Which class of devices is excluded from overcurrent protection?

Starter motors are a specific class of devices that operate under unique conditions during their operation, which is why they are generally excluded from standard overcurrent protection requirements. Overcurrent protection is crucial in preventing damage to electrical circuits and components by interrupting excessive current flow. However, starter motors typically experience high inrush currents when they engage, which can be many times higher than their rated current.

This high inrush is necessary for the motor to overcome inertia and start under load. If starter motors were subjected to normal overcurrent protection, such as fuses or circuit breakers, these protective devices would likely trip during the starter's normal operation, leading to unwanted interruptions. Instead, starter motors often have their own dedicated system for handlings such conditions, which does not require traditional overcurrent protection methods.

Battery chargers, circuit breakers, and alternators, on the other hand, are designed to work within specific current limits and do require overcurrent protection to safeguard against failures and potential hazards.