Common Problems and Solutions to Three Phase Submersible Automatic Starter

Three-phase submersible automatic starters are used to control and protect submersible pumps in agricultural and industrial applications. Here are some common issues with these starters and solutions to resolve them:

1. Starter Fails to Start the Pump

• Cause: Phase imbalance, blown fuse, or power supply issues.
• Solution:
  • Check if all three phases are correctly balanced. An imbalance may indicate a faulty transformer or poor power supply.
  • Inspect fuses for each phase. Replace any blown fuses.
  • Ensure all connections are tight and no wires are loose. Confirm the voltage matches the starter’s requirements.

2. Frequent Tripping of Starter

• Cause: Overload, phase loss, or high current.
• Solution:
  • Verify that the pump motor’s load is within the starter’s rated capacity. If the load is too high, consider reducing the pump load or upgrading the starter.
  • Check for phase loss using a phase-loss detector or multimeter. If one phase is missing, troubleshoot the power supply to restore it.
  • Test the current drawn by the motor. If it’s consistently high, it may indicate a motor fault, wiring issue, or problem with the pump.

3. Overheating of Starter or Pump Motor

• Cause: Insufficient cooling, high ambient temperature, or overloaded motor.
• Solution:
  • Ensure the starter is installed in a ventilated area to dissipate heat effectively.
  • Confirm that the pump’s motor is not drawing excessive current, which may be due to an overload.
  • Check if the thermal overload relay is set correctly to the motor’s full load current. Adjust if necessary to prevent overheating.

4. Motor Runs in Reverse

• Cause: Incorrect phase sequence.
• Solution:
  • Swap any two of the three phases to correct the rotation. Re-check the direction of the motor.
  • Test the phase sequence to ensure consistent proper rotation, as incorrect rotation can damage the pump.

5. Frequent Short Circuiting

• Cause: Water ingress, insulation failure, or wiring fault.
• Solution:
  • Inspect the starter casing and all connectors to ensure no water can enter. Use waterproofing as needed.
  • Test insulation resistance using a megger. Replace any damaged cables with new, properly insulated cables.
  • Examine and replace any worn or damaged wiring.

6. Starter Makes Clicking or Humming Sounds

• Cause: Faulty contactor, relay, or capacitor (in some setups).
• Solution:
  • Check the contactor for wear or dirt buildup. Clean or replace the contactor if necessary.
  • Inspect the relay for faults. Replace if it’s worn out or not functioning properly.
  • If a capacitor is used, test it with a multimeter and replace if weak or defective.

7. Phase Failure or Phase Imbalance Issues

• Cause: Faulty supply line or uneven phase distribution.
• Solution:
  • Test each phase for consistent voltage and troubleshoot the supply lines if there are issues.
  • Install a phase failure relay to automatically shut down the pump in the event of a phase failure, preventing motor damage.

8. Pump Runs but No Water Discharge

• Cause: Motor running in reverse, clogged intake, or airlock.
• Solution:
  • Confirm the motor’s rotation direction. If incorrect, switch any two phases to reverse it.
  • Check the intake for debris or blockages and clean if necessary.
  • Ensure the pump is properly primed to prevent airlock issues.

9. Indicator Lights Malfunctioning

• Cause: Faulty LED indicators, loose wiring, or phase loss.
• Solution:
  • Inspect and replace any damaged LED indicators.
  • Tighten any loose wiring or connections within the indicator circuit.
  • Check each phase for continuity and voltage; address any inconsistencies to restore proper indicator function.

10. Burning Smell or Visible Sparks

• Cause: Overloading, overheating, or internal component failure.
• Solution:
  • Immediately shut off power to prevent further damage.
  • Inspect the internal components, such as relays and contactors, for signs of burning or melting. Replace as necessary.
  • Verify that the starter’s rating matches the pump’s requirements to prevent overloading.

11. Motor Stalls or Loses Power Mid-Operation

• Cause: Voltage drop, loose wiring, or capacitor failure.
• Solution:
  • Check if the voltage remains stable and within the motor’s operating range. A voltage stabilizer may be necessary if voltage fluctuations are frequent.
  • Tighten all wiring connections to prevent power loss due to loose contacts.
  • Replace any faulty capacitors if applicable, especially in setups with starting capacitors.

12. Automatic Mode Not Working (Manual Works Fine)

• Cause: Faulty automatic control system, timer, or level sensor issues.
• Solution:
  • Inspect and reset the automatic timer or controller if necessary. Replace if it fails to engage.
  • Test the level sensors or float switches for continuity. Replace faulty sensors to restore automatic operation.
  • Check the wiring between the sensors and the controller for loose or broken connections.

Regular Maintenance Tips

• Routine Testing: Regularly test the voltage and current levels to ensure the system is running smoothly.
• Clean Contactors: Dust and dirt buildup can cause poor contact. Clean or replace contactors periodically.
• Tighten Connections: Periodically check for and tighten loose wires, as vibration can cause connectors to loosen over time.
• Test and Adjust Relays: Ensure overload relays are set to the correct ratings and replace if worn out.

By following these solutions and maintenance tips, you can ensure that a three-phase submersible automatic starter functions reliably, safeguarding both the pump and the irrigation system from frequent breakdowns and costly repairs.