What it is and what it does
The Siemens SIRIUS 3UG4625-1CW30 is a residual current monitoring relay with digital setting, designed specifically for three-phase supplies. It monitors residual current in the range of 30 mA to 40 A, adjustable via the digital interface, and operates on a wide supply voltage of 24 to 240 V AC/DC. This makes it a versatile choice for detecting ground faults or insulation degradation in motor feeders, distribution panels, and industrial loads.
Mounting and environment
Screw and snap-on mounting onto 35 mm DIN rail — standard for any European-style panel. Width is 22.5 mm, so it takes one slot in a terminal-block-style rail. IP20 at the enclosure and terminals means it's protected against solid objects larger than 12.5 mm (fingers, tools) but not against water ingress — keep it inside a rated cabinet. Operating temperature range is -25 to +60 °C, which covers most indoor industrial environments without derating. Pollution degree 3 means it's suitable for conductive environments (condensation, occasional dust) typical of control rooms and light industrial floors.