- 100 years since the MCB’s inception, innovation in electrical safety technology has become central to a safe net-zero journey as renewable energy sources require grid management
- ABB’s first-of-its-kind MCB continues to set industry standards for performance, compact size, connectivity, and transparency
- Flexible, time-saving designs enable easier installation, helping address the current industry skills shortage
ABB is celebrating the 100-year anniversary of the first-of-its-kind Miniature Circuit Breaker (MCB) in 2024, a significant milestone in protecting electrical circuits and evolving to meet the sustainability needs of the future. In the last century, the MCB facilitated electrical safety across sectors, from rail infrastructure to factories, commercial buildings, and data centers.
MCBs detect electrical faults like short circuits and overcurrents, disconnecting the circuit within 10 milliseconds, 10 times faster than the blink of an eye. The breaker can be reset quickly and easily without the need for replacement. As we transition towards a net-zero future, it is essential to increase electrification and integrate more diversified, renewable energy sources. This means protection devices have even greater electrical loads to manage along with variations in power supply and demand. ABB’s MCBs provide electrical safety to everything from solar panels and heat pumps to electric vehicles and brings additional protection against faults like residual currents, surges, ground fault currents, or arc faults.
Modular DIN-rail devices 
MCBs
Aldo Sciacca, Head of Energy Distribution, ABB Electrification’s Smart Buildings Division, says, “Our future-focused portfolio centers on achieving energy efficiency and transparent, sustainable practices. We also focus on easy installation, which is invaluable when facing skilled labor shortages. Through our compact, modular, and flexible designs, we’re enabling applications to be retrofitted and to integrate renewable energy sources, quickly and safely. This plays a vital role in ensuring the safe development of sustainable, modern communities, cities, and urban landscapes of our future.”
Today’s protection devices make applications around the world safer, smarter, and more sustainable. Compact designs enable retrofitting even in legacy equipment where space is limited.
Hugo Stotz at his electrical supplies company in Mannheim, Germany 
Today's facility at ABB-STOTZ Kontakt GmbH, Heidelberg, Germany 
Production line at ABB-STOTZ Kontakt GmbH, Heidelberg, Germany
History of the MCB
In 1918, ABB’s forerunner, Brown, Boveri & Cie (BBC), purchased Stotz Kontakt, an electrical supplies company based in Mannheim, Germany. The company’s founder, Hugo Stotz stayed on with BBC and, working with his chief engineer, Heinrich Schachtner, invented the first resettable Miniature Circuit Breaker, a device that was patented in November 1924.
By combining thermal and magnetic trips into a single, reusable unit, the MCB was patented in 1924, becoming capable of switching off high currents and becoming resettable, meaning devices didn’t have to be repeatedly replaced. Today, ABB has eight factories globally manufacturing MCBs with more than 100 million poles per year.
ABB is a technology leader in electrification and automation, enabling a more sustainable and resource-efficient future. The company’s solutions connect engineering know-how and software to optimize how things are manufactured, moved, powered, and operated. Building on over 140 years of excellence, ABB’s more than 105,000 employees are committed to driving innovations that accelerate industrial transformation. www.abb.com
ABB Electrification is a global technology leader making efficient and reliable use of electricity from source to socket possible. With more than 50,000 employees across 100 countries, we collaborate with our customers and partners to solve the world’s greatest challenges in electrical distribution and energy management. We help businesses, industry, and consumers run their facilities and homes efficiently and reliably. As the energy transition accelerates, we are electrifying the world in a safe, smart, and sustainable way. go.abb/electrification
