The Siemens 3UG4631-2AW30 is a SIRIUS voltage monitoring relay with a digital LCD setting interface — you dial in the thresholds directly on the front panel, no trim pots or guesswork. It monitors AC or DC systems from 24 to 240 V (50/60 Hz) and trips on overvoltage or undervoltage, with a relative repeat accuracy of 1 % of the full-scale value. The relay output is rated 1 A at 24 V, 0.2 A at 125 V, and 0.1 A at 250 V — these are the contact limits for the alarm or trip signal, not a motor-switching contactor.
Snap-on mounting on a 35 mm DIN rail, 22.5 mm wide, 94 mm tall, 91 mm deep — fits the standard SIRIUS modular profile alongside contactors and motor starters. IP20 rated, so it belongs inside an enclosure, not on the machine frame.