How To Deal With Low Flow Rate And Decreased Insulation Resistance Of Submersible Pumps?（ONE）

Aug 06, 2024

1, Reasons why submersible pumps cannot be started
1. The power supply voltage is too low
The solution is to adjust the voltage to above 342V. In emergency situations of disaster relief and drainage, submersible pumps must be used, and when the voltage is below 342V, the setting current of the submersible pump protection switch can be appropriately increased. However, during use, the current should be controlled to not exceed 1.1 times the rated current of the motor, and the usage time should be controlled to prevent the motor from being overloaded for too long, which may cause overheating and damage to the stator winding.
2. Power supply phase failure or power outage, such as cable core wire breakage, fuse melting, poor contact of control and protection switches, protection device action, etc
The solution is to carefully inspect the fuses, control protection switches, and protective devices to check if there is a power failure or interruption, or if it is caused by the action or contact of the fuses, control protection switches, and protective devices. Then repair the power failure or interruption caused by the fuses, control protection switches, and protective devices. If it is caused by a power interruption, the power supply should be restored.
3. The impeller of the water pump is stuck
The solution is to dismantle and inspect the water pump, remove debris, and ensure that the submersible electric pump can operate normally.
4. The cable is too thin, too long, and the voltage drop is too large, causing the power supply voltage of the submersible pump to be too low and the motor to be unable to move
The handling method is to appropriately thicken the cable section when the submersible pump is used far away from the power source, the cable is long, and the voltage drop is too large. If the cable length is doubled, the cable cross-section should also be doubled accordingly.
5. Poor contact of plugs, switches, and other connectors of submersible pumps
The solution is to repair or replace the poorly connected connectors.
6. Action of thermal protector
The solution is to first check the cause of the thermal protector's action. If the cause of the thermal protector action is a malfunction of the submersible pump, the fault should be immediately identified and resolved; If the reason for the action of the thermal protector is caused by the overload of the motor, the cause of the overload should be identified and eliminated, such as whether it is due to the low power supply voltage causing the motor current to be too high; Is the impeller entangled by debris and not rotating smoothly; Is it due to bearing damage, causing the stator and rotor of the motor to rub against each other and high ambient temperature.
The action of the thermal protector indicates that the temperature of the submersible pump has exceeded the rated temperature. The submersible pump can only resume operation after the temperature of the stator winding decreases and the thermal protector automatically resets.
7. Damaged thermal protector
The solution is to first check the cause of the damage to the thermal protector. If the cause of the damage to the thermal protector is due to a malfunction of the submersible pump, the malfunction of the submersible pump should be immediately investigated and eliminated; If the cause of damage to the thermal protector is due to its quality or prolonged use, it should be replaced with a thermal protector of the same model and specifications.
8. The stator winding of the submersible motor is damaged
The handling method is to first check the cause of the damage to the stator winding of the submersible motor, eliminate the fault, and prevent further damage to the stator winding of the submersible motor. Then, disassemble and repair the stator winding of the submersible motor, and replace the damaged stator winding as required.
9. Poor or damaged contact of single-phase submersible motor centrifugal switch
The solution is to first check whether the cause of the centrifugal switch damage is related to the malfunction of the submersible pump. If there is a malfunction in the submersible pump, it should be immediately found and eliminated, and then the centrifugal switch should be repaired or replaced.
2, Why does the fuse of the submersible pump burn off after being connected to the power supply? How to handle it?
The burning of the fuse after connecting the submersible pump to the power supply is related to factors such as low voltage of the power supply, malfunction of the water pump and motor, and improper use.
1. The reason for the two-phase operation of the submersible pump should be checked
The handling method is: if it is caused by a two-phase fault of the power supply, the damaged power supply should be repaired; If it is caused by a malfunction of the submersible pump, it should be inspected and repaired.
2. The impeller of the submersible pump is blocked by debris and experiences severe friction
The solution is to disassemble the submersible pump, remove debris from the pump impeller or flow channel, and make the submersible pump rotate smoothly and lightly.
3. The power supply voltage is too low
The low power supply voltage prevents the submersible pump from starting. The solution is to adjust the power supply voltage to 342-400V so that the submersible pump can start smoothly.
4. The bearing of the submersible pump motor is damaged
Damage to the bearings of the electric motor can cause the submersible pump to malfunction and increase the current. The solution is to replace the damaged bearings of the submersible pump.
5. Bending of the submersible pump shaft and misalignment between the stator and rotor are serious fault situations that can cause uneven air gaps in the submersible motor, deterioration of shaft bearing capacity, and even friction between the stator and rotor of the submersible pump, resulting in severe vibration during operation. Immediate repair should be carried out to straighten the bent shaft and replace the unqualified bearings.