This three-phase monitoring relay is designed for phase failure detection, phase sequence monitoring, and over/under voltage protection. It has a measuring range of 300-500 VAC (L-L) and a start-up delay of 200ms. The tripping delay can be set to either 0s or within the range of 0.1-30s. The relay features two changeover contacts with a rating of SPDT 4 A/250V. It operates at a control supply voltage of 1 and has a compact width of 22.5 mm per module.