Usage And Maintenance Of Submersible Pumps

Submersible pumps often burn out the motor winding due to a lack of water in the pool. In response to this situation, several protection measures for submersible pumps have been compiled today: water shortage protection, motor leakage protection, oil chamber leakage protection, insulation resistance protection, winding overheating protection, bearing overheating protection, etc.
Prohibit abnormal startup of power supply voltage
Due to the long length of low-voltage power supply lines, it is common for the voltage at the end of the line to be too low. When the speed of the submersible pump motor decreases, the phase voltage is below 198 volts and the line voltage is below 342 volts. Starting the centrifugal switch will close, causing the starting winding to be electrified and heated for a long time, and even burning out the winding and capacitor. On the contrary, high voltage can cause the motor to overheat and burn out the windings. Therefore, during the operation of the submersible pump, the operator must always observe the power supply voltage value. If the motor stops running, identify the cause and troubleshoot.
Determine the correct direction of rotation of the motor
We should find out the direction of rotation of the motor. At present, high head submersible pumps can produce water during forward and reverse rotation, but the water output during reverse rotation is small, the current is high, and a long reverse time can damage the motor winding
Installation and insulation resistance requirements for submersible pump cables
When installing submersible pumps, the cables should be overhead and the power cord should not be too long. When launching or lifting a submersible pump, do not force the cable to avoid breaking the power cord. When the submersible pump is working, do not sink into the mud, otherwise it may cause poor heat dissipation of the motor and burn out the motor winding. During installation, the insulation resistance of the motor should not be less than 0.5 megohms.
Avoid frequent switching
Do not frequently switch on and off the submersible pump, as it will generate backflow when the electric pump stops. If started immediately, the motor load will start, causing excessive starting current and the winding to be burned out. Due to the high current during startup, frequent startup can also burn out the motor winding of the submersible pump.
Install leakage protector
Leakage protector, also known as life protector, its function can be understood from the three words' life protector '. Submersible pumps operate underwater and are prone to leakage, resulting in power loss and even electric shock accidents. If a leakage protector is installed, as long as the leakage value of the submersible pump exceeds the operating current value of the leakage protector (generally not exceeding 30 milliamperes), the leakage protector will cut off the power supply of the submersible pump to ensure safety and avoid leakage and energy waste.
Prohibit long-term overloading of submersible pumps
To avoid long-term overload operation of submersible pumps, do not pump water with high sand content at any time, and observe whether the current value on the nameplate is specified. If excessive current is found, the inspection should be stopped. In addition, the dehydration time of the electric pump should not be too long to avoid overheating and burning of the motor.
Pay attention to daily maintenance
Check the motor, if there are cracks on the lower cover, damage or malfunction of the rubber sealing ring, it should be replaced or repaired in a timely manner to prevent water from seeping into the machine.
Try to avoid low voltage starting as much as possible
The power supply voltage shall not differ by 10% from the rated voltage. Excessive voltage can cause the motor to overheat and burn out the windings. If the voltage is too low, the motor speed will decrease. If the rated speed cannot be reached by 70%, the starting centrifugal switch will be closed, resulting in prolonged electrification, heating, and even burning of the winding and capacitor during the starting winding. Do not frequently switch on and off the motor, as there will be backflow when the electric pump stops. If started immediately, the motor load will start, causing excessive starting current and the winding to burn out.