The most common relay functions in an ATS panel are under-voltage, over-voltage, under-frequency, over-frequency, phase loss, phase sequence, and phase imbalance monitoring. In generator-backed systems, relays may also include reverse power, overload, earth fault, and. Low-voltage automatic transfer switch assemblies provide a reliable means of transferring essential load connections between primary and alternate sources of electrical power. Most modern ATS controllers and logic processors are also programmed with additional protection and operational. Protection relays in an Automatic Transfer Switch (ATS) panel are the intelligence layer that supervises source availability, system health, and transfer permissives in LV power distribution. They are intended to quickly identify a fault and isolate it so the balance of the system continue to run under normal conditions.
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