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The Fengqiu submersible pump operates underwater. Taking the Fengqiu submersible pump as an example, it has a compact design and low weight, and does not require a long drive shaft when pumping water from a well. Therefore, submersible pumps are very suitable for rural well water irrigation. The JQB type submersible pump is the most commonly used. This submersible pump uses waterproof measures such as mechanical seals or air seals to keep the interior of the motor dry and prevent water from entering. When using it, pay attention to the following points: (1) Check whether the seals at the pump’s air release hole, water release hole, oil release hole, and cable connections are loose; if they are loose, tighten them. (2) Use a 500-volt megohmmeter to check the insulation resistance, which should be no less than 0.5 megohms. If it is lower than this value, open the water and air release ports, and carry out drying or sun-drying. (3) Inspect the cable; if it is damaged or broken, it should be replaced to prevent electric leakage. (4) Before starting, check all the circuits and switches to ensure that the wiring is correct and secure. Then, run the motor at idle in the air for 3–5 minutes (the time should not be too long to avoid damaging the components or burning out the motor windings). Also, check whether the rotation direction of the motor is correct. Only if everything is fine can the motor be used underwater. (5) When using a submersible pump in water, the cable must not be under any stress; it should be tied to a frame at the wellhead using a rope. The maximum depth at which the electric pump can be submerged in water is 3 meters, while the minimum depth is 0.5 meters (measured from the center of the impeller). (6) During operation, the water level in the well should be monitored regularly. The motor must not emerge above the water surface nor get stuck in silt, to prevent damage to its windings due to poor cooling. The electric pump should be raised or lowered as the water level in the well changes. If the water flow decreases or is interrupted, the cause should be identified immediately or the machine should be shut down for inspection. The cable must not rub against the well wall, to prevent well water from seeping into the motor through the cable core in case the cable gets damaged. (7) For submersible pumps with new or replaced integral seal boxes, the seal should be checked after 50 hours of use; thereafter, it should be inspected once a month. At the same time, the seal of the shielding sleeve between the motor rotor and stator should also be checked. (8) After one year of use, the pump should be inspected for rust, and rust removal and repainting should be carried out. If a submersible pump is not used for an extended period, it should be carefully inspected before being stored in a dry and well-ventilated place.