Submersible sewage pump will burn out the motor windings due to lack of water in the pool. In response to this situation, today we have organized several protection measures for Submersible sewage pump: water shortage protection, motor water leakage protection, oil chamber water leakage protection, insulation resistance protection, winding overheating protection, bearing overheating protection, etc.

 Submersible sewage pump correct and safe protection
1. It is forbidden to turn on abnormal power supply voltage
Because the low-voltage power supply line is relatively long, the end voltage of the line is often too low. When the phase voltage is lower than 198 volts and the line voltage is lower than 342 volts, the motor speed of the Submersible sewage pump will decrease. When it does not reach 70% of the rated speed, the start centrifugal switch will be closed, causing the start winding to be energized for a long time and cause heat or even burn. Bad windings and capacitors. On the contrary, excessive voltage causes the motor to overheat and burn out the windings. Therefore, during the operation of the submersible pump, the operator must observe the power supply voltage value at any time. If it is less than 10% of the rated voltage and more than 10% of the rated voltage, the motor should be stopped to find out the cause and eliminate the fault.
2. Confirm the correct rotation direction of the motor
The direction of rotation of the motor should be clarified. There are many types of Submersible sewage pumps that can discharge water in both forward and reverse rotations. However, the water output is small and the current is large in reverse rotation. The long reverse rotation time will damage the motor windings.
3. Cable installation and insulation resistance requirements of submersible pumps
When installing the Submersible sewage pump, the cable should be overhead and the power cable should not be too long. When the submersible pump is launched into the water or raised, do not apply force to the cable, so as not to cause the power cord to break. Do not sink into the mud when the Submersible sewage pump is working, otherwise it will cause poor heat dissipation of the motor and burn out the motor windings. During installation, the insulation resistance of the motor should not be less than 0.5 megohm.
4. Avoid frequent switching
Do not switch the submersible pump frequently. This is because the electric pump will produce backflow when it stops. If it is turned on immediately, the motor load will start, resulting in excessive starting current and burning of the windings. Due to the large current when starting, frequent starting will burn out the windings of the submersible pump motor.
5. Installation of leakage protector
Leakage protector is also called life protector, and its function can be understood from the three words life protector. Because the Submersible sewage pump works underwater, it is easy to leak electricity and cause power loss and even cause 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 no more than 30 mA), the leakage protector will cut off the power supply of the submersible pump to ensure safety, while avoiding leakage and wasting electric energy.
6. Prohibit long-term overload work of submersible pumps
In order to avoid long-term overloading of Submersible sewage pump, do not pump water with high sand content and observe whether the current value is at the value specified on the nameplate at any time. If the current is too large, it should be shut down for inspection. In addition, the dehydration operation time of the electric pump should not be too long, so as to avoid the motor overheating and burning.
7. Pay attention to daily maintenance
Check the motor frequently. If you find cracks in the lower cover, damage or failure of the rubber seal ring, etc., you should replace or repair it in time to prevent water penetration into the machine.
8. Try to avoid starting at low pressure
The power supply voltage and the rated voltage should not differ by 10%. Excessive voltage will cause the motor to overheat and burn out the windings. If the voltage is too low, the motor speed will decrease. If it does not reach 70% of the rated speed, the start centrifugal switch will be closed, causing the winding to start. Long time energization will heat up and even burn out windings and capacitors. Do not switch the motor frequently. This is because when the electric pump stops rotating, there will be backflow. If it is turned on immediately, the motor load will start, resulting in excessive starting current and burning of the windings.