Letters

Don't hesitate.
Tell us what you like and what we can do better. Share your thoughts and experiences.

Dear PACWorld,
I enjoy the magazine, but in some ways the paper version is less convenient. I would prefer to have a PDF of the whole issue to save on my computer and to search for content. This means I can have the past issues with me when I am at work, and can catch up when I am travelling and when I don't have internet service.

Would you consider generating a single PDF for each issue for subscribers to download? This is what other industry magazines such as T&D World do. I would be prepared to only receive an electronic version, but ideally would get both to start with.

Thanks,
David Ingram, PhD, Australia

PAC World:  
Dear David,
We have been considering producing an electronic version of the magazine and I am sure that many of our readers feel the same. The main reason that we have not produced a PDF file of the complete magazine has been that the single file will be very big.

You probably know that subscribers to the magazine can download from the web site PDF versions of individual articles that they can save on their computers for off-line use.
We will produce a single PDF file of the magazine for the June 2014 issue and we would like to see what you and the rest of our readers think about that.


Dear Editor,
It was great to read the article on Digital Protection History in the March 2014  of the PAC World magazine.  Working in North America I had no experience on the European development of the digital protective systems.  I appreciate the insight and found the information very interesting.   As you further develop these articles I assume the impact that Ed Schweitzer and the Western Protective Relay Conference had on the development of digital relays will be discussed. 

As a new engineer, meeting with Ed on one of his first sales calls in 1982 or 1983 and purchasing several of his SEL-21 relays for fault locating was very exciting. How they handled the memory stack to ensure 100% relay response and still allow the user to communicate with the relay and not affect the response of the relay was fantastic.  I believe all of this was with a 8 bit processor, if I remember correctly. We used his digital relay fault location to reduce hours off of line patrol on the Northern

States Power’s 69kV system and to allow quicker restoration, in the early 1980s. I believe that no article on Digital relaying history would be complete without including Mr. Schweitzer and the SEL family of relays.
Looking forward to reading the future articles and thanks for writing these.

Thanks
 Craig Turner

PAC World:  
Dear Craig,
Thank you for your interest in the magazine and your appreciation of Mr. Shossigs’s work.
The topic of the history of microprocessor based protection is a very interesting and challenging one, because there are still many PAC specialists that personally witnessed this history. Mr. Schossig spends tremendous amount of time searching for all available sources to write his articles. If you try to do this yourself you will find out how difficult it is.

That is why we sent e-mails to all protection and control IEDs manufacturers asking for information about the history of their use of microprocessors in their protection relays.

This and the next few issues will include articles on this history in alphabetical order. Based on the information that we have received so far, the contribution of Schweitzer Engineering Laboratories will be covered in the September 2014 issue of the magazine.


pac world:

Editor in chief: dr. Alexander Apostolov (USA)
Editors: Christoph Brumer (Switzerland), Yana St. Clair (USA)
Design Layout Concept: Marek Knap (Poland)
Graphic Design: Iagoda Lazarova (USA),
Dan-Andrei Serban (Romania)
Web Master: Ognian Samokovliiski (Bulgaria)

Advisory Board:

Christoph Brumer (Switzerland), dr. Damir Novosel (USA), Graeme Topham (South Africa), dr. Iony Patriota (Brazil), Jorge Miguel Ordacgi Filho (Brazil), prof.
Mohindar Sachdev (Canada), prof. Paul Lee (Korea), prof. Peter Crossley (UK), Rannveig Loken (Norway), Rodney Hughes (Australia), prof. Xinzhou Dong (China

Address:
PAC World (Email: editor@pacw.org)
9002 Chimney Rock Rd, G389
Houston, TX  77096, USA
PAC World magazine is published quarterly by PAC World.  All rights reserved.  All published articles express solely the opinion of the authors. Reproduction in whole or in part of any material in this publication is allowed.
Parent company: OMICRON electronics Corp. USA

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