Reduced-Voltage Autotransformer Starter Performance Misunderstood
Dec 1, 1998, By EC&M Staff
The author of the article “Reduced-Voltage Starters: Choosing The Best Type For Your Application” (June 1998 issue) made an error with the following excerpt,...
Unconventional Transformer Connections — Part 2
Dec 1, 1998, By Scott Falke, Turlock, Calif.
Part 1 showed us how to use unconventional transformer configurations to resolve equipment availability problems and unusual circumstances. Part 2 provides more examples, and a look at the tradeoffs involved. Let's begin with Case Five....
Who’s Right?
Nov 1, 1998, Edited by Robert J. Lawrie
Q. At my facility, we have several 4160V asynchronous motor applications. A situation arose where a grinding line would blow fuses when anyone tried to...
The Updated IEEE Emerald Book: An Advanced Peek
Nov 1, 1998, By Ken Michaels, F.D. Hayes Electric Co.
Here are five key revisions to this IEEE standard, some of which are in response to manufacturer and end user concerns. The upcoming version demonstrates that its working group is able to stay current in the ever-changing power quality field....
Threat of Litigation Causes Consultants to Decline Work
Nov 1, 1998, By EC&M Staff
The threat of litigation and frivolous lawsuits continue to be a primary concern for consulting engineering firms, according to the 1997-1998 Professional...
Be Smarter Through Standards
Nov 1, 1998, By Mark Lamendola, Technical Editor
"Column this for is opinion editors of." Did this sentence make sense to you? It is confusing because I didn't follow the standards involved in making...
Industry Experts Question EMF Working Group Report
Oct 1, 1998, By EC&M Staff
A working group, put together by the National Institute of Environmental Health Sciences (NIEHS), judged (by a vote of 19 to 9) that the International...
Some Motors Have Design B LR Limits But Meet Design E Efficiency Levels
Oct 1, 1998, By EC&M Staff
Thanks for Robert Lawrie’s article, “Watch Out For Burnouts On Hard-To-Start Loads,” in the March issue. With continuous change and increased efficiency,...
What’s the Most Cost-Effective Way to Obtain 380V?
Oct 1, 1998, Edited by Robert J. Lawrie
Q. A large textile plant purchased several looms from Europe, which operate on 380V, 3-phase. The only distribution voltage available is 480V, 3-phase....
Diodes or SCRs? It's Either Or
Oct 1, 1998, By EC&M Staff
While reading Cory Lamerande’s article on harmonic distortion (March issue), I found a contradiction. The text under Figure 5, on page 74, (reproduced...
Unconventional Transformer Connections — Part 1
Oct 1, 1998, By Scott Falke
Sometimes, budget constraints keep you from buying a new transformer for a specific application. You already have a boneyard of transformers; can you make do with what you have? In many cases, the answer is yes....
Data And Power Wiring: Similarities & Differences
Oct 1, 1998, By Paul Rosenberg, Consulting Editor
The industry is instinctually familiar with power wiring. Now, it's time for electrical contractors to learn as much about data wiring as they already know about power wiring....
Superconducting Transformer (HTS) Successfully Tested
Aug 1, 1998, By EC&M Staff
Is this experimental unit the most powerful superconducting transformer constructed to date? It’s already bringing sweeping changes to transformer and substation design....
Quick Disconnects Speed Motor Changeouts
Jul 1, 1998, By Jerry Woodward, Thomas & Betts Corp.
Unique device has contact rings with high conductivity and high contact force....
Turning The Tables On Shaft Voltage And Bearing Currents
Jun 1, 1998, By David W. Schlegel, Russel J. Kerkman, and Gary L. Skibinski
High bearing current concentrations can damage bearing raceways. This damage can degrade bearing performance and even shorten motor life....
