Moshe Kam IEEE President
Official picture of Moshe Kam
Appointment of Dr. Moshe Kam to Dean, Newark College of Engineering
3 April, 2014

ENGINEERING AS A LIBERAL ART: an address to the Edinburgh International Cultural Summit (The Debating Chamber, Scottish Parliament; Edinburgh, Scotland; 14 August 2012)
14 August, 2012

Comments during the dedication of an IEEE Milestone on the World’s First Reliable High Voltage Power Fuse, 1909 (3 August 2012, Chicago, IL, USA)
3 August, 2012

Comments at the Dedication of the IEEE Milestone Mainline Electrification of the Baltimore and Ohio Railroad, 1895 (21 June 2012, Baltimore, MD)
9 July, 2012

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Comments during the dedication of an IEEE Milestone on the World’s First Reliable High Voltage Power Fuse, 1909 (3 August 2012, Chicago, IL, USA)

Ladies and Gentlemen, Friends and Colleagues:

I am pleased to represent the IEEE Board of Directors today on this happy occasion of presenting the milestone on the First Reliable High Voltage Power Fuse.  This is a somewhat different milestone than many of the ones that we have dedicated recently – and I will discuss this difference in a minute – but certainly it does not deviate from our previous recognized milestones in importance or in originality.  We are celebrating today a truly vital invention – the Schweitzer and Conrad Liquid Power Fuse – which by itself, and in the many variations that ensued, was vital to decreasing the failures and damages which too often were caused by improper circuit interruption at high voltages.   

The design – including the spring-loaded fusible element that melted when a short circuit current heated it, and whose ends were then pulled apart rapidly while the liquid inside the tube cooled and de-ionized the arc – this design continues to be a marvel that impresses today, more than a hundred years after it was introduced, as it undoubtedly delighted the engineers and technologists of the day.   It is elegant, in retrospect – simple, highly suited to the task, efficient and economical. 

The obstacles that Schweitzer and Conrad had to overcome involved several areas of expertise and disciplines, most importantly the design of the glass tube, which needed to withstand a 5000K arc in a fraction of a second after it was exposed to subfreezing temperatures.    As many of you know, the resulting boro-silicate glass appeared later in kitchens across America and the world under the Pyrex trademark, and ended up as the basis for important scientific devices such as the 200 inch telescope mirror at Palomar observatory.  In addition, we know that the first design was supplemented and replaced by many subsequent inventions by the original inventors, including the 1922 bayonet-style ejector cutout, and then several important devices that addressed the other key problem faced by utilities besides interrupting short circuits, namely switching a live load. 

What makes this 1909 invention different than milestones say by Tesla, Marconi, Edison and Popov that IEEE has celebrated over the years and around the globe is that – try as we might – this is truly a landmark for us engineers, a breakthrough that in all likelihood we will not be able to share widely with the public. 

Much has been said and done in the last couple of years about the need to popularize engineering and computing in the general public, and especially among young people. Yet it is not true – as sometimes alleged – that popular icons include only singers, dancers, and popular musicians.  Individuals from the core of engineering work such as Bill Gates, Steve Wozniak, Steve Jobs, Andrew Grove and Gordon Moore are not unknown – they are recognized by the well-educated and some of them are actually recognized almost universally.  However, Schweitzer and Conrad, who have worked on a problem of great significance to public welfare, and whose inventions have enabled the safe and inexpensive supply of electricity for millions, are probably destined to be remembered only by us, the relatively few who are closer to their field of interest and who can appreciate fully the ingenuity and importance of their life’s work. 

In this respect, what we are doing today is not so much an outreach to the masses, but an act we take internally, for the honor of our own, and for the deep appreciation that we show to individuals who were true pioneers. These are, one can say, electrical engineers’ engineers, who analyzed a problem (in their case manifested through the fire that they have studied – the 1909 Com Ed Fisk Generation Station fire in Chicago); learnt the lessons; defined the challenge; developed solutions and variations; tested and refined their solution; and, let us not forget, protected their intellectual property.  This protection in turn has enabled the creation of wealth and employment; established the base for the very fine and important corporation under whose auspices we are gathered today; prompted the continuation of pertinent research and development for many decades, fueled by the spirit of invention and practicality; and gave rise to numerous advanced devices for relaying and protection.  These include the S&C 1959 Circuit Switcher, the Fault Filter Power Fuse of the 1980s, the Scada-Mate Switching System of the 1990s and Intelli-Rupter introduced in 2009. 

In a 1961 publication of S&C, the author discussed “tomorrow’s switching,” and indicated that tomorrow’s switching would be performed “with sophistication rather than brute force.” Perhaps this is the best way for us to describe the magnificent achievement of Edmund Schweitzer and Nicholas Conrad, long relegated to the specialized history of Electrical and Power Engineering, and yet extending influence over many generations of practical yet sharp and focused engineers.  After all, isn’t this the essence of what we try to accomplish throughout our profession, inspired by thinkers and doers like Schweitzer and Conrad – “with sophistication rather than brute force”?



C. Cook et al. (2011): Taming the Arc, IEEE Industry Applications Magazine, September/October 2011, pp. 8-12.

Moshe Kam ( ) ECE Department, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104, USA
The opinions expressed on this website are the opinions of the author and not necessarily the opinions of the IEEE