Analog monitoring relay Phase sequence monitoring 3 x 320...500 V 50...60 Hz AC 2 change-over contacts spring-type connection system Network monitoring relay with analog setting SIRIUS 3UG4 for monitoring phase sequence, phase failure and phase asymmetry and/or undervoltage, e.g. with mobile systems such as A/C compressors, refrigerated containers, construction site compressors or cranes. Worldwide use thanks to international certificates. Different versions enable application-related selection of products. Less space required in the control cabinet thanks to slim design. All versions with removable terminals. In addition to screw terminals, all the devices are also available with spring-type terminals for fast, maintenance-free and vibration-proof connection. Versions with a wide voltage range and without auxiliary voltage can be used in any networks worldwide. The comprehensive range of accessories, such as unit labeling plates, push-in lugs and cover caps, is standardized for all relays. SIRIUS relays - one range for every application.