Phase monitoring relay with digital setting
The Siemens SIRIUS 3UG4614-1BR28-0AA3 is a network monitoring relay that watches for phase loss, phase sequence, and asymmetry on three-phase AC supplies from 160 to 690 V at 50 or 60 Hz. It's got a digital LCD display for setting thresholds and a delayed-switching output rated 3 A at 250/400 VAC. Snap it onto a DIN rail — 22.5 mm wide, any orientation — and it'll run from -25 to +60 °C ambient. Asymmetry detection is built in, so it'll catch an unbalanced load before a motor cooks. The output has auto-reset capability, and the start-up delay is adjustable from 0.1 to 20 seconds — handy for riding through momentary dips without nuisance trips.
The 3 A contact rating at 250/400 VAC (50/60 Hz) is the switching capacity for the relay output — enough to drive a contactor coil or a small load directly. The solid and stranded wire range is 20–14 AWG, and the screw terminals accept two conductors per clamp. The LCD display shows measured values and settings; no LED version on this variant.