NETA Journal's

Electrical Risk Hazard Analysis

Question: Why conduct a Risk Hazard Analysis (RHA) when working on or near live parts? Answer: When a risk hazard analysis is properly performed there is a substantially reduced chance of injury. Also, NFPA 70E orders you to perform the analysis. For the purpose of this article, there are two types of Risk Hazard Analysis:

Testing of Electrical Power System Components: What Factors Determine How Much and How Often?

Almost all modern (and not so modern) electrical power systems have the same issue: how often should I test the critical components to assure continued serviceability and/or to assess remaining service life?

Medium-Voltage Circuit Breaker Timing-Test Evaluations Part I

With today’s computer technology capabilities, the use of statistical tools to evaluate test data is just a mouse click away. This paper presents a new way to evaluate circuit breaker timing test results. It provides methods for comparing test measurements, validating test data, and determining acceptability of breaker performance.

What's Wrong with this Picture?

You are to filter the oil on a 13.2 kV primary transformer. After starting the work the following photo is taken of the high side section. What’s wrong with this picture?

News that’s NETA

NETA's Board of Directors smiled for the camera in the midst of the activity at PowerTest 2007.

Circuit Breaker Lubrication in the Field


There have been many circuit breaker failures attributed to lack of lubrication or improper lubrication. Many of these failures have lead to arc-flash incidents that have damaged equipment or injured personnel. 

What's Wrong With This Picture

You walk up to a padmount transformer that was connected by others, and notice the following conditions.

Taking Lockout Too Far

Until recently I didn't think you could take a lockout program too far. How wrong I was! On a recent trip to Indonesia I met an electrical engineer who told me a story about a medium-voltage equipment failure that occurred during a normal lockout procedure.

Tech Quiz #80 - Low Voltage Power Circuit Breakers

Low-voltage power circuit breakers are virtually everywhere. These devices are a critical part of the protective system but are often overlooked and much abused. Even though they are so critical, many equipment owners know almost nothing about them. How much do you know?

Corona Imaging — See the Invisible

It felt like a fine spring morning in eastern Oregon as my colleague and I rolled up the power plant driveway, although the date on my Blackberry indicated mid-February. After some friendly greetings and hand-shaking with maintenance personnel, we signed in at the control room and viewed the not too lengthy or boring safety video.

Step and Touch Potentials

For theoretical considerations, "true earth" can be viewed as a conductor deep in the ground, one with virtually no resistance. With this understanding,
ground resistance can be thought of as the resistance between, say, a ground mat or substation grid and true earth.

OSHA Releases New Subpart S

The Occupational Safety and Health Administration (OSHA) has released a new Subpart S (Part II) of the 29 CFR Part 1910, Electrical Standard General Industry Electrical Installation regulation as a Federal Register dated February 14, 2007. This document will become federal law effective August 13, 2007 (see Figure 1).

ATS07 to Begin Process of Becoming ANSI Standard

The need for acceptance testing of electrical power systems is very clear to those with extensive startup and/or operating experience. Shipping and installation damage, field and factory wiring errors, manufacturing defects, and systems and components not in accordance with drawings and specifications are some of the many problems that can be detected by appropriate testing.

New Techniques for Dynamic Relay Testing

In part 1, the following four problem areas experienced by utilities that have tried dynamic relay testing were presented.

Testing for Corrosive Sulfur Effects

Over the past several years there have been a number of failures of power transformers and reactors where there are indicators of copper corrosion and formation of copper sulfides on conductors and insulating materials.

Interchangeability of Drawout Circuit Breakers in Switchgear Assemblies

One of the key features of switchgear assemblies using drawout circuit breakers is the interchangeability of circuit breakers within an assembly.

Critical Maintenance for Circuit Breakers

Circuit breakers aren't much fun. They don't do a whole lot; just open contacts and close contacts. Pretty boring. However, if a breaker doesn't operate when it's supposed to, life can get very exciting!

World Class Maintenance

As maintenance departments have become major cost centers within industrial plant organizations, more management attention is being applied to reducing maintenance costs while maintaining operability and reliability.

Methods of Inspection to Determine the Presence of Potential Arc-Flash Incidents

Arc flash can kill. Arc flash can be considered as a short circuit through the air. It produces tremendous energy that will travel outward from
electrical equipment.

Overcurrent Definitions

There are several terms that we use to name abnormal current in an electric power system. Although these terms are sometimes used interchangeably,
they really aren't interchangeable.

The Future of Predictive Technologies is Here Now

In today's competitive environment, it is imperative to capitalize on advances in technology that allow new approaches to the maintenance of a facility's physical assets. These include reliability-centered maintenance, predictive diagnostics, condition monitoring, and expert systems.

Tech Quiz #79 - Fuses

Which of the following fuse types is not current-limiting? A. Fuse class J B. Fuse class RK-5

New NETA Staff Members

Andrea Allen has joined the NETA team as our Creative and Communications Manager.

Maintenance and Testing of Battery Systems

The electrical maintenance and testing requirements for utility, industrial and large commercial facilities vary significantly depending on the electrical
infrastructure of the facility.

Transformer Testing — Are You Missing the Test Point?

It is common knowledge that transformer cost comprises anywhere from 40- 60 percent of the price of a substation. The cost has spiraled out of control, up 40 percent from last year.