We began Part 1 with the inception of the circuit breaker, in Thomas Edison’s shop in the 1870s. The Boston Electric Company was the first to manufacture and install a circuit breaker, about 20 years later in 1898. But these early breakers wouldn’t be familiar to you – or to your parents, or even your grandparents.
The First Miniature Circuit Breaker
The miniature circuit breaker you would recognize was born in 1924. A Swiss company called Brown, Boveri & Cie (BBC) patented the design, which was based on an earlier patent by Hugo Stotz. Stotz was an engineer who had founded an electrical society in Mannheim, Germany in 1891. He sold his company and patents to BBC, and they developed and patented the miniature circuit breaker in Germany. Stotz is credited as the inventor, and thus the grandfather of the modern, thermal-magnetic breakers in every home, office, and industrial property today.
Meanwhile, BBC stayed in business under the same name for over 60 years. In 1988, it merged with the General Swedish Electrical Limited Company (ASEA), and became ASEA Brown & Boveri (ABB). ABB still manufactures Stotz circuit breakers, and in 2014 they celebrated the 90-year anniversary of the original patent.