Digital monitoring relay for current monitoring, 22.5 mm from 2-500 mA AC/DC. Over- and under-voltage monitoring: AC/DC 24 V DC and AC 50 to 60 Hz without galvanic isolation from the measurement circuit. Start-up and fault peak delay from 0.1 to 20 s. Hysteresis from 0.1 to 250 mA. 1 changeover contact with or without error memory. Screw connection. Successor product to 3UG3521-1AC. Digitally adjustable current monitoring relay SIRIUS 3UG4 for monitoring currents for over- and under-voltage, e.g., to ensure the functionality of electrical consumers or for wire break monitoring. Worldwide use due to international certifications. The relay can be variably set for over-voltage, under-voltage, or window monitoring. Delay times and RESET behavior are freely parameterizable. Reduced space requirement in the control cabinet thanks to a narrow design width. Reliable diagnostics through the display of actual values and status messages. All versions come with removable connection terminals. In addition to screw connection technology, the devices are also available with spring-loaded connections for quick, maintenance-free, and vibration-resistant connections. They are also available in various voltages, optionally with IO-Link. The comprehensive accessories, such as device labeling plates, insertion tabs, and cover caps, are uniform for all relays. SIRIUS relays - a program for all cases.