Circuit breaker tripping time

The time it takes for a circuit breaker to trip, also known as the tripping time, is an important parameter in electrical engineering. It refers to the time it takes for the breaker to detect an overcurrent or overvoltage condition and interrupt the electrical circuit.

The tripping time of a circuit breaker is typically measured in milliseconds (ms) and can vary depending on several factors, including:

  1. Type of breaker: Different types of circuit breakers, such as thermal-magnetic, electronic, or vacuum breakers, have different tripping times.
  2. Overcurrent level: The higher the overcurrent level, the faster the breaker will trip.
  3. Overvoltage level: The higher the overvoltage level, the faster the breaker will trip.
  4. Temperature: High temperatures can affect the breaker's tripping time.
  5. Age and maintenance: The tripping time of a breaker can increase over time due to wear and tear, and may be affected by maintenance or repair history.

Typical tripping times for circuit breakers are:

For example, a thermal-magnetic breaker designed for a 20 A circuit might have a tripping time of 20 ms when an overcurrent of 30 A is detected. This means that it would take approximately 20 ms for the breaker to detect the overcurrent and interrupt the circuit.

In general, circuit breakers are designed to trip quickly to prevent damage to equipment and to ensure safety. However, the tripping time can be affected by various factors, and it's essential to consider these factors when selecting and installing circuit breakers.