The ABB 1SVR730885R3300 is a compact three-phase monitoring relay designed to monitor a three-phase supply (L1-L2-L3, optionally with neutral) for supply integrity and safety. It detects phase failure (loss of a phase), phase sequence (correct order), phase unbalance, over-voltage, under-voltage, and interrupted neutral. When any monitored parameter goes outside preset limits, the relay triggers its output contacts. Adjustable trip delay and selectable ON or OFF delay prevent nuisance trips due to transient conditions or startup surges. The device is DIN-rail mountable with screw-terminal connections, suitable for control panels, switchgear, motor control centers, and industrial or commercial installations.
