Thomas Edison Study Guide: AC/DC

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Ironically, the people who paved the way for Westinghouse's AC system to become the dominant electrical system in the United States were former Edison employees. One of these, Nikola Tesla, was a Serbian electrical engineer who came to the United States to work with Edison in 1884. He left the Edison factory to develop his own inventions and is credited with inventing the polyphase induction motor, a device, which allowed for long-distance application of AC electrical power. The other invention was a rotary converter by Charles Bradley, another former Edison employee. The converter was patented in October 1888 and combined elements of the AC system with the DC system, making it possible to connect high-voltage transmission lines to the DC central station and distribution networks. Thanks to these inventions, plus the hard marketing work of Westinghouse, AC systems were America's primary electrical distributors by the 1920s.

Analysis

Edison learned in the mid-1880s that he could be on the losing end of court battles and market share despite his winning streak. Once again, this was a valuable and painful lesson about the business world that he applied to his later inventions. From the battles with Joseph Swan, Edison learned that patents were invaluable, but only if they established precedence over the idea as well as the product. He also learned that settling out of court could save time and money for both parties.

The battles with Westinghouse introduced Edison to the fight for market share in the most ruthless ways. As he had learned from his experience with Alexander Graham Bell, a patent for a commercially successful product could be circumvented if an inventor could improve on that product in a new and unique way. To be on the opposite end of that principle, however, was a shock. And unlike his experience with Bell, the courts did not save Edison from losing the competition. The public made the final judgment on AC vs. DC systems, and Westinghouse was declared the winner.

To his credit, Edison fought a grim and tenacious battle against Westinghouse. And while he was most concerned with preserving his own market share, he was very concerned about the potential public hazards of using such a high-voltage system. His press packets on the danger of AC systems contained truth, and he would eagerly demonstrate his points for the press by using high voltages to electrocute stray cats and dogs in the Menlo Park laboratory. At the very least, Edison's loud protestations for public safety forced Westinghouse to take comprehensive safety precautions in developing his AC system on a large scale.

The defection of Edison employees brings up another point about Edison's behavior as the chief inventor at the Menlo Park laboratory. While Edison emphasized a non-hierarchical structure at the laboratory, he was very careful to make it clear that all inventions at the Menlo Park laboratory belonged to him. Employees were not encouraged to make their own inventions and file their own patents. While this arrangement was crucial for infringement concerns, it discouraged many talented young inventors. They grew frustrated with the rules at Edison's laboratory and struck out on their own, often creating devices that helped Edison's competition.

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