Proper Use Of Sewage Submersible Pumps Can Prolong Their Service Life

Dec 26, 2025

In sewage treatment, the use of pumps is very frequent. So how can we make our submersible sewage pumps better and last longer?

1. Determine the correct direction of rotation for the motor

The rotation direction of the motor should be clarified. Nowadays, there are many types of sewage submersible pumps that can produce water when rotating in both forward and reverse directions. However, the water output is small and the current is high when rotating, which can damage the motor winding if the rotation time is too long.

2. Prevent abnormal power supply voltage during startup

Because low-voltage power supply lines are relatively long, it is common for the terminal voltage of the line to be too low. When the phase voltage is lower than 198 volts and the line voltage is lower than 342 volts, the speed of the sewage submersible pump motor decreases. When it does not reach 70% of the additional speed, the centrifugal switch will close, causing the starter winding to be continuously energized and generate heat, even burning out the winding and capacitor. On the contrary, excessive voltage causes the motor to overheat and burn out the windings. Therefore, during the operation of the sewage submersible pump, it is necessary for the operator to investigate the power supply voltage value at any time. If it is below 10% of the additional voltage and above 10% of the additional voltage, the motor should be stopped, the cause should be identified, and the fault should be eliminated.

 

3. Insulation resistance requirements for cable devices and sewage submersible pumps

When installing a submersible sewage pump, the cable should be overhead and the power line should not be too long. Do not put force on the cable when diving or lifting the sewage submersible pump to prevent the power line from cracking. Do not sink the submersible pump into the mud during operation, otherwise it may cause poor heat dissipation of the motor and burn out the motor winding. When installing, the insulation resistance of the motor should not be less than 0.5 megohms.

4. Device for residual current maintenance equipment

The leakage protector, also known as the life protector, can be understood from the three words' life protector 'for its effectiveness. Because sewage submersible pumps operate underwater, simple electrical leakage can cause loss of electrical energy and even lead to electric shock incidents. If equipped with a leakage protector, as long as the leakage value of the sewage submersible pump exceeds the operating current value of the leakage protector (usually not exceeding 30mA), the leakage protector will block the power supply of the submersible pump to ensure safety and prevent leakage and damage to electrical energy.

5. Prevent frequent switching

Do not frequently turn on and off the submersible pump, as backflow may occur when the electric pump stops. If you turn it on immediately, it will cause the motor load to start, resulting in excessive starting current and burning out the winding. Because the current is high when starting, frequent starting can also burn out the motor winding of the sewage submersible pump.

6. Do not allow sewage submersible pumps to operate at overload for a long time

To prevent the submersible electric pump from operating under overload for a long time, do not pump water with high sediment content and constantly investigate whether the current value is the regular value on the nameplate. If the current is found to be too high, stop the machine and check. Additionally, the dehydration operation time of the electric pump should not be too long to prevent the motor from overheating and burning out.

7. Pay attention to regular maintenance

It is necessary to regularly check the motor. If cracks are found on the lower cover, damaged or ineffective rubber sealing rings, etc., they should be replaced or corrected in a timely manner to prevent water from entering the submersible pump.
Pay attention to the use of sewage submersible pump maintainers and pay attention to some routine maintenance, which can greatly extend the service life of submersible pumps.