1. Reasons: Excessive water supply causes the motor to be overloaded; Motor phase loss; The vent hole is blocked; Impeller dragging other parts 2, the solution: Reduce the water supply to the normal range (refer to the supply volume of the water ring vacuum pump instruction manual); Check that the wiring is secure; Check the exhaust port; Open the water ring vacuum pump cover to adjust the clearance between the impeller and other components ATC Cnc Router,High Quality ATC Cnc Router,ATC Cnc Router Details, CN Shandong U-May CNC Technology Co., Ltd. , https://www.sesamecnc.com