Ever since homes were electrified in the 1920s, electrical safety has been a growing necessity. With the invention of the first resettable miniature circuit breaker (MCB), patented 100 years ago in 1924, Hugo Stotz made history and revolutionized the world of electrical safety.

Until then, the challenge was that the fuse had to be replaced every time a fault occurred. The combination of a thermal and a magnetic trip unit in a single device became the "thermal-electromagnetic circuit breaker", capable of switching off high currents without the need for repeated replacement. The ubiquitous, convenient electricity that powers the lights, refrigerators, and other household appliances we so often take for granted would not be possible without this hidden guardian. It disconnects the circuit almost instantaneously in the event of a short circuit or overload, protecting occupants and their belongings from fire, electric shock, and other damage.

The production of modern MCBs and protection devices still follows Hugo Stotz's spirit of innovation and is carried out not only in Heidelberg, Germany but all over the world.

In our modern world, where electricity powers nearly every aspect of our lives, ensuring the safety of individuals and their surroundings is crucial. With lightning-fast responses to short circuits or overloads, MCBs interrupt the current in just 10 milliseconds - 10 times faster than the blink of an eye. When this happens, the breaker is exposed to intense heat ranging from 5,000 degrees to 6,000 degrees Celsius - temperatures capable of melting rocks. Yet, despite that, homeowners now simply flip the switch that has been tripped, and power resumes its flow.

Our protection devices do not only safeguard millions of buildings, assets, and lives worldwide each year but are also ready to maintain their vital role in protecting modern electrical systems for the next century.

ABB Miniature Circuit Breakers production sites