The Siemens SIRIUS 3UG4582-1AW30 is an insulation monitoring relay with analog setting, part of the SIRIUS brand family. It continuously monitors insulation resistance in ungrounded AC/DC systems (IT systems), triggering an alarm when resistance drops below a set threshold. It draws its control supply from 24 to 240 V AC/DC (at 50 or 60 Hz), and the measurable voltage range on the monitored circuit is 0 to 250 V AC. The operating frequency range spans 15 to 400 Hz, covering standard power frequencies and higher-speed motor drives. The response threshold is adjustable between 0.85 and 1.1 times the full-scale value, with a delayed switching time of 1 second to avoid nuisance trips from transient leakage. An error memory (latching) option is built in, so a past fault stays indicated until manually reset.
The enclosure is 22.5 mm wide, 78 mm high, 100 mm deep — a single-module footprint that fits tight panel layouts. No clearance required upwards, downwards, forwards, or backwards (0 mm all around). Mounting position is any orientation. Connections are screw-type terminals accepting solid wire 20–12 AWG (0.5–2.5 mm²) and stranded 18–14 AWG (0.75–2.5 mm²) with ferrule. Tightening torque is 0.6–0.8 N·m. No auxiliary contacts or delayed NC/NO contacts are provided — this is a single-function monitoring relay.
Environmental and surge ratings
Surge voltage withstand is 6000 V, giving solid margin for transient-heavy environments like motor control centers or VFD cabinets.