Safety Protection Method Of Submersible Pump

Sep 02, 2022

Submersible pumps are important equipment for deep well water extraction. When in use, the whole unit dives into the water to work, extracting groundwater to the surface, which is used for domestic water, mine rescue, industrial cooling, farmland irrigation, seawater lifting, ship load regulation, and can also be used for fountain landscapes. Hot water submersible pumps are used for hot spring bathing, and can also be used to extract groundwater from deep wells, and can also be used in water extraction projects such as rivers, reservoirs, and canals. It is mainly used for farmland irrigation and water for people and animals in high mountain areas. It can also be used for central air-conditioning cooling, heat pump units, cold pump units, cities, factories, railways, mines, and construction site drainage. The general flow can reach 5~650m3/h, and the lift can reach 10-550 meters. Submersible pumps often burn out motor windings due to lack of water in the pool. In response to this situation, today we have sorted out several protection measures for submersible pumps: water shortage protection, motor water leakage protection, oil room water leakage protection, insulation resistance protection, winding overheating protection, bearing overheating protection, etc.

Submersible pumps are important equipment for deep well water extraction. When in use, the whole unit dives into the water to work, extracting groundwater to the surface, which is used for domestic water, mine rescue, industrial cooling, farmland irrigation, seawater lifting, ship load regulation, and can also be used for fountain landscapes. Hot water submersible pumps are used for hot spring bathing, and can also be used to extract groundwater from deep wells, and can also be used in water extraction projects such as rivers, reservoirs, and canals. It is mainly used for farmland irrigation and water for people and animals in high mountain areas. It can also be used for central air-conditioning cooling, heat pump units, cold pump units, cities, factories, railways, mines, and construction site drainage. The general flow can reach 5~650m3/h, and the lift can reach 10-550 meters. Submersible pumps often burn out motor windings due to lack of water in the pool. In response to this situation, today we have sorted out several protection measures for submersible pumps: water shortage protection, motor water leakage protection, oil room water leakage protection, insulation resistance protection, winding overheating protection, bearing overheating protection, etc.

Safety protection method of submersible pump

1. It is forbidden to start the machine with abnormal power supply voltage

Because the low-voltage power supply line is relatively long, it is common for the voltage at the end 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 motor speed of the submersible pump will drop. 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 heat up or even burn out. windings and capacitors. On the contrary, the high 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 rotation direction of the motor should be clarified. Now there are many types of high-lift submersible pumps that can discharge water in both forward and reverse rotations, but the water output is small and the current is large during 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 pump, the cable should be overhead, and the power cable should not be too long. Do not apply force to the cable when the submersible pump is launched or lifted, so as not to cause the power cord to break. Do not sink into the mud when the submersible pump is working, otherwise it will cause poor heat dissipation of the motor and burn the motor windings. During installation, the insulation resistance of the motor should not be lower than 0.5 megohms.

4. Avoid frequent switching

Do not switch on and off the submersible pump frequently, this is because backflow will occur when the electric pump stops, and if it is turned on immediately, the motor load will start, resulting in excessive starting current and burning out the windings. Due to the large current at startup, frequent startup will also burn out the submersible pump motor windings.

5. Installation of leakage protector

The leakage protector is also called a life saver, and its function can be understood from the three words of life saver. Because the submersible pump works underwater, it is easy to leak electricity, 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 no more than 30 mA), the leakage protector will cut off the power supply of the submersible pump to ensure safety and avoid leakage and waste of electricity.

6. Prohibit long-term overloading of submersible pumps

In order to avoid the long-term overloading of the submersible pump, do not pump water with high sand content and observe whether the current value is in the value specified on the nameplate at any time. If the current is found to be too large, it should be stopped for inspection. In addition, the dehydration time of the electric pump should not be too long, so as not to overheat the motor and burn it.

7. Pay attention to daily maintenance

Usually, check the motor more often. If the lower cover is found to be cracked, the rubber sealing ring is damaged or invalid, etc., it should be replaced or repaired in time to prevent water from infiltrating the machine.

8. Try to avoid booting at low voltage

The difference between the power supply voltage and the rated voltage should not be 10%. If the voltage is too high, the motor will overheat and the winding will be burned. If the voltage is too low, the motor speed will drop. It will heat up and even burn out the windings and capacitors after being energized for a long time. Shanghai speed pump valve reminder: Do not switch the motor frequently, this is because the backflow will occur when the electric pump stops, and if it is turned on immediately, the motor load will start, resulting in excessive starting current and burning out the windings.