History of Circuit breaker in Timeline

By Popular Timelines Editorial Team · Updated: April 7, 2025

A circuit breaker is an electrical safety device that protects circuits from overcurrent, preventing damage and fires. It interrupts current flow when it exceeds safe levels. Unlike fuses, which are single-use, circuit breakers can be reset, allowing for resumed operation after the overcurrent situation has been resolved. They are a fundamental component in electrical systems, ensuring safety and preventing equipment failure.

1924: Patent of Modern Miniature Circuit Breaker

In 1924, Brown, Boveri & Cie patented a modern miniature circuit breaker, similar to those in use today. Hugo Stotz, an engineer who sold his company to Brown, Boveri & Cie, was credited as the inventor on German patent 458392. This invention was the forerunner of the modern thermal-magnetic breaker.

1935: Circuit Breakers at Boulder Dam Project

By 1935, specially constructed circuit breakers used at the Boulder Dam project used eight series breaks and pressurized oil flow to interrupt faults of up to 2,500 MVA, in three AC cycles.

2000: Introduction of the Disconnecting Circuit Breaker (DCB)

In 2000, the disconnecting circuit breaker (DCB), a high-voltage circuit breaker modeled after the SF6-breaker, was introduced. The DCB integrates the disconnecting function in the breaking chamber, eliminating the need for separate disconnectors.

November 2011: Siemens Launched 1,200 kV Breakers

In November 2011, Siemens launched 1,200 kV circuit breakers.

2012: ABB Presents CO2 High-Voltage Breaker

In 2012, ABB presented a 75 kV high-voltage breaker that uses carbon dioxide as the medium to extinguish the arc, working on the same principles as an SF6 breaker. By switching from SF6 to CO2, CO2 emissions can be reduced by 10 tons during the product's life cycle.