The Siemens 3UG3532-1AC40 is a SIRIUS monitoring relay measuring voltage from 15 to 600 V AC/DC with a single changeover contact (1CO) and a 24 V DC coil.
The 15…600 V AC/DC measuring range covers most low-voltage and control-voltage levels found in industrial panels — from 24 V control circuits up to 480 V motor feeds. The 1CO contact (one form C) gives a single normally-open and normally-closed output, enough to signal a PLC input or trip a contactor coil. The 24 V DC coil supply is standard for modern digital I/O systems; if your panel runs 120 V AC control, you'll need a different coil variant. IP20 protection means the relay is safe from finger contact but not from dust or moisture ingress — mount it inside a closed cabinet, not in a wet area.