Why is the submersible pump not pumping water due to too high current?

Submersible pumps are easy to use and have low installation costs, and are widely welcomed by users. Although submersible pumps are easy to use, they often have operating problems. What is the reason why the submersible pump current is too high and does not supply water?
(I) Cut off the power supply and pull the submersible pump out of the water to the shore. Check whether the impeller is entangled or stuck by foreign objects. The motor cannot rotate and the current increases, causing heat.
(ii) If there is no foreign matter entangled, check whether the impeller rotates smoothly. (It is impossible for the impeller of a submersible pump to rotate multiple times as smoothly as a general motor by adding force. The submersible pump can rotate as long as the seal is tight.
(iii) If it cannot rotate even after being rotated, it is likely that the rotor bearing is damaged. If the motor rotor is swept, the bearing should be replaced, and both bearings should be replaced at the same time.
(iv) Open the junction box to check whether the three motor lead wires are firmly pressed, and then use the multimeter ohm RX1 gear to measure whether the three-phase winding is normal. If one phase of the three phases is not connected to the other two phases, it means that the motor is damaged, and the current is increased but the water does not flow.
(v) Use the same gear of the multimeter to measure whether the three-core cable is broken. If one of the three cores is not connected, it means that the submersible pump is running in single-phase and the current is increased but the water does not flow.
(vi) The power source is missing and the submersible pump is running in single-phase. The submersible pump current is increased and the motor cannot rotate and the water does not flow. At this time, use the multimeter Use the 500V voltage range of the energy meter to measure whether the three-phase voltage at the upper port of the knife switch is normal, and then measure the lower port. If the voltage at the lower port is abnormal, it is likely that the internal wiring of the switch is loose, disconnected, or the switch is damaged, resulting in large current or no water.
(VII) Single-phase 220V submersible pumps generally do not have power supply problems. Regardless of whether the neutral wire or the live wire is broken or has poor contact, the motor cannot rotate. If a single-phase submersible pump has such a fault, you should start to check the mechanical parts.