Troubleshooting - DAB GRINDER Serie Istrucciones De Servicio

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Electric submersible pumps for sewage

11. TROUBLESHOOTING

GB
INCONVENIENTS
Failure in
electric pump
Electric pump starting with
thermal protection
intervention winding.
Electric pump drawing
more power than
value of plate
Insufficient performances
38
Use and maintenance instructions
PROBABE CAUSES
1. Lack of current to the motor.
Insufficient voltage.
2.
Thermal protection activated.
3.
a) single-phase motor
b) three-phase motor
Defective non operating floating switch.
4.
5. No signal from electrodes for level control.
Single-phase motor: defective condenser.
6.
Motor failure.
7.
One phase interruption (three-phase
8.
motors) .
Clogged impeller.
9.
10. Voltage different from plate.
Three-phase motor: phase interruption.
11.
Three-phase motor: Low rating.
12.
13. Short-circuit; earth leakage in electric
cables or motor.
Too high temperature of pumped liquid.
14.
15. Pumped liquid too dense.
Dry running of the electric.
16.
Defective thermal relay.
17.
Overload due to pump clogged .
18.
Pumped liquid too dense or viscious .
19.
20. Overload due to obstruction.
21. Damaged motor bearings.
22. Wrong rotation direction.
23. Insufficient pressure required .
24. Suction, impeller, valve ordelivery pipeline clogged.
25. Weared pump or impeller.
26. Air or gas in the pumped liquid.
REMEDIES
1. Check electric network, supply cables, connections
and fuses.
2. Verify value (see par. 3.4 :Use limits).
3. a) Wait for motor cooling (see par."electric
connections").
b) Reset thermal relay and check ratin starting.
4. Clean and check efficiency; (contact the Assistance
Service if necessary).
5. Wait for level reset, check efficiency of level control
relay and relevant electrodes.
6. Check and eventually replace condenser.
7. Contact the Assistance Service.
8. Reset connections.
9. Remove obstruction, wash and clean ( contact the
Assistance Service if necessary).
10. Check the power supply voltage value.
11. Reset connections.
12. Adjust rating of relay value.
13. Individuate interruption and repair (contact the
Assistance Service if necessary).
14. Check whether the right type of pump has been
selected.
15. Dilute liquid. Check whether the right type of pump
has been selected.
16. Verify liquid level and level pump.
17. Replace it.
18. Remove obstruction and clean (contact Assistance
Service if necessary).
19. Dilute liquid. Check whether the right pump has
been selected.
20. Remove obstruction and clean of extraneous
bodies.
21. Replace. Contact the Assistance Service.
22. Invert two of the three phases.
23. Increase electric pump pressureby the installation .
reducing flow.Check whether the right pump has
been selected.
24. Clean carefully.
25. Replace or repair.
26. Increase dimensions of pit or collecting tank and
foresee degasing devices.