The ALTECH part 900VPR-2-280/520V-CU is a highly advanced and compact Self Powered Voltage / Phase / Frequency Protection Relay. It is designed to accurately monitor and protect electrical systems against voltage, phase, and frequency anomalies. With its integrated LCD display, users can easily access and interpret crucial information in real-time. This reliable protection relay is an ideal choice for industrial and commercial applications, ensuring uninterrupted power supply and preventing damage to equipment.