Letters: Reader Feedback

Electrical addendum Editor's note: This past year, CSE has reissued George Farrell and Frank Valvoda's classic "Art of Protecting Electrical Systems" series in our monthly electrical e-newsletter, archived in the electrical community at csemag.com. In the March Editor's Viewpoint, it was noted that Mr.


Electrical addendum

I greatly enjoyed reading the "The Art of Protecting Electrical Systems, Part 6" by By George Farrell and Frank Valvoda. I've been involved with short-circuit and withstand testing of fire pump controllers for some time and am glad to see a cogent and well thought out article on these topics. I particularly noticed the "selective protective devices" subheading. It may be interesting to note that 2005 Edition of NFPA 70 requires selective coordination of overcurrent protective devices used in emergency power systems. See Articles 700.27 and 701.18. There is significant confusion and controversy over these two new clauses.


Sea change here

Thank you once more for your straightforward and correct cautionary editorial ("Are we Overbuilt?" CSE 5/06, p.7 ). My sources tell me that construction costs are going up at 1.5% per month and that condo sales are bombing. Many cagey developers are selling buildings to institutions—who want the revenue stream—and placing their money only in very certain projects. They can do this because it is cheaper to buy a reasonably good building than to build a comparable new one. Thank you once again for your integrity.


Fan/VFD start-up issues

Under normal, across-the-line applications, this would be true. Because VFDs provide a soft-start feature—ramping up the motor slowly—the soft start eliminates the mechanical shock, stress and noise associated with across-the-line starting. The time between alternation no longer becomes as important.

Have something to say?

Send your comments to:

"Letters to the Editor" c/o Jim Crockett Consulting-Specifying Engineer 2000 Clearwater Drive Oak Brook, IL 60523 or E-mail:jcrockett@reedbusiness.com

No comments
Consulting-Specifying Engineer's Product of the Year (POY) contest is the premier award for new products in the HVAC, fire, electrical, and...
Consulting-Specifying Engineer magazine is dedicated to encouraging and recognizing the most talented young individuals...
The MEP Giants program lists the top mechanical, electrical, plumbing, and fire protection engineering firms in the United States.
Commissioning lighting control systems; 2016 Commissioning Giants; Design high-efficiency hot water systems for hospitals; Evaluating condensation and condensate
Solving HVAC challenges; Thermal comfort criteria; Liquid-immersion cooling; Specifying VRF systems; 2016 Product of the Year winners
MEP Giants; MEP Annual Report; Mergers and acquisitions; Passive, active fire protection; LED retrofits; HVAC energy efficiency
Driving motor efficiency; Preventing Arc Flash in mission critical facilities; Integrating alternative power and existing electrical systems
Putting COPS into context; Designing medium-voltage electrical systems; Planning and designing resilient, efficient data centers; The nine steps of designing generator fuel systems
Designing generator systems; Using online commissioning tools; Selective coordination best practices
As brand protection manager for Eaton’s Electrical Sector, Tom Grace oversees counterfeit awareness...
Amara Rozgus is chief editor and content manager of Consulting-Specifier Engineer magazine.
IEEE power industry experts bring their combined experience in the electrical power industry...
Michael Heinsdorf, P.E., LEED AP, CDT is an Engineering Specification Writer at ARCOM MasterSpec.
click me