Previous Year Question
In a circuit breaker, current interruption is achieved when the arc is:
Correct answer: B
Explanation
Successful interruption requires the arc path to lose conductivity around current zero. Cooling and de-ionization remove energy and charged particles, rapidly increasing dielectric strength between the contacts and preventing arc re-establishment.
Step-by-step solution
Correct Answer
B — Cooled and de-ionized
Explanation
Successful interruption requires the arc path to lose conductivity around current zero. Cooling and de-ionization remove energy and charged particles, rapidly increasing dielectric strength between the contacts and preventing arc re-establishment.
Key Concept
Cooling and De-ionization
Exam Point
Extinguish arc = cool + de-ionize + restore dielectric strength.
Exam tip
Extinguish arc = cool + de-ionize + restore dielectric strength.
Quick method
Extinguish arc = cool + de-ionize + restore dielectric strength.