The Reason For The Excessive Current When The Submersible Pump Is Operating

There are many reasons for the excessive current when the submersible pump is operating. The main causes are related to the adjustment of the pump valve and the mechanical failure of the submersible pump motor. The reasons are as follows:
(1) Motor bearing wear, pump rubber bearing wear, and sealing ring wear. If the bearings of the motor or pump wear out, it will cause the submersible pump to be in an abnormal mechanical working condition. In severe cases, it may damage the submersible pump and burn out the stator winding. The solution is to repair or replace the damaged bearings and bushings.
(2) Wear of thrust bearings, wear of the impeller and lower cover plate of the submersible pump. This situation will also cause the submersible pump to be in an abnormal mechanical working condition. In severe cases, it may even damage the submersible pump. The solution is to check the cause of the thrust bearing wear. If it is due to the damage of the mechanical seal at the shaft extension end, causing sand, impurities, etc. to enter the motor cavity and causing excessive wear of the thrust bearing, then the thrust bearing, thrust plate, impeller, and lower cover plate that have worn out should be replaced. At the same time, the shaft extension end mechanical seal should also be replaced during the repair or replacement process.
(3) The flow rate of the submersible pump is either too large or too small. If the flow rate used by the submersible pump exceeds the specified range, it will cause the motor to overheat: for centrifugal pumps or mixed-flow pumps, if the flow rate is too high, the shaft power of the pump increases, which will lead to motor overload; for axial-flow pumps, if the flow rate is too low, the shaft power of the pump increases, resulting in motor overload. The solution is to appropriately adjust the valves. For centrifugal pumps or mixed-flow pumps, reduce the flow rate (for axial-flow pumps, increase the flow rate) to make the pump's flow rate fall within the normal usage range.
(4) The rotating shaft of the submersible pump is bent and the bearings are not concentric. This is a serious problem with the submersible pump. It is necessary to immediately carry out maintenance, straighten the bent shaft, replace the faulty bearings, and reassemble the submersible pump.