What type of protection on a manual starter prevents automatic restart after a power loss?

Undervoltage protection is designed to prevent automatic restart of equipment after a power loss. When the voltage drops below a certain threshold, this protection mechanism activates, disconnecting the electrical circuit to ensure that the equipment remains off until manual intervention occurs. This is crucial in applications where it is unsafe or undesirable for machinery to restart automatically after a power interruption, as it allows operators to assess the situation and ensure that everything is safe before resuming operation.

In contrast, while overload protection guards against excessive current that could cause overheating and damage to the motor, it does not prevent restart after a power loss. Surge protection focuses on protecting circuits from voltage spikes, and phase loss protection guards against the loss of one or more phases in polyphase systems, but neither of these functions directly addresses the concern of automatic restart after a power outage.