The PHOENIX CONTACT part EMD-FL-3V-400 is a versatile monitoring relay designed to monitor 3-phase voltages within a range of 280 to 520 V AC. This relay provides comprehensive protection by detecting undervoltage, window, phase sequence, phase failure, and asymmetry issues. Equipped with a wide-range power supply unit, this relay ensures reliable operation in various industrial settings. With 2 PDTs (potential distribution transformers), this monitoring relay is a crucial component for maintaining the stability and safety of electrical systems.