Fault phenomenon

Root cause analysis

Exclusion method

No water comes out after startup

(1) Impeller stuck

(2) The power supply voltage is too low

(3) Power outage or phase failure

(4) Cable breakage

(5) Damaged plug

(6) The voltage drop of the cable is too high

(7) The stator winding is damaged; Serious imbalance of resistance; One or both phases are broken; The insulation resistance to ground is zero

(1) Remove debris and manually rotate the impeller to see if it can rotate. If the end face of the impeller is found to be rubbing against the mouth ring, a gasket must be used to elevate the impeller slightly

(2) Switch to high head water pumps or reduce the head of electric pumps

(3) Step by step check the fuse and switch parts of the power supply, identify and eliminate faults; Check if the contacts of the three-phase temperature relay are connected and make them work properly

(4) Identify the breakpoint and connect the cable properly

(5) Replace or repair the plug

(6) Select the appropriate cable specifications based on the length of the cable, increase the conductive area of the cable, and reduce the voltage drop of the cable

(7) Overhaul the stator winding by rewinding it according to the original design data

Insufficient water output

(1) Head too high

(2) Filter blockage

(3) Blockage in the impeller flow section

(4) The impeller is not turning correctly

(5) Wear of impeller or mouth ring

(6) The diving depth of the submersible pump is not sufficient

(7) The power supply voltage is too low

(1) Choose the pump model or reduce the head height according to the actual required head height

(2) Remove water plants and other debris around the grille of the submersible pump

(3) Disassemble the pump part of the submersible pump and remove debris

(4) Connect any two non grounding wires of the power cord for replacement

(5) Replace the impeller or mouth ring

(6) Deepen the diving depth of the submersible pump

(7) Reduce head

Fault phenomenon

Root cause analysis

Exclusion method

The electric pump suddenly stops running

(1) Protection switch trips or fuse burns out

(2) Power outage or phase failure

(3) The outlet box of the submersible pump is filled with water, and the connecting wire is burnt out

(4) Stator winding burnt out

(1) Identify the specific cause of the tripping of the protective switch or the burning of the fuse, and then prescribe the right medicine to adjust and eliminate it

(2) Connect the wires

(3) Open the wire box, connect the broken wire package with insulation tape, eliminate the cause of water leakage in the outlet box, and assemble it as it is

(4) Re offline the stator winding for major repairs. In addition to timely replacement or maintenance of the stator winding, the root cause of the fault should also be identified and eliminated based on the specific situation

Stator winding burnt out

(1) The grounding wire is incorrectly connected to the power cord

(2) When working with a broken phase, the current is much higher than the rated value, and the temperature rise of the winding is very high. Over time, it can cause insulation aging and damage to the stator winding

(3) Mechanical seal damage leads to water leakage, reducing the insulation resistance of the stator winding and damaging the winding

(4) The impeller is stuck, and the turtle pump is in a three-phase braking state. At this time, the current is about six times the rated current. If there is no switch protection, the winding will quickly burn out

(5) The end of the stator winding collides with the casing of the submersible water pump, resulting in ground breakdown

(6) The submersible pump starts and stops too frequently

(7) The dehydration operation time of the submersible pump is too long

(1) Correctly connect the grounding wire in the submersible pump cable to the grounding wire or temporary grounding wire of the power grid

(2) Promptly identify the cause, connect the disconnected power cord, or replace the cable

(3) Regularly check the insulation resistance of the submersible electric pump, and take timely measures to repair it when the insulation resistance decreases

(4) Take measures to prevent debris from entering the submersible pump and getting stuck in the impeller. Pay attention to checking the mechanical damage of the submersible pump to avoid the impeller getting stuck due to some kind of mechanical damage. At the same time, if the water pump suddenly stops flowing during operation, it should be shut down immediately for inspection and corresponding measures should be taken for maintenance

(5) When re embedding the winding, try to handle the two ends as well as remove the iron lumps on the inner surfaces of the upper and lower covers. During assembly, avoid the winding ends from touching the outer shell

(6) Do not turn on or off the electric pump too frequently to avoid overloading or unnecessary impact loads on the submersible pump. If it is necessary to restart the submersible pump, wait for the water in the pipeline to return before restarting

(7) During operation, close attention should be paid to the decrease in water level, and the electric pump should not be operated in the air for a long time (more than 1 minute) to avoid the submersible pump lacking heat dissipation and lubrication conditions