondary winding (CHL) narrow band dielectric frequency response (NBDFR) measurements for condition assessment of used distribution class transformers in 2015; 1800 units are evaluated annually. NBDFR is a series of insulation power factor measurements taken from 1–400 hertz, usually at a low voltage. The data derived from the series of CHL measurements …
High-Voltage Arc Flash Assessment and Applications—Part 2
Part 1 of this article, which was the cover story in the previous issue of NETA World, explored the need for high-voltage arc flash (HVAF) assessment to protect utility workers who are exposed to voltages above 15kV. It also compared various methods to calculate the incident energy from HV and MV electric arcs. Analyzing the results demonstrated that several methods …
A Tribute to John Moore 1942-2019
I met John Moore in 1975 at an IEEE meeting in San Francisco. He had started Electro-test, Inc. (ETI) in his garage just four years earlier. I was fascinated by his enthusiasm and passion for his business. I was working at a large corporation then, and at the time, I didn’t even understand why such a service was needed; the …