The AVP3P is an Automatic Voltage Protector designed to protect three phase loads from voltage fluctuations, over voltage, under voltage, surges, dips and frequent start/stops. The output is a single volt-free changeover contact, rated at 16A. This is intended to control an external contactor, control circuit, start/stop system or alarm. If the voltage on any one phase goes above or below the pre-set limits (the 'window'), then the AVP3P will switch off. Once the voltage returns within the window limits, the AVP3P will wait for a pre-set time, continuing to check the voltages, before automatically turning the load back on. The over voltage, under voltage and delay settings are all adj u stable using controls in the terminal compartment of the AVP3P. The standard window that is considered acceptable is 185V-260V (320V-450V three phase). Outside these limits electronic and electrical equipment are likely to be damaged.