What this relay monitors and where it fits
The Omron K8AK-PA2-AC380/480 is a monitoring relay that detects phase sequence and phase loss on a three-phase AC supply. It is designed for panel mounting in motor control centres or distribution boards where incorrect phase rotation or a dropped phase could damage rotating equipment or cause a process fault.
Supply voltage and wiring note
This variant is rated for a nominal supply of AC 380/480 V — the operating voltage range is printed on the device label and governs the coil input, not the monitored line voltage. The relay's own power comes from the same three-phase lines it watches, so wiring must follow the terminal markings for, L2, L3 and the output contacts.