CM-PVS Three-Phase Monitoring Relays The CM-PVS.x1 are monitoring relays for three-phase mains. They monitor the phase parameters phase sequence, phase failure, over- and undervoltage. The threshold values for over- and undervoltage are adjustable. Monitoring of three-phase mains for phase sequence (can be switched off), phase failure, over- and undervoltage Threshold values for over- and undervoltage are adjustable as absolute values Tripping delay can be adjusted or switched off by means of a logarithmic scale ON-delayed or OFF-delayed tripping delay selectable Powered by the measuring circuit True RMS measuring principle 2 c/o (SPDT) contacts 3 LEDs for status indication