Incorrect phase sequence or phase failures are detected by the PFEmecotron, a three-phase monitoring relay. The unit, which is just 22.5 mm wide, operates over a supply range of 208 to 440 vac, 50/60 Hz. An incorrect phase sequence or phase failure causes the unit’s 4A SPDT output relay to open, thus providing an immediate alarm signal to production machinery, pumps, motors, elevators, transportation equipment, or other equipment containing three-phase electrical networks. Unit can be snapped onto a DIN rail or panel mounted with an adapter. The relay is rated for 30 million operations mechanically and 100,000 operations electrically.