The Siemens 3UG4583-1CW31 is a SIRIUS-brand insulation monitoring relay with analog setting, designed to continuously measure the insulation resistance of an ungrounded AC or DC system (IT system) and trigger an alarm or trip when the resistance falls below a set threshold. It monitors AC or DC systems up to 400 V (measurable voltage range 0...400 V AC/DC) and accepts line frequencies from 15 to 400 Hz, covering both standard 50/60 Hz supplies and higher-frequency loads such as motor drives or generators. The relay is powered by a wide-range control supply of 24...240 V AC/DC, so one unit works across global control voltages without a separate transformer tap.
Surge voltage resistance rated at 4000 V (impulse) ensures the relay withstands transient overvoltages common on industrial power networks without failing — important for reliability in high-inductance environments. Screw-type terminals accept solid wire up to 12 AWG (1x 20...12 AWG, 2x 20...14 AWG) and stranded wire up to 14 AWG (1x 18...14 AWG, 2x 18...16 AWG), with finely stranded cores up to 2.5 mm² prepared with ferrules — typical for panel wiring.
RoHS compliance date of 05/01/2012 confirms it meets the EU Restriction of Hazardous Substances directive for current production.