1, Technical inspection before work
1. Line inspection: The discharge circuit of the submersible pump valve should be complete, connected correctly and reliably, and equipped with overcurrent protection devices. If a knife switch is used, a qualified fuse must be used. Do not thicken or replace it with other wires at will. The cable connection should be accurate to prevent the power line from being connected to the motor neutral wire incorrectly. The connection between the motor lead and the cable should be reliable, otherwise it will heat up due to poor contact, causing short circuits or open circuits.
2. Grounding wire: Grounding wires that meet technical standards should be used.
After soaking the cable in water for 22 hours, use a 500V or 1000V megohmmeter to check the insulation of the motor winding to ground, and the resistance value should not be less than 5 megohmmeters.
4. Some submersible pumps can produce water in both forward and reverse directions, but the reverse direction produces less water and increases the current, which is not conducive to the motor winding. Therefore, before starting the unit, the motor should be filled with pure water (wet submersible pump), and the pump should be filled with water to lubricate the bearings. Then, connect the power and start the motor instantly. Observe the direction of rotation of the motor, and only confirm that there are no abnormalities in the direction of rotation can the unit be officially started.
5. Keep the pump unit in the correct position underwater. The pump should be kept upright in the water, not tilted, and securely fixed, especially not buried in soil to prevent the electric pump from burning out. The diving depth should be kept 1-2 meters below the water surface and not less than 3 meters from the bottom of the well to facilitate the suction of clean water.
2, Precautions after startup
The correct use of the starter motor during operation should first close the gate, wait for normal operation, then slowly open it and adjust it to the required flow rate. At the same time, observe whether the pressure gauge and ammeter are correct. The disk assembly should have no vibration or abnormal noise. If any of the above items are abnormal, work should be carried out after troubleshooting.
1. Always observe the instrument. When the voltage is below 340 volts and the current is greater than 20% of the rated current of the motor, the machine should be stopped immediately for maintenance.
2. Regularly check the insulation. During operation, regularly check the insulation resistance of the motor to ground in a hot state. If the resistance value is below 0.5 megaohms, immediately stop the machine for maintenance. This insulation inspection should be conducted once a week to ensure safety.
3. Requirements for well water and well water: The sand content in well water should be less than 0.2%, otherwise it will damage the seal of the pump unit. The well diameter and depth should be compatible with the model of the pump unit.
4. The pump unit should not be started and stopped frequently. When restarting the pump unit after shutdown, wait for the water in the pipeline to swallow before starting, usually with an interval of about 5 minutes. Otherwise, starting with load will increase the current too much and damage the motor.
To prevent electric leakage from injuring people, during the operation of the pump, in order to avoid leakage and personal injury, in addition to the leakage protection device, personnel are strictly prohibited from contacting the water source near the pump outlet.
