Digital monitoring relay voltage monitoring, 22.5 mm from 17-275 V AC/DC overshoot and undershoot self-powered interference peak delay 0.1 to 20 s hysteresis 0.1 to 150 V 1 changeover contact spring-loaded technology spring-loaded technology Digitally adjustable voltage monitoring relay SIRIUS 3UG4 for monitoring voltages for overshoot and undershoot, e.g. to protect a system from damage, to protect against battery deep discharge or to switch on a system from a defined voltage. Worldwide use thanks to international certificates. The relay can be variably set to overshoot, undershoot or window monitoring. Delay times and RESET behavior can be freely parameterized. Less space required in the control cabinet thanks to a narrow width. Reliable diagnosis through display of ACTUAL value and status messages. All versions with removable connection terminals. In addition to screw connection technology, the devices are also available with spring-loaded connections for a quick, maintenance-free and vibration-proof connection. The devices are divided into self-powered and externally powered devices, optionally with a wide voltage range or with IO-Link. The comprehensive range of accessories, such as device identification plates, push-in tabs and cover caps, is standard for all relays. SIRIUS relays - a program for all situations.