What is the purpose of short time settings on breakers?

Short time settings on breakers are designed to provide delayed short-circuit protection. This feature allows the circuit breaker to withstand temporary fault conditions, such as those caused by inrush currents when motors start up or temporary short circuits. By having a delay, the breaker avoids unnecessary tripping during these transient conditions, allowing the circuits to continue functioning normally.

This setting ensures that the breaker will only operate after a predetermined time if the fault persists, thus safeguarding the electrical system from damage while still providing protection against sustained overcurrents that indicate a fault. In contrast, the other options pertain to different protective functions that do not align with the purpose of short time settings. Instantaneous overload protection reacts immediately to overload conditions, ground fault protection addresses issues related to current leaking to ground, and overvoltage protection is focused on preventing damage from voltage surges, none of which are relevant to the specific operation of short time settings.