small submersible pump is necessary for farm irrigation and water for life for it is small and light. In order to avoid accidents in the operation process, extend service life and play its good performance, the following seven points should be noticed at operation:
1. Installation of leakage protector
2. small submersible pump is easy to leakage for it works under the water, which may cause energy loss or even electric shock. If leakage protector is installed, it will shut off the electricity of submersible pump once the leakage value exceeds action current value of the leakage protector (no more than 30mA) to avoid waste of electric energy and ensure safety.
2. Do not operate the pump with abnormal power supply voltage
For long low-pressure power supply circuit in rural areas, it is general that voltage is too low at the end of the circuit. When phase voltage is lower than 198 volts and line voltage lower than 342 volts, motor speed of submersible pump will decrease; when it cannot reach 70% of rated speed, centrifugal switch will be closed, which will lead to starting winding be energized for a long time and burn winding and capacitor. On the contrary, higher voltage will lead to motor overheating and burn winding. Thus, operators must notice the value of power supply voltage at any time in the operation process. If the value is lower than 10% of rated voltage and higher than 10% of rated voltage, the motor should be stopped to seek the reason and remove the trouble.
3. Avoid starting and closing the pump frequently
Do not start and close the submersible pump frequently, for back flow will be occurred when the pump is stopped to operation. If start it immediately, the motor will be started with load, which will lead to a large starting current and burn winding. Frequent start will also burn motor winding of the submersible for the voltage is too large when start the pump.
4. Avoid long-term overload operation of small submersible pump
In order to avoid long-term overload operation of submersible pump, do not pump water containing much sand and notice if the current value is in the scope specified on the nameplate at any time; if find the current is too large, the pump should be stopped to make a inspection. In addition, dehydration running time of the pump should not be so long to avoid motor overheating and burning.
5. Rotation direction of the motor should be correct
Rotation direction of the motor should be cleared. Currently, there are many types of submersible pumps that are capable of delivering water both forward and reverse. However, water volume is small and current is large when reverse and for a long time it will damage the motor winding.
6. Requirements of cable installation and insulation resistance of submersible pump
When install the submersible pump, cable should be overhead and power cord should not be so long. Do not force the cable when the submersible pump is put into or put forward the water to avoid power cord fault. Submersible pump should not be sank into the mud at operation, or it will lead to poor heat dissipation of the motor and burn motor winding. At installation, insulation resistance of motor should be no less than 0.5 ohms.
7. Repair timely if find problems
Always check the motor at ordinary time. If find cracked lower cover, damaged or failed rubber seal ring, etc, should replace or repair them timely to avoid water infiltration small submersible pump.
