Why Was circuit breaker capacity rated in MVA not in Ka & KV ?
The circuit breaker capacity is often rated in MVA (Mega Volt-Amperes) rather than in kA (kiloamperes) or kV (kilovolts) because MVA represents the overall power handling capacity of the circuit breaker.
MVA takes into account both the voltage and current, providing a comprehensive measure of the electrical power that the circuit breaker can interrupt under short-circuit conditions.
The short-circuit capacity of a system depends on the available fault current and the system voltage.
While kA indicates the current-carrying capacity, kV represents the voltage level. MVA, on the other hand, combines both factors to express the total power capacity.
In summary, using MVA simplifies the representation of the circuit breaker’s capability to handle electrical power, considering both voltage and current simultaneously.