A 100A 4-pole automatic changeover switch (ATS) is a vital electrical device designed to seamlessly and automatically transfer power supply between two sources, typically the main utility grid and a backup generator or solar inverter.
The "100A" refers to its maximum current handling capacity, suitable for residential, commercial, or light industrial applications. "4-pole" indicates that it switches all four conductors (three phases and neutral) for a complete and safe transfer, often used in three-phase systems. The "automatic" function ensures uninterrupted power, as it senses a loss of primary power and swiftly switches to the secondary source, then reverts once the primary power is restored, all without manual intervention. This minimizes downtime and protects sensitive equipment.