Pressure Adjustable:The water pump pressure is adjustable through this switch and you can set the adaptable pressure as you the work needs. Instructions；1 phase or 3 phase (15 or 230 volt / at 115 volt 1 phase it will handle 1.5 hp, at 230 volt 1 phase it will handle 2 hp, and at 230 volt 3 phase it will handle 3 hp.).
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