Which of the following circuit breakers will produce the least arc energy?

The minimum oil circuit breaker is designed with specific operational characteristics that effectively limit the arc energy produced during the interrupting process. Unlike other types of circuit breakers, which rely on oil as a medium for arc extinction, the minimum oil design requires only a small amount of insulating oil. This reduction in oil volume lowers the total energy that can be converted into arc energy.

During operation, when a fault occurs and the contacts within the circuit breaker separate, an electric arc is formed. The energy from this arc is influenced by several factors, including the medium used for quenching the arc. In the case of the minimum oil circuit breaker, the small quantity of oil minimizes energy release, as it is specifically engineered to interrupt the current more efficiently and with less energy loss compared to plain oil or air blast circuit breakers.

Plain oil circuit breakers, which utilize a larger volume of insulating oil, have the potential to produce greater arc energy due to the increased oil mass that can contribute to the energy of the arc. Air blast circuit breakers, while innovative in using compressed air for arc extinction, can also produce higher arc energy when compared to a minimum oil circuit breaker because of the different mechanisms involved in quenching the arc.

Therefore, the minimum oil circuit breaker stands out by producing