Sulfur Hexafluoride Gas Hazards

Paul Chamberlain, American Electrical Testing Co., LLC Columns, Safety Corner, Spring 2019 Columns

Sulfur hexafluoride, also known as SF6 gas, is a commonly used and excellent insulator found in many medium to large circuit breakers protecting transmission and distribution equipment. It has been argued that gas-filled breakers are superior to those filled with oil, air, or a vacuum. They operate cooler and with no noise or gas emissions and are considered relatively low …

Sulphur Hexafluoride Circuit Breakers

James R. White, Shermco Industries Columns, Spring 2019 Columns, Tech Quiz

Sulphur hexafluoride circuit breakers used to be the domain of utilities, but they are liable to be used now by any large- or medium-size industrial. This Tech Quiz will review some of the NETA standard requirements for these circuit breakers. 1. In ANSI/NETA ATS, which ANSI/IEEE standard is referred to if manufacturer’s data is not available? a. C57.04 b. C57.11 …

Computer-Based Technology for Ground Testing

Jeffrey R. Jowett, Megger Columns, Spring 2019 Columns, Tech Tips

Since its inception in the early 20th century, testing grounded electrodes has been grounded on one technique and technology only: Fall of Potential. The test instrument made contact with the earth through long leads and driven probes, injected a current between the electrode being tested and a remote probe, and measured the voltage drop caused by earth resistance to another …

Testing Battery Banks

Ron Widup and James (Jim) R. White Columns, NFPA 70E and NETA, Spring 2019 Columns

The 2021 NFPA 70E cycle started last year, and the Second Draft Meeting will convene July 14–19, 2019. One interesting benefit of being on the committee is the information that is shared with us. Some of it is obviously presented to serve one purpose or another, but some of it is put forward by well-known, independent laboratories that have no …

SF6—The Alternative Gas

Danielle White and Lina Encinias Features, Spring 2019 Features

With the ever-growing challenges of federal and local reporting and SF6 emission reduction, several alternatives have been presented to the industry as replacements for SF6 gas. As the industry continues to review and consider alternatives, we should not limit our solutions, and the alternative of turning to the existing stockpile of SF6 gas offers several benefits. However, what preventative measures …

Circuit Breaker and Transducer: Where Do I Connect?

Robert Foster Cover Story, Spring 2019 Cover Story

Many types of equipment in the electrical transmission and distribution network perform a specific and necessary operation, and the circuit breaker is no exception, as it serves to protect the substation’s valuable assets. The circuit breaker — defined as a mechanical switching device — is unique: At one time, it must function as a nearly perfect conductor; at another time, …