Correct Maintenance Of Submersible Sewage Pump

　　The submersible sewage pump is mainly composed of an impeller, pump body, base, submersible motor, and so on. The transformed sewage pump is mainly used in construction sites, septic tanks, and other environments with sewage and sundries. The water pump and all copper motors are on the same shaft. Since the water pump is located at the lower end of the entire sewage pump, the remaining sewage can be pumped to the largest area. Submersible sewage pumps usually burn out the pump motor due to a lack of water in the suction pool. Therefore, it is necessary to strengthen the water shortage protection, motor water leakage protection, oil chamber water leakage protection, insulation resistance protection, winding overheating protection, and bearing overheating protection for submersible sewage pumps.

　　1 Prohibition of abnormal power supply voltage

　　Due to the long low-voltage power line, it is common for the terminal voltage of the line to be too low. When the phase voltage is lower than 198V and the line voltage is lower than 342V, the motor speed of the submersible pump will decrease. When it does not reach 70% of the rated speed, the starter centrifugal switch is closed, so that the starter winding is energized for a long time, heating or even burning the winding and capacitor. Conversely, too much voltage can cause the motor to overheat, burning out the windings. Therefore, during the operation of the submersible pump, the operator needs to observe the power supply voltage at any time. When it is more than 10% lower than the rated voltage and more than 10% higher than the rated voltage, stop the motor, 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 specified. At present, there are many high-lift sewage pumps, which can basically discharge water during forward rotation and reverse rotation, but when reverse rotation, the water output is small and the current is large. If the reversing time is long, the motor winding will be damaged.

　　3 Cable installation and submersible pump insulation resistance requirements

　　When installing the submersible pump, the cable should be overhead, and the power cord should not be too long. When the submersible pump is started or raised, do not use force to avoid disconnecting the power cord. When the submersible pump is working, do not sink into the mud, otherwise, it will cause poor heat dissipation of the motor and burn out of the motor winding. When installing, the insulation resistance of the motor should not be less than 0.5 megohms.

　　4 Avoid frequent switching

　　Do not turn the submersible pump on and off frequently, as backflow can occur when the electric pump stops running. If it is started immediately, the motor load will start, causing the starting current to be too large and the winding to burn out. Due to the large current during the starting process, frequent starting will also burn the motor windings of the submersible pump.

　　5 Leakage protector installation

　　A leakage protector is also called a life protector. Its function can be understood from the three words of life protector. Since the submersible pump works underwater, it is easy to leak electricity, causing power loss or even electric shock. 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 30mA), the leakage protector will cut off the power supply of the submersible pump to ensure the safety and avoid leakage and waste of electric energy.

　　6 It is forbidden to overload the submersible pump for a long time

　　In order to avoid long-term overload operation of the submersible pump, do not pump water with large sand content, and observe whether the current value is the value specified on the nameplate at any time. If the current is found to be too large, the pump should be stopped for inspection. In addition, the dehydration running time of the electric pump should not be too long, so as to avoid the motor from overheating and burning out.

　　7 Pay attention to daily maintenance

　　Check the motor more often. When the lower cover has cracks or the rubber sealing ring is damaged or fails, it should be replaced or repaired in time to prevent water from seeping into the machine.

　　8 Try to avoid starting under low pressure

　　The difference between the supply voltage and the rated voltage should not be more than ten percent. If the voltage is too high, the motor will overheat and burn the windings. If the voltage is too low, the motor speed will decrease. If it cannot reach 70% of the rated speed, the starting centrifugal switch will be closed, and after the starting winding is energized for a long time, the winding group and capacitor will heat up and even burn out. Do not turn the motor on and off frequently, because turning it on immediately when backflow occurs will load the motor and cause the motor winding to burn out.