A relay with inverse-time characteristics operates how?

A relay with inverse-time characteristics is designed to operate more quickly as the current increases. This type of relay is used in protective relaying applications, particularly for devices like circuit breakers or overload relays. The fundamental principle of inverse-time characteristics means that the greater the level of excess current detected, the faster the relay will trip.

This design is beneficial because it allows for rapid disconnection of power in situations where a fault condition exists, such as a short circuit or overload. If the system experiences higher levels of current, it poses a greater risk to equipment and safety, so the relay effectively responds by tripling more quickly.

This characteristic creates a protective mechanism that balances the need for operation during normal conditions while ensuring that issues are addressed swiftly to prevent damage or hazards. The other options do not accurately describe this behavior: slow operation with increasing current or constant operation is contrary to the purpose of a relay designed with inverse-time characteristics. Additionally, a relay that only operates when current is reduced does not align with how these protective devices function.