History of circuit breaker standards

The history of circuit breaker standards dates back to the early 20th century, when the first circuit breakers were developed. Over the years, standards have evolved to ensure the safety and reliability of electrical systems. Here's a brief overview of the major milestones in the development of circuit breaker standards:

Early Years (1900s-1920s)

• The first circuit breakers were developed in the early 20th century, primarily for industrial and commercial applications.
• There were no standardized specifications or testing procedures for circuit breakers at this time.

First Standards (1920s-1940s)

• In the 1920s, the American Standards Association (ASA) published the first standard for circuit breakers, known as ASA C37.1.
• This standard covered the general requirements for circuit breakers, including electrical and mechanical characteristics.
• In the 1930s, the International Electrotechnical Commission (IEC) published its first standard for circuit breakers, known as IEC 255.

Post-War Developments (1940s-1960s)

• After World War II, there was a significant increase in the demand for circuit breakers, driven by the growth of the electrical industry.
• In the 1950s, the National Electric Manufacturers Association (NEMA) published its first standard for circuit breakers, known as NEMA AB 1.
• The IEC also published several updates to its standard, including IEC 255-1 (1955) and IEC 255-2 (1961).

Modernization (1970s-1990s)

• In the 1970s, the International Electrotechnical Commission (IEC) published a new standard for circuit breakers, known as IEC 60228.
• This standard introduced new requirements for circuit breaker performance, including fault current interruption and arc extinction.
• The National Electric Manufacturers Association (NEMA) also published several updates to its standard, including NEMA AB 1-1974 and NEMA AB 1-1986.

Current Standards (2000s-present)

• In the 2000s, the International Electrotechnical Commission (IEC) published a new standard for circuit breakers, known as IEC 60228-1 (2004).
• This standard introduced new requirements for circuit breaker safety, including protection against electrical shock and fire hazards.
• The National Electric Manufacturers Association (NEMA) also published several updates to its standard, including NEMA AB 1-2002 and NEMA AB 1-2011.

Recent Developments

• In recent years, there has been a growing focus on the development of standards for specific types of circuit breakers, such as:
  • Low-voltage circuit breakers (LVCBs): IEC 60228-1 (2004) and NEMA AB 1-2011
  • Medium-voltage circuit breakers (MVCBs): IEC 62271-100 (2017) and NEMA C37.20.1-2019
  • High-voltage circuit breakers (HVCBs): IEC 62271-100 (2017) and NEMA C37.20.1-2019

Overall, the development of circuit breaker standards has been driven by the need to ensure the safety and reliability of electrical systems. As technology has evolved, standards have been updated to reflect new requirements and challenges, such as the need for increased fault current interruption and arc extinction capabilities.