PumpSaver 233P Pump Saver Protects pumps from dry-well, dead-head, rapid-cycling, jammed impeller, and over/undervoltage. Protects 230 volt, 2 or 3 wire, 1/3 to 3 hp pumps For single-phase pumps. For residential and commercial water wells, irrigation wells, golf course and sprinkler systems. Buy with trust from the the author of The Pump Book and former President of CGA.