The Siemens 3UG5651-1CW30 is a digital monitoring relay for speed, covering 0.1 to 6000 r/min with overshoot and undershoot detection. Supply voltage is 24 to 240 V AC/DC, 50/60 Hz, with on-delay and tripping delay adjustable from 0.1 to 999.9 s. Two changeover contacts on screw terminals handle the output.
The 0.1–6000 r/min range covers everything from slow conveyor shafts to high-speed spindles; the adjustable on-delay and tripping delay let you filter out transient speed dips without nuisance trips. The wide supply voltage (24–240 V AC/DC) simplifies panel wiring — one relay works across control voltages without a separate power supply module.